There were significant differences by ancestry: HDLc was positively associated with eGFR in HC , but negatively associated among African ancestry populations . These differences were also seen in nationally-representative NHANES data . To further explore the findings in African ancestry populations, we investigated the role of an African ancestry-specific nephropathy risk variant, rs73885319, in the gene encoding HDL-associated APOL1. Among AA, an inverse HDLc-eGFR association was observed only with the risk genotype . This interaction was not seen in WA. In summary, counter to expectation, an inverse HDLc-eGFR association was observed among those of African ancestry. Given the APOL1 × HDLc interaction among AA, genetic factors may contribute to this paradoxical association. Notably, these findings suggest that the unexplained mechanism by which APOL1 affects kidney-disease risk may involve HDLc. Low levels of high-density cholesterol (HDLc) accompany chronic kidney disease, but the association between HDLc and the estimated glomerular filtration rate (eGFR) in the general population is unclear. We investigated the HDLc-eGFR association in nondiabetic Han Chinese (HC,  Dyslipidemia is a known correlate of chronic kidney disease (CKD), with increased triglycerides (TG) and decreased high-density lipoprotein cholesterol (HDLc) consistently observed , 2. The There are consistent reports of an inverse association between TG –14 and, Given the variety of methods used in projects that provide evidence on this relationship, it is difficult to ascertain whether such variability in association is a consequence of real population-level differences, specific kidney function measures considered, or analytical strategies. Therefore, we evaluated the relationship between HDLc and kidney function in different populations purposefully designed to have consistent data and biological specimen collection and analyzed identically.Consideration of diverse populations is especially relevant in describing the HDLc-kidney function association for several reasons. First, the rates of CKD  vary significantly by population and ancestry, for reasons that are unclear. For instance, in the US, African Americans have a nearly 3-fold higher risk of CKD , and botApolipoprotein L1 gene (APOL1) that increase kidney disease risk [APOL1 variant, rs73885319, was also assessed.The recent discovery of missense variants in the ase risk  among Afase risk , has notEthical approval for each study was obtained from the responsible Institutional Review Board (IRB) at each study site/institution, Howard University, and the National Institutes of Health. All subjects provided written informed consent for the collection of samples and subsequent analysis. This study was conducted according to the principles expressed in the Declaration of Helsinki.Participants originated from three separate epidemiological studies: the Africa America Diabetes Mellitus (AADM) Study, the Howard University Family Study (HUFS), and the China America Diabetes Mellitus study (CADM). Further details of AADM  and HUFSn = 19; smoking  status, n = 32; alcohol use, n = 6). After exclusions, 4136 participants were considered in the main analysis. The main findings were also investigated in the nationally-representative National Health and Nutrition Examination Survey (NHANES) for years 2007-2008, and 2003-2004 [There were 4574 non-T2D participants across the three studies. Of these, 381 participants were excluded for missing or extreme serum lipid measurements. Additional exclusions were made for missing covariates . After Serum lipids  were determined enzymatically using methods standardized to in-house and other appropriate reference methods  for TC and TG). HDLc was assayed using homogeneous enzymatic colorimetric assays in all cohorts ; AEROSET C8000, Abbott Diagnostics, China (HC), and Roche/Hitachi Modular P Chemistry Analyzer, Roche Diagnostics, IN, USA (NHANES). LDLc was calculated  .r ~ 0.99: reference, http://www.accessdata.fda.gov/cdrh_docs/pdf7/K073634.pdf). These methods have been standardized against ID/MS and primary reference material (SRM 914).For WA, AA, and NHANES, serum creatinine levels were determined using a Jaffé reaction without deproteinization on either a COBAS Integra 400 analyzer  or a Beckman Synchron Analyzer . In HC, serum creatinine was assayed on AEROSET C8000  using an enzymatic reaction. Methods comparison conducted by the manufacturers shows that the two methods yielded acceptable correlation (apolipoprotein L1 (APOL1) risk variant (rs73885319) in 1296 African Americans (HUFS) and 1095 West Africans (AADM). Genotyping was performed using the iPLEX Gold assay on the MassArray platform  as previously described [P > 0.05) and concordance of duplicate genotypes was >99.9%.To further evaluate results, we genotyped a major kidney disease t rs738859 in 1296We used as a measure of renal function the estimated glomerular filtration rate (eGFR), which was calculated according to race- and gender-specific Chronic Kidney Disease Collaboration equations . Variabl2, sex, BMI, smoking, LDLc and TG , and alcohol use. For those studies with related participants (HUFS and AADM), an adjustment for the random effect of family was included. To formally evaluate differences in the association between HDLc and eGFR by population, all studies were included in the same model with an HDLc × study interaction term.Given multicollinearity between serum lipid measures and between these and BMI, these variables were mean-centered and normalized. No multicollinearity was observed among the transformed variables. The relationship between eGFR and predictors was analyzed using population-stratified linear regression models adjusted for age, ageAPOL1 rs73885319 was coded recessively . The associations of genotype with HDLc and with eGFR were determined in linear mixed models adjusted for age, age2, and sex, with random clustering for family. For African Americans, principal component analysis to assess population structure was conducted using EIGENSOFT [APOL1 variant and HDLc, an rs73885319 x HDLc product term was added. All analyses were conducted using SAS 9.2 . Data was represented graphically using R (http://www.r-project.org/).Consistent with published findings , APOL1 rIGENSOFT , and theIGENSOFT  ), and iP < 0.0001 versus HC; P = 0.0006 versus AA). Notable differences in serum lipids between the populations were observed. Total cholesterol was much lower among WA than among AA or HC (P < 0.0001), reflecting a lower mean HDLc (P < 0.0001). Triglycerides were highly variable among the three studies, with WA having 15 mg/dl lower mean concentration than AA and nearly 50 mg/dl lower mean concentrations than HC . Lower mean TG levels have been consistently observed in African- compared to European- or Asian-ancestry populations [A total of 4,316 participants met the criteria for inclusion : 1,497 Aulations –42.β−0.19, P < 0.0001) for and AA  and positive association among HC .The association between HDLc and eGFR differed between studies . Most noP < 0.0001). This remained true when only two studies were considered at a time (WA versus AA (P = 0.001), WA versus HC (P < 0.0001), and AA versus HC (P < 0.0001)).As expected, when all studies were included in a single model, an HDLc × study interaction term was highly statistically significant  and negatively associated with eGFR among NHAA .To determine the generalizability of the HDLc findings, analyses were run in European Americans and African Americans from NHANES . These findings supported the results found in the original analysis: HDLc was positively associated with eGFR among NHEA  was 0.21 and 0.38 in AA and WA, respectively.Padjusted = 0.08). A formal test for a gender × rs73885319 interaction was not statistically significant (P = 0.13). There was no evidence of a difference by gender for either trait among the WA.There was no evidence of an association between the variant and eGFR in either population . Althougβ: −0.38 versus 0.001, Pinteraction = 0.03; Pinteraction = 0.4).Among AA participants, a statistically significant interaction between the variant and HDLc was observed: the inverse association between HDLc and eGFR was larger among those with the risk genotype compared to those without  a sensitivity analysis was conducted excluding those with eGFR < 60 mL/min/1.73 mmate GFR  with onlmate GFR . When wemate GFR  for HC amate GFR ), the HDmate GFR . Lipid-lP-value was increased (P = 0.4). The consistent effect size and diminished statistical significance suggest that this difference is due to a reduction in sample size and not bias, a conclusion further supported by the similar results obtained in rerunning analyses in similarly-sized random subsets of the related dataset. As such, there is no evidence from which to infer bias based on the inclusion of related individuals in two of the samples evaluated.Although the HDL-eGFR results from the NHANES AA, which did not include relatives, were consistent with what was observed among WA and HUFS AA, which did include relatives, we conducted a sensitivity analysis to investigate the possibility that the adjustment for relatedness in our models was insufficient to remove a potential bias. When only unrelated participants were included, the association between HDL and eGFR was similar and remained statistically significant. When the analysis of the rs73885319 interaction in HUFS was limited to unrelated participants, the effect size was similar, though the Additionally, no change in the observed results was found with adjustment for hypertension, hypertension treatment, or CRP (CRP not available in AADM or CADM). The use of categorical serum lipid variables did not provide additional insights, though the results were consistent with those observed in the analysis with continuous variables. No consistent patterns of association were observed when the analyses were repeated within strata of serum lipids to further describe the relationships.To address potential concern that ethnicity-specific bias in the eGFR estimating equations could have resulted in an apparently different association by ancestry, we redid the analysis using serum creatinine as the outcome. The results were consistent with the reported observations (an inverse HDLc-eGFR association in non-African ancestry groups and a positive association in the African ancestry groups). APOL1 gene, which encodes an HDL-associated apolipoprotein, was investigated among AA. Among AA women, higher HDLc was observed among those with the nephropathy-associated genotype. Further, among African American men and women, the inverse association between HDLc and eGFR was only observed in those with the risk genotype.In this investigation of West African (WA), African American (AA), and Han Chinese (HC) adults, the association between kidney function and HDLc varied dramatically by ancestry: a positive association was observed among HC, and an inverse association was found among the two African-ancestry populations. A known nephropathy-associated variant (rs73885319) in the P = 0.2). Similarly, when all three populations were considered together, there was an inverse HDLc-eGFR association (P < 0.0001), despite the strong, statistically significant positive association observed in the HC alone. Without evaluating the interaction term, these data would have led us to conclude that either there was no association of HDLc and eGFR (HC and AA) or that the association could be described as a strong, inverse association between HDLc and eGFR , conclusions that are not appropriate given our analysis.The inconsistency in the direction of the HDLc-eGFR association in WA and AA compared to HC is an important contribution to the current conflicting literature. This variation, found in data that was consistently collected and identically analyzed for three separate epidemiological studies, suggests that the relationship varies at the population level. In support of these findings, a positive association was found in a nationally representative sample of European Americans (NHEA), while an inverse association was observed in a similar nationally representative sample of African Americans (NHAA). In agreement with our findings in non-African ancestry populations, low HDL was associated with increased incidence of CKD among Japanese  and withWhile a positive association of HDLc and eGFR seen in non-African ancestry groups is consistent with the expectation that higher HDLc is associated with a variety of favorable health outcomes, the inverse association observed among WA and two AA populations was not expected. One possibility is that genetically determined characteristics of the HDL particle or its associated proteins differ in those of African versus non-African ancestry in ways that would not be detectable in comparisons of HDLc concentration. For instance, variation may exist in the antioxidant or anti-inflammatory properties of HDL or in the size distribution of its particles in a way that is relevant for kidney function. It has been reported that those of African ancestry typically have a more favorable size distribution of lipid particles than those of non-African ancestry –47. AlthAnother possibility is that HDLc has only an indirect relationship with kidney function, but rather is a biomarker of other genetically-determined traits that are more proximally associated with kidney function, and that this trait (or the relationship between this trait and HDLc) differs dramatically by ancestry. Further support for this hypothesis comes from a recent discovery related to HDLc and risk of myocardial infarction (MI), a relevant disease model given that glomerular and vascular cells have been shown to respond similarly to dyslipidemia . AlthougAPOL1 variants, including rs73885319, are thought to have risen to high frequency in African ancestry populations in areas of endemic trypanosomiasis, as these variants confer protection against a deadly form of African sleeping sickness . Despite the protective role of APOL1 variants in the context of infectious disease, these variants are deleterious in a chronic disease context: through unknown mechanisms, variants increase the risk of nephropathy in African Americans [APOL1 risk variants [APOL1 do influence the subfraction distribution and either this alteration or another variant-provoked change perturbs kidney function, these findings may offer an explanation for our results. Other potential explanations include an effect of the variant on eGFR that leads to downstream changes in HDLc or that the variant separately affects these two quantities. Unraveling the biological mechanisms underlying the observed associations is beyond the scope of this study design, but further work in this area is urgently needed as insights into this relationship may have significant impact on screening and treatment of kidney disease in African Americans.mericans . In thisvariants . As in oThe reason for the lack of interaction in West Africans (despite their genetic similarity), is unclear, though there are numerous differences between these populations that could be further explored. The distributions of eGFR and HDLc are different in AA compared to WA, even after adjustment for known covariates , suggestAPOL1 genotype in African Americans was also stronger in women. While most previous studies do not report an evaluation of gender differences in HDL-kidney function, a stronger association was observed among women in two recent studies that observed an inverse association of HDLc and kidney function [APOL1 genotype [Of interest, there was evidence of a gender effect in this analysis. Specifically, among the African Americans, European Americans, and the Han Chinese, stronger associations were observed in women and the difference in the HDLc-eGFR association by function , 17. A ffunction . This enfunction . Althouggenotype .Population-level differences are subject to a wide array of potentially confounding factors, making a claim of differences by ancestry difficult to assert with confidence. Although there are dramatic differences in environmental exposures and lifestyle factors among the groups considered here, further consideration yields support for ancestry differences. First, all models were adjusted for smoking, alcohol use, and BMI; three factors that vary importantly among groups and could potentially affect both HDL and eGFR . Additionally, potentially confounding lifestyle and cultural factors are not similar between the African American and West African populations in which the HDLc-eGFR association is consistent. While smoking, for instance, is very high among African Americans, it is barely present in the West Africans. Obesity rates are likewise, very different between West Africans and African Americans, as are comorbidities, alcohol use, and lipid-lowering medication use . It is difficult to imagine a lifestyle factor that would be more highly correlated among African Americans and West Africans than between African Americans and European Americans, and could explain the observed pattern of association. Given the similar ancestry but different environmental exposures of African Americans and West Africans, the consistently observed inverse association between HDLc and eGFR supports the inference of a role of shared genetic factors.Our investigation has some notable strengths: (1) the three studies were all designed by the same researchers, with the questionnaires in use intentionally designed to be comparable, insofar as possible given the different cultural context of the questions; (2) having both an African American population as well as a West African ancestral population provides an excellent opportunity to examine complex disease risk in the context of similar ancestral background and highly different lifestyle and cultural exposures. Some limitations of this study that may or may not directly influence the interpretation of the observed findings are worth discussing: (1) we made no adjustment for socioeconomic factors such as education or income as neither the values nor the implications of the values in the societal context were expected to be comparable between studies ; (2) the cross-sectional nature of this analysis makes it impossible to establish whether the observed associations result from an effect of reduced GFR on HDLc concentration or an effect of raised HDLc on eGFR; (3) HDL was not characterized in terms of proinflammatory or pro-oxidant capacity or particle size, characteristics which may be key in understanding the observed relationships. However, in the studied populations, the distribution of lifestyle characteristics that would be expected to influence oxidant or inflammatory status of HDL is not consistent with these being an explanation for the observed results: the rates of pro-oxidant factors (smoking and obesity) are high in the urban African American sample, smoking is also quite high in the Han Chinese (in whom a positive association was observed), and smoking rates are very low and BMI distribution more moderate in the West Africans (in whom the strongest inverse association was observed). Finally, replication in another sample of African Americans is necessary to confirm the observed interaction between rs73885319 and HDLc.APOL1 modifies the HDLc-eGFR association in African Americans with a strong inverse association observed in those with the risk genotype, while no association was observed among those without the risk genotype. Further work investigating the role of APOL1 variants in kidney disease should explore the effects of APOL1 on HDLc.In summary, this analysis reports the association of serum lipids with kidney function in diverse populations. The direction of the association between HDLc and eGFR varies by ancestry, with a positive association observed in Han Chinese and European Americans, and an inverse association in West Africans and African Americans. While the factors behind these population-level differences are unknown, a nephropathy-associated variant in


Coronary chronic total occlusion (CTO) is the last stage of coronary artery atherosclerosis. Percutaneous coronary intervention (PCI) is a therapeutic procedure used to recanalize vessels with total occlusion. However, successful recanalization of CTO is still not optimal, and the key influence factors are still uncertainty. Therefore, a scientific evaluation on the effective of PCI for CTO treatment is necessary.I2 test, Q test, L’abbe and Galbraith. Comprehensive Meta -Analysis 2.0 and Metanalysis 1.0 were used for statistics analysis in this research.Relevant studies of PCI treatment for CTO were examined. Data were extracted and assessed by two independent clinical experts. Embase, PubMed and Medline et al. were used as database. The main research key words include “CTO”, “PCI”, “Stent”, “Reopen”, “long-term”, “follow-up” and “outcome”. Quality assessment was carried out according to the Cochrane Handbook. The selected data were pooled and analyzed using fixed-effect model and random-effect model. Heterogeneity was assessed using the A total of 16 articles involving 6695 cases in successful CTO recanalization (CTO success group) and 2370 cases in failed CTO recanalization(CTO failure group) were included in this research. Low CTO success was associated with elder age, previous coronary artery bypass graft surgery (CABG) history, multi-vessel diseases and right coronary artery disease lesion. Six follow-up variables including major adverse cardiac events (MACE), recurrent myocardial infarction (MI), all-cause death, incidence of angina, subsequent CABG and cumulative survival rate were found significantly reduced associated with CTO success.Clinical baseline characteristics such as age, previous CABG history and lesion baseline characteristics such as lesion length, multi-vessel diseases might be important factors influencing the successful rate of CTO recanalization. Compared to CTO failure patients, all six follow-up variables showed advantage for CTO success patients. Coronary chronic total occlusion (CTO) is the last stage of coronary artery atherosclerosis, accounting for one third of the disease confirmed by coronary angiography. CTO exiThe success of the recanalization for CTO in coronary interventions is vital. HoweverIn this study, publications on PCI procedure in CTO patients were systematically reviewed and suggTwo investigators independently searched Embase, PubMed, Medline, Ovid, CCTR, CNKI, CMBdisc, and with additional manual search for related meeting abstracts and websites including American Heart Association American College of Cardiology, European Society of Cardiology, and national postgraduate thesis pool (from January 1990 to December 2009). The main research key words include “CTO”, “PCI”, “Stent”, “Reopen”, “long-term”, “follow-up” and “outcome”. No language restrictions were used. The inclusion criteria for selected studies comprised: 1) patients with CTO diseases, 2) comparisons of recanalization after PCI and unsuccessful recanalization and 3) the follow-up period of articles were at least one year. Studies with incomplete data or cases number less than 50 were excluded from the analysis.Clinical results with prespecified data forms were selected by two independent investigators. Meta-analysis was conducted by two independent clinical experts and the data was pooled by fixed-effect model and random-effect model.Two independent investigators assessed the quality of eligible articles according to the Cochrane Handbook with est2 test, P < 0.10 and I2 > 50% suggesting significant heterogeneity, I2 ≤ 25% considering low heterogeneity. Searching Software for analysis were Comprehensive Meta-Analysis 2.0 and Metanalysis 1.0.The 95% confidence interval (CI) were calculated from abstracted dichotomous data of each study and pooled according to fixed-effects (inverse-variance weighted) and random-effects (DerSimonian and Laird) models. Statistical heterogeneity was assessed with Cochran’s Q via a chi-square test and quantified with the IA total of 16 reports-32 durinI2 = 50.655%)  history) and six lesion baseline characteristics  were analyzed to assess discrepancies between two treatment groups. Among these, weighted average age difference between two groups was 0.083  between CTO success group and CTO failure group. Six follow up variables including MACE, MI, all-cause death, angina pectoris, subsequent CABG and accumulative survival rate were analyzed. CTO success rate was associated with significant reduction in MACE  and 2370 cases in failed CTO recanalization (CTO failure group) were included in this research. All the articles were used to identify the factors that influenced the PCI procedure outcome leading to a successful CTO recanalization or failed CTO recanalization. Finally, the clinical baseline characteristics such as age, previous CABG history and lesion baseline characteristics such as lesion length, multi-vessel diseases were considered being the important factors influencing the successful rate of CTO recanalization. Compared to CTO failure patients, the six follow-up variables  showed advantage for CTO success patients.A lot of strategies and devices have been developed for a cure of CTO, but the success rate for each treatment is not consistent. PreviouAlthough intervention studies that contain only randomized trials as observational studies are not designed for causal inference, observational studies itself also provide information that may suggest important message in certain circumstance. CompareThe factors including age and CABG history as well as the baseline lesion level (lesion length and multi-vessel diseases) might be the important factors influencing the successful rate of CTO recanalization. The in-hospital mortality, MACE, and incidence of subsequent CABG for PCI procedure were significantly lower in the CTO success group compared with those in the CTO failure group. All six follow up variables  showed an advantage for CTO patients with a successful recanalization of occlusions.CTO: Coronary chronic total occlusion; PCI: Percutaneous coronary intervention; CABG: Coronary artery bypass graft surgery; MACE: Major adverse cardiac events; MI: Myocardial infarction; NCDR: National Cardiovascular Data Registry; PCI: Percutaneous coronary intervention; CI: Confidence interval.The authors declare that they have no competing interests.RL, SY, LT carried out the studies, RL, HC, SG participated and drafted the manuscript. RL, WH, HL carried out the immunoassays. JD, QG, WF participated in the sequence alignment. RL, SG, HL participated in the design of the study and performed the statistical analysis. LT, SY, YY, WF conceived of the study, and participated in its design and coordination and helped to draft the manuscript. All authors read and approved the final manuscript.


VEGF-A) polymorphisms with age-related macular degeneration (AMD) and to perform a meta-analysis.In the present work, the aim was to systematically review all studies about the association of vascular endothelial growth factor A , VIP (Chinese), and the Chinese National Knowledge Infrastructure databases up to October, 2011. A meta-analysis was conducted using Stata software, version 11.0.VEGF-A gene  were performed. This meta-analysis revealed moderate evidence supporting an association between the VEGF-A polymorphisms and AMD. For rs1413711, the TT genotype was associated with an increased risk of overall AMD  1.74, 95% confidence interval (CI) 1.22–2.48) and of wet AMD  model, OR 1.63, 95% CI 1.13–2.35). For rs833061, the C allele  and CC genotype  were the risk factors for overall AMD, while the C allele was also associated with an increased risk of wet AMD . No association was observed between AMD risk and the variant genotypes of VEGF-A rs2010963 and rs3025039 polymorphisms in different genetic models.A total of nine studies with 2,281 AMD cases and 2,820 controls met our eligibility criteria, and meta-analyses of four polymorphisms of the VEGF-A rs1413711 and rs833061 polymorphisms may contribute to AMD susceptibility.The results suggest the  Age-related macular degeneration (AMD) is the most common cause of blindness, particularly irreversible blindness, in elderly people worldwide . A recenHistopathologically, GA is usually the consequence of the loss of the RPE cell layer and overlying retinal photoreceptors, resulting in thinning of the retina and progressive visual impairment . Wet AMDVEGF-A gene may be important in regulating VEGF-A protein production and/or influencing mRNA splicing. Previous studies report that VEGF-A −460T/C and +634G/C were found to be associated with the risk of AMD in Caucasian AMD populations [VEGF-A gene may thus have an important role in determining and/or modifying the development and progression of AMD and the response to anti-VEGF therapy.Vascular endothelial growth factor (VEGF) is a key molecule in promoting angiogenesis and potentially inducing vascular leakage and inflammation by triggering the increased production and permeability of capillary endothelial cells . The VEGulations -15, and ulations . GeneticVEGF-A gene is located on chromosome 6p21.3 and contains eight exons and seven introns [VEGF-A gene and are believed to have functional activity [rs833061) in the promoter region, +405G/C (rs2010963) in the 5′-untranslated region, and +936C/T (rs3025039) in the 3′-untranslated region are known to modulate the protein expression of VEGF-A [The  introns . Severalactivity . Among tf VEGF-A ,19.VEGF-A polymorphisms and AMD susceptibility. However, these studies were limited by small or moderate sample sizes. Meta-analysis can be used to pool data from the appropriate individual studies to obtain sufﬁcient statistical power to detect the potential effect of small to moderate sizes of samples associated with these polymorphisms. To address these issues, we performed a systematic review and meta-analysis of all eligible case-control studies to estimate the association between VEGF-A polymorphisms and AMD risk.Over the past decade, a considerable number of epidemiological studies have focused on the association between To identify the studies eligible for systematic review and meta-analysis, the following electronic databases were searched: PubMed, Embase, Wanfang (Chinese), VIP (Chinese), and the Chinese National Knowledge Infrastructure (CNKI), up to October 19, 2011. The following keywords were used:  AND (haplotype OR polymorphism) AND (macular degeneration). The search was done without restrictions on language and included all studies conducted on human subjects. Additional studies were identified through a manual search of the references of the original studies. Of the studies with overlapping data published by the same investigators, only the most recent or complete study was included in this meta-analysis.VEGF-A polymorphisms and AMD risk, (ii) they were case-control or cohort studies, and (iii) they contained sufficient published data to estimate an odds ratio (OR) with a 95% confidence interval (CI). Following the application of these criteria, meta-analyses were performed for all polymorphisms for which eligible data were reported in at least three published studies.Studies had to meet all of the following criteria: (i) they evaluated VEGF-A polymorphisms. Ethnic origins were categorized as Caucasian, Asian, and African. If a study did not state the ethnic descendent or if it was not possible to separate participants according to such phenotypes, the group was termed “mixed.” Late AMD was divided into two subtypes: dry AMD  and wet AMD .Information was carefully extracted by two independent investigators according to the inclusion criteria noted above. For each study, the following information was collected: the first author’s surname, year of publication, country of origin, ethnicity, mean age and type of cases and controls, and the number of cases and controls for each genotype of VEGF-A polymorphisms and AMD risk were calculated using ORs and 95% CIs. The genetic model analysis was performed according to the Thakkinstian et al. [Z test, in which p<0.05 was considered significant. Between-study heterogeneity was estimated using the χ2-based Q statistic [2>50% [p values.To test for control population selective bias, a chi-square test was applied to determine if the genotype distribution of the control subjects of each individual population conformed to the Hardy-Weinberg equilibrium . Associations between n et al.  method, tatistic . Heterogc [2>50% . If heteVEGF-A polymorphisms and AMD risk [Eighty potentially relevant papers were retrieved . Sixty-seven studies were subjected to a full-text review and excluded according to the selection criteria stated above. Thirteen studies were identified that examined the association between AMD risk -16,23-31AMD risk ,29-31. AAMD risk ,16,23-28AMD risk , the IntAMD risk , the AgeAMD risk , and othAMD risk ,23,25,28VEGF-A gene . The lists of genotypes and allelic frequencies of these four VEGF-A polymorphisms in the eligible studies are provided in rs2010963 polymorphism significantly deviated from HWE (p<0.05).These studies focused on 20 identified polymorphisms of the F-A gene : rs69994rs1413711 SNP (+674C/T) is located in intron 1 of the VEGF-A gene (1695 bp downstream from the start of exon 1) and has been investigated in association studies in patients with AMD, particularly wet AMD. A positive association was initially reported by Churchill et al. [rs1413711 polymorphism of the VEGF-A gene and AMD. More recently, Almeida et al. [The a et al.  and Qu ea et al.  reportedrs1413711 polymorphism of the VEGF-A gene comprised three different populations, including 554 AMD cases and 551 controls. An evaluation of the association between the VEGF-Ars1413711 polymorphism and AMD risk is presented in VEGF-Ars1413711 TT genotype was associated with a significantly increased AMD risk in the TT versus the CT model . No significant results were observed in any other genetic models. In the stratified analysis for wet AMD, the VEGF-Ars1413711 TT genotype was also associated with a significantly increased wet AMD risk in the TT versus the CT model  and the TT versus the CC+CT model  is located in the promoter region of the VEGF-A gene. A pioneer study by Richardson et al. [rs833061 polymorphism of the VEGF-A gene was not associated with dry or wet AMD. Furthermore, two studies [The n et al.  of a Cau studies ,23 of a  studies  reportedVEGF-Ars833061 C allele among subjects with wet AMD  for whom detailed allele frequencies were reported, including 1,180 cases and 611 controls. Overall, significant associations were found for the C allele versus the T allele , and for the CC versus the TT model  is located in the 5′-untranslated region of the VEGF-A gene. Studies by Lin et al. [rs2010963 polymorphism of the VEGF-A gene and AMD. Janik-Papis et al. reported positive associations of the C allele, CC genotype, and the occurrence of dry AMD [The n et al.  and Qu en et al.  of two C dry AMD .A meta-analysis of an association in three studies of AMD patients (614 cases and 454 controls from one Caucasian population and two Asian populations) did not show a significant association in any of the genetic models of the overall comparison or in the stratified analysis for wet AMD . A sensirs3025039 allele (+936C/T) is located in the 3′-untranslated region of the VEGF-A gene. The three studies [rs3025039 polymorphism of the VEGF-A gene comprised three different populations, including 575 AMD cases and 568 controls from one Caucasian population and two Asian populations. Lin et al. [rs3025039 SNP was significantly increased in Chinese wet AMD patients compared with controls. However, this association was not replicated in the other groups, i.e., in one Caucasian population [The  studies ,23,26 win et al.  reportedIn an overall comparison of three studies, there was no association between this polymorphism and the risk of AMD in any of the genetic models . Due to The Begg’s rank correlation method and Egger’s weighted regression method were used to assess publication bias. No obvious publication bias for these polymorphisms was found.VEGF-A SNPs in terms of AMD risk predisposition in different ethnic populations, but the results have been conflicting [rs1413711 CC genotype was significantly associated with an increased susceptibility to AMD in a Caucasian population. Richardson et al. [VEGF-A gene and found no evidence of an association between these SNPs and either AMD or any of its subtypes in an Australian population. Lin et al. [VEGF-A gene with the risk of AMD in Chinese patients. Lin et al. [rs3025039 allele was significantly associated with wet AMD. However, Qu et al. [The VEGF-A protein is the most important regulator of angiogenesis and is overexpressed in the retinal tissue of AMD, particularly wet AMD -9. Polymflicting -16,23-31flicting  found thn et al.  investigVEGF-A polymorphisms and AMD risk by critically reviewing nine studies, including a total of 2,281 AMD patients and 2,820 controls. These studies focused on 20 identified polymorphisms of the VEGF-A gene, but only four polymorphisms  were reported in at least three published studies.In the present study, a systematic review/meta-analysis was performed to examine the association between the rs1413711 polymorphism, also called +674C/T, is located in intron 1 of the VEGF-A gene. Thus far, no data are available regarding the functional activity of this polymorphism. Our meta-analysis on the available studies showed the VEGF-Ars1413711 TT genotype was associated with a significantly increased AMD risk. People who had the rs1413711 TT genotype had a 74 percent higher risk of AMD than people who had the CT genotype. In the stratified analysis by subtypes of AMD, it was also found that the rs1413711 TT genotype was a risk factor in wet AMD patients. The TT genotype carriers had a nearly 82 percent increased risk of wet AMD compared with the CT genotype carriers, and had about a 63 percent increased risk of wet AMD in the recessive model (TT versus CC+CT). Previous studies have suggested VEGF is a pathogenic factor in the development of CNV [rs1413711 polymorphism and the influence of the TT genotype on the pathogenesis and clinical treatment of AMD, particularly wet AMD.The t of CNV . Churchirs833061 allele (−460 T/C) is located in the promoter region of the VEGF-A gene and the T allele may be associated with decreased promoter activity of the VEGF-A gene [rs833061 C allele had a 72 percent higher risk of AMD compared with individuals with the rs833061 T allele, and those with the CC genotype had a 77 percent higher risk of AMD compared with those with the TT genotype. In the stratified analysis for wet AMD, the C allele carriers had about a 54 percent increased risk of wet AMD compared with the T allele carriers, demonstrating a significant effect of the C allele on the increased risk for wet AMD. However, in the stratified analysis for dry AMD, no significant associations were observed in any of the genetic models. This suggests a potential difference in etiologic mechanisms and the clinical response of anti-VEGF therapy between dry AMD and wet AMD. Agents that block the effects of VEGF are emerging as the most successful treatment for wet AMD [rs833061 polymorphism is potentially a risk factor for AMD, and the association between this SNP genotype and the clinical response of anti-VEGF treatment requires further study. Moreover, the sample size, especially of dry AMD, in the present study was still limited and potential small genetic effects may not be detectable. Such findings warrant further studies with larger samples and more homogenous populations.The F-A gene . In the  wet AMD -34. The VEGF-Ars2010963 and rs3025039 polymorphisms were not a risk factor for AMD. When stratifying for the subtype of the disease, there were no significant differences in genotype distribution between wet AMD cases and controls.In this meta-analysis, it was found that the It should be noted that there were some limitations in this study. First, because of the limitations of raw data and publication, some relevant studies were excluded from this meta-analysis. Second, the sample sizes in the analyses were extremely small. Third, the sources of heterogeneity that existed among studies for most polymorphisms were not addressed. Finally, this meta-analysis was based on unadjusted data, while a more precise analysis could be performed if individual data were available.rs833061 in the VEGF-A gene are associated with an increased risk of overall AMD, and the TT genotype of rs1413711 and the C allele of rs833061 are a risk factor in wet AMD. VEGF-Ars2010963 and rs3025039 polymorphisms show no association with AMD risk. More detailed and well designed studies with larger populations and different ethnicities are needed to further evaluate the associations.In conclusion, despite the above-mentioned limitations, this meta-analysis suggests the TT genotype of rs1413711 and the C allele and the CC genotype of


To conduct a systematic review of observational studies on the risk of acute myocardial infarction (AMI) with use of individual nonsteroidal anti-inflammatory drugs (NSAIDs).A search of Medline (PubMed) for observational studies published from 1990 to 2011 identified 3829 articles; 31 reported relative risk (RR) of AMI with use of individual NSAIDs versus nonuse of NSAIDs. Information abstracted in a standardized form from 25 publications was used for the meta-analysis on 18 independent study populations.Random-effects RR ) was lowest for naproxen 1.06 (0.94–1.20), followed by celecoxib 1.12 (1.00–1.24), ibuprofen 1.14 (0.98–1.31), meloxicam 1.25 (1.04–1.49), rofecoxib 1.34 (1.22–1.48), diclofenac 1.38 (1.26–1.52), indometacin 1.40 (1.21–1.62), etodolac 1.55 (1.16–2.06), and etoricoxib 1.97 (1.35–2.89). Heterogeneity between studies was present. For new users, RRs (95% CIs) were for naproxen, 0.85 (0.73–1.00); ibuprofen, 1.20 (0.97–1.48); celecoxib, 1.23 (1.00–1.52); diclofenac, 1.41 (1.08–1.86); and rofecoxib, 1.43 (1.21–1.66).Except for naproxen, higher risk was generally associated with higher doses, as defined in each study, overall and in patients with prior coronary heart disease. Low and high doses of diclofenac and rofecoxib were associated with high risk of AMI, with dose–response relationship for rofecoxib. In patients with prior coronary heart disease, except for naproxen, duration of use ≤3 months was associated with an increased risk of AMI.Most frequently NSAIDs used in clinical practice, except naproxen, are associated with an increased risk of AMI at high doses or in persons with diagnosed coronary heart disease. For diclofenac and rofecoxib, the risk was increased at low and high doses. Copyright © 2013 John Wiley & Sons, Ltd. The cardiovascular safety of nonsteroidal anti-inflammatory drugs (NSAIDs) is still under scrutiny after the introduction of selective cyclooxygenase-2 (COX-2) inhibitors.Syntheses of published interventional and observational studies conclude that both selective and nonselective COX-2 inhibitors increase the risk of acute myocardial infarction (AMI), and this risk varies across individual NSAIDs.9http://www.sos-nsaids-project.org).Within the Safety of NSAID (SOS) project, a research and development project funded by the Directorate General of Research and Innovation of the European Commission under the Seventh Framework Programme, we performed a quantitative systematic literature review of observational studies assessing the risk of cardiovascular events associated with the use of NSAIDs. (We performed a systematic literature search on cardiovascular events in the Medline database (PubMed) using free-text search terms and Medical Subject Headings for myocardial infarction, acute coronary syndrome, sudden cardiac death, stroke, heart failure, left ventricular dysfunction, and nonsteroidal anti-inflammatory agents . We examined references of articles for additional sources.Eligible studies for review were observational cohort or case–control studies published in peer-reviewed journals from January 1, 1990, through May 4, 2011. Our search period started in 1990 because the first epidemiology study on the risk of AMI and NSAIDs was published in 2000.6We used the Newcastle-Ottawa ScaleUsing a standardized form, we extracted the odds ratio (OR) or relative risk (RR) for each individual NSAID estimated in each study from the model that was adjusted for the largest number of factors. The main analysis was conducted on all subjects exposed to individual NSAIDs and all types of AMI events. A dose–response analysis used the reported low-medium and high-dose estimates from each study. Data were limited for the evaluation of the effect of duration for individual NSAIDs. We performed several sensitivity analyses.2χ test of homogeneity. Tau2 was used to quantify the between-study variance for random-effects models. The Higgins 2I statistic was used to describe the percentage of between-study variability in effect estimates attributable to true heterogeneity rather than chance. The 2χ test was used to test for homogeneity between subgroups. Publication bias was examined by review of funnel plots. The analysis was conducted using Review Manager soft ware .We estimated pooled RRs and 95% CI for the effect of each NSAID with at least three point estimates from independent studies, using the inverse variance weighting method.For inclusion in the meta-analysis, studies were required to provide measures of association comparing the risk of AMI between users of individual NSAIDs and nonusers or remote NSAID users. The broad search identified 3829 articles; after initial exclusions, the full text of 85 articles was reviewed . A totalAll except six studies16The random-effects summary estimate  of the risk of AMI was lowest for naproxen , followed by celecoxib  and ibuprofen . Meloxicam , rofecoxib , diclofenac , indometacin , etodolac 1.55; 1.16–2.06), and etoricoxib  were associated with an increased risk of AMI . Fixed m–2.06, an20The pooled estimates  for new users were estimated for naproxen , ibuprofen , diclofenac , celecoxib , and rofecoxib  . The sumRestricting the analysis to studies that included out-of-hospital (community) coronary heart disease deaths in the definition of AMIP = 0.03),Studies covering early periods after the introduction of COX-2 inhibitors (from 1999 to 2002) yielded, for celecoxib, significantly lower summary RR (95% CI) estimates  than the studies that covered a more extended period, through 2005,  .Overall, 11 studies reported the effect of individual NSAID dose on the risk of AMI.Forest plots for the risk of AMI by dose for naproxen, ibuprofen, celecoxib, diclofenac, and rofecoxib compared with nonusers are in Few studies reported on the effects of treatment duration on the risk of AMI.Except for naproxen, the estimates of risk for each of the evaluated individual NSAIDs in the subgroup of shorter duration were associated with an increase of AMI in patients with prior history of coronary heart disease .2 = 4.96; p = 0.03).Five studies presented analysis results in patients using aspirin concomitantly with the most frequently used individual NSAIDs,The funnel plots generated by graphing RR against the standard error of the log of RR appear quite symmetric for all five of the individual NSAIDs . Relatively few small studies were identified, and all of them found null associations (except for celecoxib in one study). As expected, in a few cases, some of the smaller studies had more extreme RR; this does not necessarily suggest publication bias but instead could reflect that the smaller study was of lesser quality or was perhaps conducted among a particularly high-risk population.This meta-analysis of approximately 100 000 AMI events from 18 independent study populations and 64 000 AMI events in the subgroup analyses supports variability in the risk of AMI associated with current use of the most frequently used NSAIDs in comparison with nonuse of NSAIDs. Except for naproxen, almost all NSAIDs most frequently used in clinical practice, if used at high doses or in populations with prior CHD, are associated with an increased risk of AMI. Rofecoxib and diclofenac used at either low or high doses are associated with an elevated risk of AMI, but higher doses of rofecoxib are associated with higher risk of AMI than low doses.5. High-dose regimens of diclofenac and ibuprofen, but not naproxen, were associated with similar excess risk. The authors acknowledged that the quality of the reported safety data from these trials was suboptimal. Poor quality of reported safety data in clinical trials prevented pooling of results.38Our results were consistent with those of previous meta-analyses. Meta-analyses of randomized clinical trials reported an increased risk of vascular events associated with selective COX-2 inhibitors, largely attributable to a two-fold increased risk of AMIEstimated risks of AMI were of similar magnitude and trend to those estimated in prior meta-analyses of observational studies but provide further insights on dose effects and effects in populations with prior coronary heart disease.Our meta-analysis was restricted to acute coronary events occurring in independent populations. A separate publication reported the results of a meta-analysis on the risk of all subtypes of stroke and ischemic stroke associated with the use of individual NSAIDs.The extent of COX-2-dependent prostacyclin inhibition may represent an independent key determinant of the increased thrombotic risk with NSAIDs in the presence of insufficient COX-1 activity < 95%) to inhibit platelet function.5% to inhMost of our analyses detected heterogeneity between effect estimates obtained across studies for all the frequently used NSAIDs. We reported random-effects estimates, as recommended in the context of substantial heterogeneity, and for some individual NSAIDs, Tau-squared was still acceptable.The main limitations of the present meta-analysis descend from the limitations of each of the included studies. Observational studies are prone to confounding, selection, and information bias.Residual confounding can be a major limitation for the majority of the included studies since the magnitude of the increased risks was rather small. Residual confounding might be present in studies that failed to systematically record some life style factors. Few studies adjusted the analysis for socioeconomic statusConfounding by indication could have operated in opposite directions over the years. The majority of studies accounted for available baseline risk factors for cardiovascular disease. Bias by contraindication to patients with high cardiovascular risk would be minor because only one study included time after the withdrawal of rofecoxib.Protopathic bias may occur if exposure to the drug of interest started, stopped, or changed because of an unrecognized manifestation of the disease under study. 17survival bias and by the inability to control for risk factors that may be modified by NSAIDs.Inclusion of prevalent NSAID users leads to immortal time bias since occurrence of the outcome after the first NSAID prescription was not captured and the unexposed person-time before the start of follow-up of the exposed cohort was not accounted for, which could have underestimated rate ratios comparing the rate of AMI events during current NSAID use with rates during NSAID nonuse.48One study was affected by causal intermediate factor since it can be an effect of NSAIDs and is an established risk factor for AMI. Thus, adjusting for hypertension or for the use of concurrent antihypertensive medications during follow-up could underestimate RR.Hypertension can be considered a recall or information bias, which results from differential misclassification of exposure between cases and controls. In one study, the time window to recall the exposure was different for cases than for controls, which may have underestimated the RR.Field case–control studiesMisclassification of exposure may be present since information on the use of over-the-counter (OTC) drugs is not recorded in electronic data. A study assessed use of low-dose aspirin and OTC NSAIDs through a standardized telephone survey and did not find differences in the use of OTC drugs between the individual NSAIDs studied.Our subgroup analysis of individual NSAIDs stratified by the concomitant use of aspirin was based on few studies. These very limited results suggested that concomitant use of aspirin might mitigate some, but not all, of the increased risk of AMI associated with diclofenac and likely with rofecoxib. Further evaluation is warranted.Results from observational studies in this meta-analysis confirm variability of effect of individual NSAIDs on the risk of AMI and that almost all of the NSAIDs most frequently used in clinical practice, except naproxen, are associated with an increased risk of AMI at high doses or when used in persons with diagnosed preexisting coronary heart disease. For diclofenac and rofecoxib, this increased risk is present both at low and high doses.Ongoing large studies, such as the multi-database observational study within the SOS project, might help to elucidate the risk of AMI associated with individual NSAIDs used in different European populations, by dose and duration. Individual studies within this project were performed with similar study design and definitions to minimize heterogeneity across study populations and databases.


CYP2C9, ABCC8/KCNJ11, and TCF7L2 were associated with the effect of sulfonylureas. CYP2C9 encodes sulfonylurea metabolizing cytochrome P450 isoenzyme 2C9, ABCC8 and KCNJ11 genes encode proteins constituting ATP-sensitive K+ channel which is a therapeutic target for sulfonylureas, and TCF7L2 is a gene with the strongest association with type 2 diabetes. SLC22A1, SLC47A1, and ATM gene variants were repeatedly associated with the response to metformin. SLC22A1 and SLC47A1 encode metformin transporters OCT1 and MATE1, respectively. The function of a gene variant near ATM gene identified by a genome-wide association study is not elucidated so far. The first variant associated with the response to gliptins is a polymorphism in the proximity of CTRB1/2 gene which encodes chymotrypsinogen. Establishment of diabetes pharmacogenetics consortia and reduction in costs of genomics might lead to some significant clinical breakthroughs in this field in a near future.Oral antidiabetic drugs (OADs) are used for more than a half-century in the treatment of type 2 diabetes. Only in the last five years, intensive research has been conducted in the pharmacogenetics of these drugs based mainly on the retrospective register studies, but only a handful of associations detected in these studies were replicated. The gene variants in  Type 2 diabetes (T2D) affects more than 5% of population of the developed countries and its prevalence increases worldwide . The majThere is a considerable variability in the effect of antidiabetic drugs. This variability is caused by nonbiological and biological factors. Among nonbiological factors, psychological and social factors play an important role. These include compliance to medication, variable access to health care, and physician prescribing practices which are dependent on both international and national guidelines. Biological factors are related to pharmacokinetics and pharmacodynamics of drugs. Biological factors might be nongenetic, such as the influence of intestinal, hepatic and renal functions, or drug interactions predominantly on pharmacokinetics of drugs. Pharmacogenetics focuses on the study of genetic factors which influence the effect and side effects of different drugs with the final aim of personalizing the treatment of T2D. While clear implications for clinical practice based on pharmacogenetic knowledge exist only for some forms of monogenic diabetes [The optimal design of pharmacogenetic studies requires attention to some key methodological issues. Whilst the ideal study is a prospective genotype-blind study design with adequate statistical power, these are very costly, time-consuming and often require participation of multiple centers. Therefore, the majority of studies published used retrospective data retrieved from registers and databases. In the retrospective studies, it is possible to achieve reasonable sample sizes for pharmacogenetic studies, but it can be difficult to adjust for all confounding variables as these may not have been measured. However, as most confounding should not be genotype dependent, this should not be a major issue.  With respect to the outcomes used in pharmacogenetic studies, there are two main types of endpoints. Pathophysiological endpoints reflect the effect of gene variants on insulin resistance or insulin secretion. Such studies may yield novel knowledge on the role of different gene variants in the pathogenesis of T2D, but their clinical applicability might be limited. Thus, from the point of view of possible clinical implications, endpoints such as reduction of HbA1c, fasting plasma glucose, and postprandial plasma glucose are of the highest importance. Among them, both an achievement of therapeutic target of HbA1c<7% defined in guidelines and a reduction in HbA1c seem to be the most appropriate endpoints for pharmacogenetic studies in T2D . Different factors may confound the relationship between the studied gene variants and endpoints. When using achievement of HbA1c<7% or reduction in HbA1c as an endpoint, the strongest confounder is the baseline level of HbA1c, as it was shown in both the meta-analysis of clinical trials and also in the individual pharmacogenetic studies , 5. ThatWe selected studies discussed in this review taking into account the above mentioned methodological aspects of pharmacogenetic studies in patients with T2D. We performed a search in the MEDLINE and Web of Knowledge databases using “pharmacogenetics OR pharmacogenomics” keyword in combinations with the names of groups of antidiabetic drugs or generic names of individual antidiabetic drugs. In the present review, we will discuss the mechanisms of associations between gene variants and the drug effect in the healthy subjects, in cell lines and in the patients with T2D. The studies which examined the effect of gene variants on the indices of glucose control will be presented only when at least 100 patients with T2D are included in the study.β-cells. Sulfonylureas have been used for more than a half-century, while nonsulfonylurea secretagogues meglitinides (glinides) have been used for approximately the last 15 years in the treatment of T2D. The most common side effects of both groups of drugs are hypoglycemia and weight gain. While previously sulfonylureas were considered as first-line treatment in less obese patients with T2D, more recent guidelines recommend both groups of drugs mainly in combination therapy with metformin as a second-line treatment [Insulin secretagogues stimulate secretion of insulin from the pancreatic reatment . CYP2C9 [CYP2C9*1. Two common nonsynonymous variants Arg144Cys (CYP2C9*2) and Ile359Leu (CYP2C9*3) were identified [Sulfonylureas are metabolized in the liver primarily by cytochrome P450 isoenzyme 2C9 encoded by CYP2C9 –10. The entified . Studiesentified , 10. CYP2C9  variants with therapeutic response to sulfonylureas was Genetics of Diabetes Audit and Research Tayside Study (GoDARTS) which included 1073 patients treated with sulfonylureas. The 6% of the population who were carriers of two loss-of-function alleles (*2/*2 or *2/*3 or *3/*3) had a 0.5% greater reduction in HbA1c compared with wild-type homozygotes (P = 0.003) and were 3.4 times more likely to achieve on-treatment HbA1c<7% (P = 0.009) [ The first robust study to confirm association of n = 172), there was a significant difference in daily prescribed dose observed between genotypes. While the prescribed dose of tolbutamide increased in the carriers of *1/*1, *1/*2, or *2/*2 genotypes, there was very little tolbutamide dose increase in patients with *1/*3 or *2/*3 genotypes (P = 0.009) [P = 0.07) was observed in the carriers of the CYP2C9*3 allele [Further studies in patients with type 2 diabetes used indirect endpoints of sulfonylurea effect such as prescribed dose of sulfonylurea. Becker et al. analyzed 475 elderly patients included in the Rotterdam study who started sulfonylurea treatment. In the largest subgroup of patients treated with tolbutamide (= 0.009) . In a si3 allele . CYP2C9  influence also pharmacokinetics of nonsulfonylurea secretagogue nateglinide [CYP2C8 is associated with pharmacokinetics of repaglinide [SLCO1B1, the gene encoding organic anionic transporter B1 (OATPB1) [Studies in healthy volunteers showed that variants in eglinide , while vaglinide . Pharmac(OATPB1) . ATP) channel plays crucial role in glucose stimulated insulin secretion. In physiologic condition, ATP produced by glucose oxidation in mitochondria leads to closure of KATP channel with subsequent depolarization of β-cell membrane, increased influx of calcium ions, and subsequent release of presynthesized insulin from the β-cell. Insulin secretagogues (both sulfonylureas and glinides) act by inducing KATP channel closure by binding on its constituting proteins. The inner pore of the KATP channel is constituted by four molecules of potassium inward rectifier 6.2 (Kir6.2) while the outside part is created by four molecules of sulfonylurea receptor 1 (SUR1) [The ATP-sensitive potassium (K1 (SUR1) . ATP channel. The A-site is exclusively part of the SUR1 subunit whereas the B-site resides both on SUR1 and Kir6.2 subunits [ Two sulfonylurea binding sites were identified on the Ksubunits . Sulfonysubunits , 19. ATP channel proteins—KCNJ11  (encoding Kir6.2) and ABCC8 (encoding SUR1)—lead to neonatal diabetes mellitus. Breakthrough pharmacogenetic studies showed that sulfonylureas are able to correct the defect caused by KCNJ11 and ABCC8 mutations resulting in patients (believed previously to have type 1 diabetes) being able to transition from long-term insulin therapy to sulfonylurea treatment [KCNJ11 and ABCC8 were logical selection also for pharmacogenetic studies in type 2 diabetes.  Mutations in genes encoding Kreatment , 21. ThuKCNJ11 and S1369A in ABCC8 were mostly studied in pharmacogenetic studies with insulin secretagogues. These two variants are in strong linkage disequilibrium so that any association signal from these two polymorphisms is genetically indistinguishable [Nonsynonymous common variants E23K in uishable . ABCC8 S1369A polymorphism with glycemic control was done in Chinese population. The study included 661 patients who were genotyped for 25 single nucleotide polymorphisms. KCNJ11 rs5210 (different from E23K) and ABCC8 S1369A polymorphisms were significantly associated with decrease in FPG. Association analysis of ABCC8 S1369A with sulfonylurea response was replicated in an independent cohort of 607 patients. In the combined analysis of both cohorts, subjects with a ABCC8 AA genotype had a significantly greater decrease in FPG (P < 0.001) and a 2-hour plasma glucose (P < 0.003), but only a borderline decrease in HbA1c , in comparison with patients with SS genotype [P = 0.044) was observed after adjustment for baseline HbA1c [The most robust study which showed an association of ne HbA1c .KCNJ11  E23K and sulfonylurea efficacy was observed in the study of Javorsky et al. which included 101 patients treated with sulfonylurea after metformin monotherapy failure. In the dominant model, the carriers of the K-allele had higher reduction in HbA1c after 6-month therapy in comparison with EE homozygotes  [In Caucasian population, the association between = 0.036) . KCNJ11 polymorphisms (E23K and L270V) and the response to sulfonylurea. The evaluated outcome was based on two measurements of FPG within the first year of treatment, but not on HbA1c measurements [Previously, two studies did not find such association in Caucasian population. In the United Kingdom Prospective Diabetes Study (UKPDS) population, a group of 363 patients primarily assigned to sulfonylurea treatment was analyzed. No significant relationship was found between two urements . Since tKCNJ11  E23K and therapeutic response to repaglinide. He et al. found in a group of 100 patients treated for 24 weeks with repaglinide that the decrease in HbA1c was higher in patients with EK and KK genotypes than in EE homozygotes  [ Another study in Chinese population examined the association between = 0.022) . The autATP channel resulting in its closure. Studies in cell lines transfected by cloned channels with KCNJ11  K23-ABCC8 A1369 haplotype shed some light on observed differences among different sulfonylureas and glinides to affect insulin secretion in carriers of risk haplotype. K23/A1369 carriers were more sensitive to inhibition of KATP channel by gliclazide and mitiglinide in comparison with E23/S1369 haplotype carriers. In contrast, E23/S1369 carriers were more sensitive to glimepiride, chlorpropamide, and tolbutamide, whilst there was no difference in KATP channel sensitivity between the two haplotypes for glibenclamide, glipizide, repaglinide, and nateglinide [Clinical studies showed higher efficacy of sulfonylurea treatment in risk allele carriers suggesting that, in line with the studies in neonatal diabetes, sulfonylureas and possibly also glinides are able to correct the defect in insulin secretion by binding to the proteins of the Keglinide , 19.TCF7L2) gene are the strongest predictors of increased risk of developing type 2 diabetes, a 40% increased risk per allele [β-catenin, mediates Wnt-signaling, relates to normal development of pancreas during embryogenesis, and affects secretion of glucagon-like peptide 1 (GLP-1) by L-cells in the small intestine [TCF7L2 rs7903146 polymorphism have reduced insulin secretion [β-cell mass, impaired insulin processing or release, and impaired incretin signaling in β-cells [Among more than 50 gene variants associated with T2D, the variants in transcription factor 7-like 2  and rs7903146 (C/T) gene variants and response to sulphonylurea therapy in type 2 diabetic patients. In that study in 901 Scottish patients with type 2 diabetes, subjects with the rs12255372TT genotype had approximately two times higher probability for early sulphonylurea treatment failure (HbA1c>7% within the period of 3–12 months after starting sulphonylurea therapy) compared to those with the CC genotype. In a complementary approach, a linear regression model was used with minimal HbA1c during treatment within a year after sulfonylurea initiation as the dependent variable. The predicted HbA1c on-treatment was for rs1225372 GG genotype 7.0%, while for TT genotype, it was 7.33%. Similar results were observed for rs7903146 [ GoDARTS was the first pharmacogenetic study to address the relationship between the s7903146 .P = 0.006) [P = 0.043). In this study, the adjustment for the baseline HbA1c values was not performed [ Results of this study were replicated by two study groups. Javorský et al. found in a group of 101 Slovakian patients that the reduction in HbA1c after six months of sulphonylurea therapy (ΔHbA1c) was significantly lower in the CT+TT genotype group in comparison with the CC homozygotes for rs7903146 genotype. The absolute difference in ΔHbA1c between the two groups was 0.35% (= 0.006) , that iserformed .Metformin has been used for the treatment of type 2 diabetes mellitus since 1959 and is still the cornerstone in the treatment of this disease. At physiological pH, metformin is positively charged and therefore very hydrophilic, giving it some interesting pharmacokinetic properties . First, ATM gene that were associated with the ability to reach the treatment goal of an HbA1c<7%. The strongest association was with the rs11212617 polymorphism. Participants had a 1.64 times higher change of reaching the treatment goal for each minor allele with a P value of 1.9 × 10−7. The authors subsequently genotyped this polymorphism in two independent populations (another GoDARTS population and the UKPDS population) for replication. And in both populations, a significant association was found with treatment response. The combined effect was 1.35 times higher change of reaching the treatment goal (P = 2.9 × 10−9) for each minor allele. The secondary analysis was the association between this polymorphism and the reduction in HbA1c, and a 0.11% larger reduction in HbA1c per minor allele (P = 6.6 × 10−7) was found in the three cohorts combined. In the replication study by van Leeuwen et al., the rs11212617 polymorphism was studied in three independent populations, the Diabetes Care System (DCS) West-Friesland (n = 929), the Rotterdam Study (n = 182), and the CARDS Trial (n = 254). They used the same endpoint as was used in the initial GWAS by Zhou et al. In the three populations, the combined odds ratio was 1.24 with a P value of 0.016. For the secondary endpoint, the reduction in HbA1c per minor allele, no significant association was found [In GWAS, Zhou et al. genotyped more than 700,000 polymorphisms in 1,024 metformin users from the GoDARTs study . They idas found .The rs11212617 polymorphism has also been genotyped in the at-risk population of the aforementioned DPP trial. However, Florez et al. describe that no association was found between this polymorphism and the incidence of diabetes in the participants randomized to metformin therapy .SLC22A1 gene encoding the OCT1 transporter and the glucose lowering effect of metformin both in animal model and in healthy volunteers. They identified four polymorphisms in the SLC22A1 gene coding for a change in amino-acid sequence  and studied the association with the glucose lowering effect. In the subjects carrying one or more variant alleles, the metformin plasma levels were higher and the glucose lowering effect during a glucose tolerance test was impaired [Shu et al. were the first to study the effect of genetic variation in the impaired , 44. In impaired . For R61impaired . Strikingly, in the largest study in subjects with T2D performed by Zhou et al., no association was found . In thisChristensen et al. studied the effect of eleven polymorphisms in various transporters including OCT1 on the through plasma levels and the glucose lowering effect in 151 diabetes mellitus patients in whom metformin was added to the previous insulin therapy. Patients with one or two variant alleles of 420del had lower trough plasma levels. In this study, two other polymorphisms, G401S and rs461473 in an intronic region not coding for an amino-acid change, were significantly associated with the glucose lowering effect after start with metformin therapy .SLC22A1 gene using tagging polymorphisms and found that the rs622342 polymorphism was significantly associated with the glucose lowering effect in 102 incident metformin users [Two other polymorphisms that have been described in the OCT1 transporter are the rs622342 and the M408V polymorphisms. Becker et al. screened the in users . This rein users . Howeverin users . SLC22A1 gene have been described that occur frequently and have a reduced transporter activity [SLC22A2 gene, is expressed in the basolateral membrane of the renal epithelial cells. In three studies in Asian populations, an association between A270S and renal metformin clearance or plasma lactate concentrations has been described [In Asians, the frequencies of R61C and 420del variants are low and no polymorphisms in the activity . Severalescribed –54. An aescribed . SLC47A1 gene, is strongly expressed in the brush border membrane of the kidney and the bile canaliculi in the liver. It is believed to facilitate the excretion of compounds such as metformin in the urine and bile. Becker et al. were the first to identify that the tagging polymorphism rs2289669 (G/A) was associated with the HbA1c lowering effect in incident metformin users [SLC22A1 gene, identified earlier by this group [r2 ≈ 0, 8) and the effect was consistent in both studies, this is considered as a replication of the previous findings of Becker et al. For the other polymorphisms, no significant associations were found after correction for multiple testing. Metformin is also a substrate for the multidrug and toxin extrusion 1 (MATE1) transporter. This transporter, encoded by the in users . They suis group . Jablonsis group . They raSLC47A1 gene and found that in healthy volunteers, the variant allele resulted in lower glucose levels, and in 145 incident metformin users, it resulted in an increased HbA1c lowering effect [SLC47A1 gene results in higher hepatic plasma levels, due to reduced efflux transporter activity. In patients with a reduced OCT1 influx transporter activity, the hepatic plasma levels will be lower, masking the effect of the SLC47A1 efflux polymorphism.Also Tkáč et al. identified in 148 incident metformin users that the rs2289669 polymorphism is associated with HbA1c reduction. The homozygous carriers of the minor A allele had twofold reduction in HbA1c in comparison with the G-allele carriers (1.10 ± 0.18% versus 0.55 ± 0.09%) . Stockerg effect . In a sug effect . Most liSLC47A2 gene, is expressed at the brush border membrane of the kidney. This transporter has two functional isoforms, MATE2 and MATE2-K. The g.−130G>A polymorphism is situated in the basal promoter region of MATE2-K and results in an increase in promoter activity. In the study by Choi et al., this polymorphism was associated with the HbA1c lowering effect in 248 incident metformin users [SLC47A1 gene. Both MATE1 and MATE2 are coexpressed at the apical membrane of the kidney, possibly explaining their mutual effect [Also the MATE2 transporter, encoded by the in users . In the in users . The effl effect .γ). Activation of this receptor regulates the transcription of hundreds of genes, involved in lipid and glucose metabolism. Effects associated with PPAR-γ activation include decreased insulin resistance, decreased leptin levels, and increased adiponectin levels. Troglitazone has been withdrawn from the market worldwide due to liver injury and rosiglitazone has been withdrawn from the market in Europe due to an increased risk of cardiovascular events and put under restrictions in the USA.The group of thiazolidinediones, including troglitazone, pioglitazone, and rosiglitazone, were introduced in the late 1990s. These drugs are agonists of the peroxisome proliferator-activated receptor , the association between CYP2C8*3 variant and change HbA1c was studied. The authors found reduced therapeutic response and a lower risk for developing edemas in CYP2C8*3 carriers. In this study rosiglitazone was added to the previous insulin treatment and it was allowed to change the insulin dose during the treatment which could have influenced the observed study results [Both pioglitazone and rosiglitazone are metabolized by the cytochrome P450 2C8 isoenzyme. The a levels –64 and oa levels . All fou results . γPPAR- gene. One polymorphism in this gene, the P12A polymorphism (rs1801282), was identified in 1997 and studied extensively in the relation to the incidence of type 2 diabetes mellitus [The obvious first choice in the pharmacogenetic research after thiazolidinediones was the mellitus . In a memellitus . Three smellitus , 69. On mellitus . Blüher mellitus , 72. Wheγ coactivator-1α (PGC-1α) is a regulator of PPAR-γ, and it is associated with the risk of developing diabetes. Both the T394T and the G482S variants in this gene were related to response to rosiglitazone therapy in the study by Kang et al. in 241 patients [The proliferator-activated receptor-patients . But in patients .γ regulates numerous other genes, and some of these genes have been subject of pharmacogenetic research. Adiponectin is the best studied gene that is regulated by PPAR-γ. Three polymorphisms in this gene, − 11377C>G, +45T>G, and +276G>T, were previously associated with obesity development and the incidence of type 2 diabetes mellitus, and the effect of these polymorphisms on thiazolidinedione response was studied. In the study by Eun et al., the +45T>G and +276G>T polymorphisms were associated with the change in HbA1c levels in 166 rosiglitazone users [The binding of thiazolidinediones to PPAR-ne users . The assne users . In the ne users . β-cells after ingestion of glucose or mixed meals by intestinal hormones glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) [GLP1R) variants were associated with altered β-cell sensitivity to GLP-1 infusion [GIPR) locus was reported to influence the responses of the glucose and insulin to an oral glucose challenge in a meta-analysis of nine GWAS which included 15,234 nondiabetic subjects [The incretin effect is mediated by stimulation of insulin secretion from pancreatic de (GIP) . In a piinfusion . Variatisubjects . TCF7L2 [KCNQ1) [WFS1) [ Besides the gene variants encoding GLP-1 and GIP receptors, several T2D related gene variants were reported to be associated with the incretin effect. Gene variants in TCF7L2 –81, volt [KCNQ1) , and wol) [WFS1)  were ass) [WFS1) . Since endogenous and exogenously applied GLP-1 is rapidly degraded by dipeptidylpeptidase-4, two pharmacologic approaches were developed to bypass this limitation and to enhance the incretin effect: GLP-1 receptor antagonists are resistant to DPP-4 and applied subcutaneously. Another possibility is to inhibit DPP-4 by orally applied DPP-4 inhibitors (gliptins) .TMEM114, CHST3, and CTRB1/2) had large effects on GLP-1 stimulated insulin secretion during hyperinsulinemic clamp [CTRB1/2 gene encoding chymotrypsinogen and the response to gliptin treatment. 10% patients carrying the minor G-allele showed a significantly smaller decrease in HbA1c (in average by 0.5%) in comparison to TT homozygotes [Until recently, no pharmacogenetic study with incretin mimetics was published. In their recently published study, ‘t Haart et al. used Metabochip  and showed that three genetic loci (ic clamp . A pharmozygotes .There are a few areas where genetics is used to guide therapy. This is becoming mainstream in the field of cancer therapy where somatic mutations can determine the choice of treatment. Out with the cancer setting, there are currently limited examples of clinical utility of genetics, with probably the most accepted use being HLA genotyping prior to commencing the antiretroviral, abacavir. The use of genotyping abolishes hypersensitivity reactions to the drug . Diabete


Failure of apoptosis is one of the hallmarks of cancer. As an execution-phase caspase, caspase-9 plays a crucial role during apoptosis. To examine whether the Ex5+32 G>A (rs1052576) polymorphism in the CASP-9 gene alters cancer risk, we conducted a comprehensive meta-analysis of 7 case-control studies consisting of a total of 1668 cancer cases and 2294 healthy controls. All studies considered, A allele and A allele carriers of Ex5+32 G>A in the CASP-9 gene had significant associations with cancer risk . In the subgroup analysis, we found that the A allele of Ex5+32 G>A was a protective factor for cancer risk in Chinese and American populations . Similarly, we also found positive associations between A allele carriers of Ex5+32 G>A and cancer risk in Chinese and American populations . In addition, we identified that A allele and A allele carriers of Ex5+32 G>A may decrease the risk of cancer in the Asian population . In conclusion, this meta-analysis demonstrated that A allele and A allele carriers of the Ex5+32 G>A polymorphism in the CASP-9 gene may be protective factors for cancer risk. Apoptosis is an essential mechanism to eliminate unwanted cells during the development and homeostasis of multi cellular organisms ,2. An imet al family of proteins. It has been shown to be an executioner protein of apoptosis. Caspase-9 plays a central role in the execution-phase of cell apoptosis. Single nucleotide polymorphisms (SNPs) are the most common form of human genetic variation and may contribute to an individual’s susceptibility to cancer . In receet al found thWe performed an electronic search of the PubMed, Cochrane library, Embase, Web of Science, SpringerLink, CNKI and CBM databases extensively to identify relevant studies available up to May 1, 2012. The search terms included [‘caspase-9’ or ‘CASP-9’ or ‘caspase-9’ (Mesh)] and  and [‘cancer’ or ‘tumor’ or ‘neoplasms’ (Mesh)]. References in the eligible studies or textbooks were also reviewed through a manual search to identify other potentially eligible studies.The included studies were required to meet the following criteria: i) case-control studies focusing on associations between the CASP-9 Ex5+32 polymorphism and cancer risk; ii) all patients were diagnosed with malignant tumors confirmed by pathological examination of the surgical specimen; iii) the frequencies of alleles or genotypes in case and control groups could be extracted; iv) the publication was in English or Chinese. Studies were excluded when they were: i) not case-control studies concerning CASP-9 Ex5+32 polymorphism and cancer risk; ii) based on incomplete data; iii) irrelevant or overlapping data were reported; iv) meta-analyses, letters, reviews or editorial articles.Using a standardized form, data from published studies were extracted independently by two reviewers (S. Yan and Y.-Z. Li) to populate the necessary information. The following information was extracted from each of the articles: first author, year of publication, country, language, ethnicity, study design, source of cases and controls, number of cases and controls, mean age, sample, cancer type, genotype method, allele and genotype frequency, and evidence of Hardy-Weinberg equilibrium (HWE) in controls. In case of conflicting evaluations, an agreement was reached following a discussion with a third reviewer (Y.-L. Liu).Two reviewers (S. Yan and Y.-Z. Li) independently assessed the quality of papers according to modified STROBE quality score systems ,11. Forthttp://ims.cochrane.org/revman/download) and STATA Version 12.0  softwares. Between-study variations and heterogeneities were estimated using Cochran’s Q-statistic  or I2>50% indicated that heterogeneity among studies existed, the random effects model was conducted for meta-analysis. Otherwise, the fixed effects model was used. To establish the effect of heterogeneity on the conclusions of the meta-analyses, subgroup analysis was carried out. We tested whether genotype frequencies of controls were in HWE using the χ2 test. Funnel plots are often used to detect publication bias. However, due to limitations caused by varied sample sizes and subjective reviews, Egger’s linear regression test which measures funnel plot asymmetry using a natural logarithm scale of OR was used to evaluate the publication bias (The odds ratio (OR) and 95% confidence interval (95% CI) were calculated using Review Manager Version 5.1.6 (provided by the Cochrane Collaboration, available at: tatistic  (P≤0.05 ion bias . When thAccording to the inclusion criteria, seven studies ,9,15–19 A summary of the findings of the meta-analysis of the association between CASP-9 Ex5+32 G>A polymorphism and cancer risk is provided in Publication bias of the literature was assessed by Begger’s funnel plot and Egger’s linear regression test. Egger’s linear regression test was used to measure the asymmetry of the funnel plot. All graphical funnel plots of the included studies appeared to be symmetrical . Egger’sApoptosis is a particular type of programmed cell death which commonly occurs in the developing embryo, in normal healthy adult tissues and in many pathological settings . The moret al(Caspase-9 is a key regulator of apoptosis or programmed cell death, an essential defense mechanism against hyper-proliferation and malignancy. Polymorphic variation in the CASP-9 gene has been reported to influence cancer risk, especially in the Ex5+32 variant. The published studies of an association between the CASP-9 Ex5+32 variant and different cancers have generated inconsistent results. Lou et al reportedet al. This coSimilar to other meta-analyses, a number of limitations of this study should be addressed. First, the relevant research articles are not many and the sample size of this meta-analysis was not large. In addition, some relevant studies could not be included in our analysis due to incomplete raw data. Thirdly, we were not able to address the sources of heterogeneity among all studies. Fourthly, although all cases and controls of each study were well defined with similar inclusion criteria, there may be potential factors that were not taken into account that may have influenced our results. Most important of all, our meta-analysis was based on unadjusted OR estimates since not all published presented adjusted ORs or when they did, the ORs were not adjusted by the same potential confounders, such as ethnicity, gender and geographic distribution. Given these results, additional investigation in these areas is needed, and our conclusions should be interpreted cautiously.In conclusion, this meta-analysis of seven case-control studies demonstrated that the CASP-9 Ex5+32 G>A polymorphism is involved in the pathogenesis of variant cancer. The A allele, A allele carrier and AA genotype of Ex5+32 G>A polymorphism may be protective factors for cancer risk. As few studies are available in this field current evidence remains limited. Therefore, it is necessary to conduct large studies with adequate methodological quality, properly controlling confounds in order to obtain valid results.


Modification of lifestyle habits is a key preventive strategy for many diseases. The role of lifestyle for the onset of headache in general and for specific headache types, such as migraine and tension-type headache (TTH), has been discussed for many years. Most results, however, were inconsistent and data on the association between lifestyle factors and probable headache forms are completely lacking. We evaluated the cross-sectional association between different lifestyle factors and headache subtypes using data from three different German cohorts. Information was assessed by standardized face-to-face interviews. Lifestyle factors included alcohol consumption, smoking status, physical activity and body mass index. According to the 2004 diagnostic criteria, we distinguished the following headache types: migraine, TTH and their probable forms. Regional variations of lifestyle factors were observed. In the age- and gender-adjusted logistic regression models, none of the lifestyle factors was statistically significant associated with migraine, TTH, and their probable headache forms. In addition, we found no association between headache subtypes and the health index representing the sum of individual lifestyle factors. The lifestyle factors such as alcohol consumption, smoking, physical activity and overweight seem to be unrelated to migraine and TTH prevalence. For a judgement on their role in the onset of new or first attacks of migraine or TTH (incident cases), prospective cohort studies are required.The online version of this article (doi:10.1007/s10194-010-0286-0) contains supplementary material, which is available to authorized users. Primary headache disorders, including migraine and tension-type headache (TTH), affect millions of people worldwide . The burThis analysis is part of the German DMKG Headache Study. To evaluate the association between lifestyle factors and headache, we used data from three studies which were conducted in different regions of Germany: the Study of Health in Pomerania (SHIP) in the northeast of Germany, Cooperative Health Research in the Region of Augsburg (KORA) in the south of Germany and the Dortmund Health Study (DHS) in the west of the country. These regions had been selected for the German DMKG Headache Study with the aim to assess prevalences and consequences of headache types in different areas of Germany .SHIP  is a popThe headache question module was implemented in the first follow-up after 5 years on average. Follow-up response was 83.6%, yielding 3,300 participants aged 25–88 years for this analysis.KORA  is a regn = 1,312) since headache classification according to the IHS criteria required the extended headache information assessed by the personal interview.For the DHS, a total sample of 3,820 persons aged 25–75 years was randomly selected from the Dortmund city registration office out of a total population of 591,000 and contacted by mail. Of those sampled, 395 persons were excluded because they had moved out of the study area, died or had no sufficient knowledge of the German language. 3,425 persons were eligible and invited to participate in a personal interview at the study centre. If personal participation at the study centre was impossible, a questionnaire with a subset of the otherwise identical questions was mailed to the participants. The overall response rate was 66.9%, yielding 2,291 participants. For the purpose of this analysis, we only used the data of participants attending the personal interview at the study centre  was then calculated using the beverage-specific quantity–frequency measure: number of days with alcohol consumption  multiplied by the average daily alcohol consumption over the past week (KORA/DHS) or month (SHIP), respectively. The method used for estimating the mean daily alcohol consumption is an established and validated method implemented in the WHO MONICA project . Gender-2. Finally, we summarized the four life style factors in one individual health score by adapting a previously proposed health index [2 and physical activity of more than 2 h/week. The three data sets provided additional information on baseline characteristics including age, sociodemographic data, and cardiovascular disease risk factors.For physical activity, the ascertainment differed between the three studies. In the DHS, physical activity in hours per week was assessed by one question. In KORA, physical activity was distinguished in exercise during summer and exercise during winter. Based upon this information, we have averaged the total amount of physical activity in hours per week over the year. In SHIP, the type of physical activity was also assessed. To achieve comparability in these cases, we distinguished three categories representing the amount of physical activity per week: no physical activity, ≤2 h/week, >2 h/week. Since the participants’ interviews were distributed over a period of three full years in SHIP and 1 year in the DHS, at least one full year of data assessment is covered which facilitate comparability to the averaged amount of physical activity in KORA. Smoking status was divided into the following categories: non-smokers, ex-smokers and current smokers. The category current smokers included participants who smoked on a regular and irregular basis. Height and weight were measured in all three studies following the original MONICA protocol for BMI measurement and the BMI was subsequently derived. The following BMI categories were defined: <25, 25.0–29.9 and ≥30 kg/mth index . This sc2), smoking status , gender-specific alcohol consumption  and physical activity . Participants with no history of the specific headache type and the respective lifestyle factor were chosen as reference group. Logistic regression models were adjusted for age (continuous) and sex. Additional adjustment for other lifestyle factors and cardiovascular disease risk factors did not indicate different associations. We further calculated age- and sex-adjusted logistic regression models with the health score as independent and every headache type as dependent variable. Participants with missing values for either the exposure or outcome variable were excluded from the corresponding analysis.To provide comparability between the three data sets, we restricted our analyses to the age groups 35–75 years as previously done . We usedp value of < 0.05 was considered statistically significant.For all analyses, we used STATA . A two-tailed A total of 7,417 individuals participated in the three studies; 2,805 in KORA, 3,300 in SHIP and 1,312 in the DHS.Baseline characteristics of participants according to the three different study regions are summarized in Table We found regional variations concerning lifestyle habits and common chronic diseases. In KORA, participants were less likely to have a history of hypertension, diabetes, stroke or cancer compared to participants in SHIP or in the DHS. In contrast, the 6-month prevalence for any headache (54.55%) and for TTH was higher in KORA compared to the other study regions Table .In Tables Increased alcohol consumption tended to be associated with a decreased risk of experiencing migraine and probable TTH, but without statistically significant results in all of the three studies Tables , 3, 5. WThe association between the health index and headache is summarized in tables Tables In this cross-sectional analysis of data from three different studies in Germany, we found two noteworthy results. First of all, we found considerable variations in the distribution of lifestyle factors between the three regions. Second, there was no consistent association between migraine or TTH and the lifestyle factors smoking, alcohol consumption, physical activity and BMI irrespective of the prevalence of a specific lifestyle factor in one of the regions. In addition, a health index reflecting a sum score of four lifestyle factors was not associated with headache subtypes.Several studies have evaluated a possible association between single lifestyle factors and headache with mostly conflicting results. A negative influence of alcohol consumption on headache occurrence, in general, and headache subtypes have been discussed for years with inconsistent findings. Several cross-sectional studies found no association between alcohol consumption and headache prevalence , 13 as wInconsistency in published results also exists with regard to a possible relation between smoking and headache subtypes , 27–31. The association between physical activity and headache has gained popularity since case reports and small clinical-based studies suggested that physical activity may reduce headache severity, frequency and activity , 32, 33.Some studies suggested an association between obesity, a consequence of lifestyle, and headache –38. WithA possible association between lifestyle factors and headache would have considerable consequences for the prevention of headache. By modifying their individual lifestyle habits, headache sufferers would have the opportunity to influence the occurrence, frequency and severity of headache. As presented before, the results of studies investigating the association between lifestyle factors and headache are not consistent. Methodological differences in the assessment of lifestyle factors and the headache case definition may be one cause for the observed inconsistency. The majority of studies including our own are cross-sectional studies. No assumptions regarding a causal relationship or a time sequence between lifestyle variables and headache are possible in this design. Thus, if, e.g., some headache patients report specific life style behaviours, especially alcohol consumption, to be trigger factors for their headache, they avoid the exposure. Also, patients with severe and frequent headache might not have the ability to exercise on a regular basis . A prospOur study has several strengths including the large sample size, inclusion of participants from three different regions within one country and a standardized headache assessment by face-to-face interviews. In addition, we classified migraine and TTH and their probable forms using the diagnostic criteria of the 2004 edition of the IHS. Furthermore, information on a variety of lifestyle factors and cardiovascular disease risk factors was available. Several limitations should also be considered when interpreting our results. First, the information on lifestyle variables and headache symptoms is self-reported and we can not rule out potential underreporting, e.g. in alcohol consumption and smoking. Second, assessment of 2 lifestyle variables, physical activity and alcohol consumption, varied slightly between the three studies and we had to transform the information into uniform categories. However, evaluating the association with the original variables in each study yielded no different results (data not presented). Third, we had to exclude over 200 participants in SHIP due to missing data on the exposure status, mainly alcohol consumption. Therefore, we cannot rule out potential selection bias for this part of the analysis. Fourth, among headache sufferers, a higher percentage of participants in SHIP have been diagnosed with probable migraine and probable TTH compared to the DHS and KORA. Since the data collection and headache classification was completely standardized with trained interviewers across all studies, this is unlikely to be due to selection or recall bias. A potential explanation might be a difference in the perception of headache, including the questions from the headache module, in the north-eastern population compared to the two other studies. Fifth, because of the cross-sectional design of our study, a statement concerning a causal relationship or the time sequence of an association cannot be done. Sixth, the cohorts consisted of participants aged 35–75 years from three different regions in Germany which may limit the generalizability of our results to other populations. Lastly, headache is highly prevalent among subjects aged 18–35 years. Since we could not include subjects in this age range, our presented headache prevalence is lower compared to other studies assessing headache prevalence. However, we do not believe that the association between headache and lifestyle depends on headache prevalence and our population is suitable for studying the relationship between lifestyle factors and headache.In summary, in this large study, we found variations in lifestyle factors in three regions in Germany, but no associations between single or combined life style factors and headache types were observed. Future research should focus on the association of lifestyle habits with first or recurrent headaches.Supplementary material 1 (DOC 42 kb)Below is the link to the electronic supplementary material.