To explore the relationship between chronic kidney disease (CKD) and diabetic retinopathy (DR) in a representative population of type 2 diabetes mellitus (DM2) patients in Catalonia (Spain).2 and/or urine albumin to creatinine ratio (UACR) ≥30 mg/g. DR was categorized as non-vision threatening diabetic retinopathy and vision threatening diabetic retinopathy.This was a population-based, cross-sectional study. A total of 28,344 patients diagnosed with DM2 who had recorded ophthalmologic and renal functional examinations were evaluated. Data were obtained from a primary healthcare electronic database of medical records. CKD was defined as an estimated glomerular filtration ratio (eGFR) of <60 ml/min/1.73m2 [OR], 95% confidence interval [CI], 1.3 (1.1–1.6).CKD was associated with a higher rate of DR [OR], 95% confidence interval [CI], 1.5 (1.4–1.7). When we analyzed the association between different levels of UACR and DR prevalence observed that DR prevalence rose with the increase of UACR levels, and this association was significant from UACR values ≥10 mg/g, and increased considerably with UACR values ≥300mg/g . This association was lower in patients with eGFR levels 44 to 30 mL/min/1.73mThese results show that CKD, high UACR and/or low eGFR, appear to be associated with DR in this DM2 population. Chronic kidney disease (CKD) and diabetes retinopathy (DR) are two major microvascular complications found in long-standing type 1 (DM1) and type 2 diabetic (DM2) patients. In addition to sharing risk factors, such as poor glycaemia control and systolic hypertension, CKD and DR are reflected in the clinical manifestations of similar microvascular lesions in the glomerular and retinal vessels . UACR anUrine albumin to creatinine ratio (UACR) and low estimated glomerular filtration rate (eGFR) are clinical markers of renal function. CKD is often associated with DR in DM1 , 5, and High UACR is a marker of endothelial dysfunction and may influence the microvasculature of the kidney and retina. However some studies –10 foundThe aim of this study was to investigate the association between CKD, UACR and/or eGFR, and DR in a representative Catalonian (Spain) DM2 population.A population-based, cross-sectional study was performed in Catalonia (Spain) with patients aged between 30 and 90 years , diagnosed with DM2 prior to retinal photography screening, and whose DR category was recorded in their medical records. The most recent retinal photography registered was selected and employed as the index date. The criteria for the diagnosis of type DM2 were those established by the American Diabetes Association  at the tData were obtained from the SIDIAP (System for Research and Development in Primary Care) electronic database. The SIDIAP includes data from the primary healthcare electronic medical records (e-CAP) on demographic information, appointment dates with doctors and nurses, clinical diagnoses, clinical variables, prescriptions written, referrals to specialists and hospitals, results from laboratory tests, and medication sold by pharmacies. The quality of the SIDIAP data has been previously documented, and the database has been widely used to study the epidemiology of a number of health outcomes , 17.2.Serum creatinine levels and UACR were determined. CKD was defined as UACR >30 mg/g and/or eGFR <60 mL/min/1.73mNormoalbuminuria was defined as UACR <30 mg/g; microalbuminuria as UACR 30–299 mg/g; and macroalbuminuria as UACR ≥300 mg/g. The Chronic Kidney Disease Epidemiology Collaboration equation was employed to measure eGFR .In a large, community-based screening programmer, such as that employed in our study, fundus photography is considered to be the preferred option . PhotogrThe following data were obtained from each patient: age, age at diagnosis of diabetes, duration of diabetes, gender, and glycated hemoglobin levels (A1C). Cardiovascular risk factors including body mass index (BMI), total cholesterol, low-density (LDL) cholesterol, high density lipoprotein (HDL) cholesterol, non-HDL cholesterol, systolic and diastolic blood pressure (SBP and DBP), pulse pressure (PP), and smoking status according to the last condition registered before the index date were collected. Data for clinical variables were gathered from the 15 months prior to the index date with the exception of blood pressure, PP, and BMI, which were obtained from the previous 12 months. Additional data were gathered on medication.The study was approved by the Ethics Committee of the Primary Health Care University Research Institute Jordi Gol (protocol number 13/137). All patient records and information was anonymized and de-identified prior to analysis.A descriptive analysis stratified by renal function (according to eGFR and UACR) and retinography result was performed. The absolute and relative frequencies of the qualitative variables, and their mean and standard deviation (or median and interquartile range according to the characteristics of the variable) were calculated.In order to study whether the clinical variables of interest depended on renal function, Pearson’s chi square test and analysis of variance (ANOVA) were employed for means and proportions, respectively. The hypothesis contrast was bilateral in all cases with a 0.05 level of significance.In addition, the relationship between renal function values (according to eGFR and UACR) and the presence of retinopathy was assessed by logistic regression models adjusted by age, sex, age at retinography, duration of DM2, systolic blood pressure, A1C ≤7%, smoking, BMI, and cardiovascular disease.Analyses were performed with Stata/SE version 13 for Windows .2, women had lower rates than men (p<0.001). As can be observed in Table 1, diabetes duration, hypertension, cardiovascular disease (CVD), and treatment with insulin displayed a direct association with decreased eGFR.Prior to retinography 28,344 DM2 patients had their eGFR and UACR values registered. From the total sample, 14.6% had an eGFR <60 mL/min/1.73mTable 2), 16.0% were ≥30 mg/g with higher levels being found in men (p<0.001). DM2 duration, poor glycemic control , SBP, increased heart rate, hypertension, CVD, and treatment with insulin showed a direct relationship with an increase in UACR levels. An inverse relationship, however, was observed between UACR and plasma hemoglobin levels.In contrast, an inverse relationship between eGFR and non-HDL cholesterol, plasma hemoglobin, heart rate, and DBP was reported. With respect to UACR values . Patients with elevated UACR had higher rates of DR, particularly if UACR values were ≥300 mg/g ; this rate was lower in patients with eGFR levels 44 to 30 mL/min/1.73m2 . Patients with UACR values 30 to 299 mg/gr had DR rate slightly higher than those with eGFR values of 30 to 44 mL/min/1.73m2 . When we analyzed the association between different levels of UACR and DR prevalence  we observed that DR prevalence rose with the increase of UACR levels, and this association was significant from UACR values 10 to 29 mg/g, , and increased considerably with UACR values ≥300 mg/g .S1 Table. Moreover, Fig 2 shows the association between CKD and DR severity. Patients with eGFR <60 mL/min/1.73m2 and UACR <30 mg/g had an increased non-VTDR rate  and a non-significant increase in VTDR . In individuals with UACR ≥30 mg/g and eGFR ≥60 mL/min/1.73m2 the rate of VTDR  was higher than non-VTDR .The prevalence of DR using the KDIGO combination of UACR and eGFR categories is shown in 2 were associated with higher DR prevalence, but we did not find this association with eGFR levels ≥45/ml/min/1.73 m2. This association was not significant with eGFR levels <30 mL/min/1.73m2, probably because there were few patients in this group.Our study showed that high UACR level significantly increases the prevalence of diabetic retinopathy in type 2 diabetic patients, even after adjustment for variables, and this association was significant from UACR values ≥10 mg/g. These findings concur with the RIACE study cohort . We obsePenno et al.  reportedCKD in DM2 is more heterogeneous than in type 1 diabetes, retinopathy and albuminuria were both absent in 30% of adults with DM2 and chronic renal insufficiency according to the Third National Health and Nutrition Survey . PatientRecently, Lee et al.  showed aOur study should be interpreted with consideration of the following limitations. First, this study was a cross-sectional analysis; therefore, the data were recorded from an electronic database and diabetic patients with DR-VTDR, who were attended by an ophthalmologist or endocrinologist, could have been poorly represented. Second, because of the small number of cases in some categories, we could not carry out the final analysis using all KDIGO categories. Despite these limitations, this study used a nationally representative sample of DM2 patients. Moreover, to the best of our knowledge, this is the first large population based study to examine the association between CKD, decreased eGFR and high UACR, and DR among a representative Catalonian, Spain, DM2 population.CKD appears to be associated with DR in this DM2 population. Elevated UACR had a greater association with DR prevalence than decreased eGFR, but both were associated with DR in DM2 patients.S1 Table(DOCX)Click here for additional data file.


To compare the performance of iohexol plasma clearance and creatinine-based renal function estimating equations in monitoring longitudinal renal function changes in chronic heart failure (CHF) patients, and to assess the effects of body composition on the equation performance.Iohexol plasma clearance was measured in 43 CHF patients at baseline and after at least 6 months. Simultaneously, renal function was estimated with five creatinine-based equations  and body composition was assessed using bioimpedance and dual-energy x-ray absorptiometry.2], P = 0.001). This decline was significantly higher in patients receiving mineralocorticoid receptor antagonists at baseline . Mean serum creatinine concentration did not change significantly during follow-up and no creatinine-based renal function estimating equation was able to detect the significant longitudinal decline of renal function determined by iohexol clearance. After accounting for body composition, the accuracy of the equations improved, but not their ability to detect renal function decline.Over a median follow-up of 7.5 months (range 6-17 months), iohexol clearance significantly declined (52.8 vs 44.4 mL/[min ×1.73 mRenal function measured with iohexol plasma clearance showed relevant decline in CHF patients, particularly in those treated with mineralocorticoid receptor antagonists. None of the equations for renal function estimation was able to detect these changes.NCT01829880 Renal function is one of the key clinical parameters to be monitored in heart failure patients; it predicts mortality and can be crucial for making therapeutic decisions ,2. The “Accuracy of equations based on serum creatinine concentration is affected by different demographic variables. Serum creatinine concentration depends on renal function but is also associated with muscle mass, ie, body composition . GeneralA significant proportion of CHF patients with systolic dysfunction develop a rapid decline in renal function, regardless of their baseline renal function. Among all patients with heart failure, the prevalence of some degree of chronic kidney disease is between 25% and 63% ,16. In tWe aimed to compare the performance of iohexol plasma clearance and creatinine-based glomerular filtration estimating equations  in 6-month renal function estimation in CHF patients. We also investigated the association of estimates with body composition evaluated using bioimpedance analysis (BIA) and dual-energy x-ray absorptiometry (DEXA).2) at baseline visit to maintain iohexol sampling interval of 4 hours (Consecutive patients with CHF diagnosed according to European Society of Cardiology guidelines attending our outpatient clinic were screened for inclusion between November 2011 and February 2013. We excluded patients who had estimated glomerular filtration rate (eGFR) with MDRD4 < 30 mL/  was administered by intravenous injection. Blood samples were drawn into lithium heparinized tubes before administration of iohexol 3 hours and 4 hours post administration. Blood was centrifuged immediately  and plasma was stored at -80°C for further analyses. The samples were analyzed on a continuous basis  throughout the study. Plasma concentration of iohexol was measured as described later in the text. Clearance of iohexol was calculated based on a one-compartment model utilizing measured 3-hour and 4-hour iohexol concentrations and applying Bröchner-Mortensen correction .Blood biomarkers  were determined in a blood sample drawn before administration of iohexol. Serum creatinine concentration was measured by the kinetic Jaffe reaction, rate-blanked and compensated on a Cobas 6000 analyzer . The method is standardized to Isotope Dilution Mass Spectrometry method.eGFR was calculated on the basis of serum creatinine concentration and other variables using the following five equations: CG, CG adjusted for lean body mass (GCLBM), MDRD4, MDRD6, and CKD-EPI equation . CreatinCr is serum creatinine concentration (in μmol/L). eGFR was calculated in mL/ (min ×1.73 m2) for all five equations. To transform the units of CG and CGLBM equations from mL/min to mL/(min ×1.73 m2), body surface area was calculated using the DuBois equation . Fat mass (in kg and %), lean mass (in kg and %), dry lean mass (in kg and %), and water content (in liters and %) was recorded. Four patients with pacemakers did not undergo this test.Full body scan DEXA was performed with Hologic Explorer, QDR Series  to assess fat mass (in kg and %), lean mass (in kg and %), and bone mineral content (in kg). The sum of lean mass in both arms and legs was calculated to obtain appendicular skeletal muscle mass, and skeletal muscle index was calculated with Equation 2 . Fat-freWhere SMI is skeletal muscle index and ASM is appendicular skeletal muscle mass.Where FFMI is fat-free mass index and FFM is fat-free mass.Plasma concentration of iohexol was measured with an isocratic reversed-phase high-performance liquid chromatography coupled with an UV detector. The method, which was previously described , was intP values lower than 0.05 were considered statistically significant. Kolmogorov-Smirnov test showed a normal distribution of all values included in linear regression and/or paired sample t tests (P > 0.05). All calculations were performed with SPSS for Windows 19.0 .Data are presented with a mean value ± standard deviation or median and range. Two tailed t test was used to compare mGFR and patients' parameters at both visits, and an independent sample t test was used to compare the influence of different categorical variables on mGFR. In cases of linear regression with multiple comparisons employed on the same data set, Bonferroni correction was used. The paired sample t test with multiple comparisons was done in SPSS and P values were adjusted for Bonferroni correction.Linear regression was used to determine the extent of linear dependence between numerical patients' characteristics and mGFR and changes in mGFR (Pearson correlation). Paired sample Absolute differences between eGFR and mGFR were calculated with Equation 4 and PE with Equation 5.Where eGFR is estimated glomerular filtration rate, mGFR is measured glomerular filtration rate, and PE is percentage error.2), percentage of estimated GFR within 30% of measured GFR (P30), and correlation coefficients were calculated for all equations at both visits. Bland-Altman plots were drawn for all equations at baseline. Linear regression was used to evaluate PE of equations with both mGFR and parameters of body composition at baseline. Additionally, multiple linear regression was performed to assess whether equations with included percentage lean body mass (measured with DEXA at baseline visit) better predicted mGFR . Percentage lean body mass was chosen to be included into the model on the basis of results of Pearson correlation between various body composition parameters and mGFR.Mean PE, absolute difference in mL/(min ×1.73 m2), and 2 patients were additionally excluded from the analysis due to inappropriate iohexol administration. Accordingly, 43 patients with CHF  were included into the study, and 31 patients had a follow-up iohexol assessment  (2), with mGFR below 30 mL/(min ×1.73 m2) in 2 (5%) patients, between 30 and 60 mL/(min ×1.73 m2) in 26 (61%) patients, and over 60 mL/(min ×1.73 m2) in 15 (35%) patients.49 patients were screened for inclusion. 2 patients did not consent to take part in the investigation, 1 patient reported a history of severe allergic reactions to drugs, 1 patient had an eGFR below 30 mL/(min ×1.73 mtration) . The meaP = 0.002). Among concomitant diseases and drug therapy, only arterial hypertension was associated with poorer renal function . Different parameters of body composition were correlated with baseline mGFR: fat mass in kg , percentage fat mass , and percentage lean mass .At baseline, mGFR was inversely correlated with age  to 30-60 mL/(min ×1.73 m2) and in additional 6 patients from 30-60 mL/(min ×1.73 m2) to <30 mL/(min ×1.73 m2).Serum biomarkers did not significantly change between the two visits, except for serum albumin . Body weThe mean PE and absolute differences between eGFR and mGFR tended to increase toward positive values from baseline to follow-up visit . CKD-EPIThe accuracy of CG, CGLBM, and CKD-EPI equations was associated with body composition parameters, while the accuracy of MDRD4 and MDRD6 was not (Supplementary Table 1 2) in 26% of patients and did not decline in 26% of patients (2) in only 3%-6% of patients and did not decline in 45%-52% of patients.Between the two visits, mGFR declined for more than 15 mL/(min ×1.73 mpatients . eGFR deP < 0.050).The decline in mGFR was not related to any baseline characteristic with the exception of mineralocorticoid receptor antagonists (spironolactone or eplerenone) prescription at baseline . PatientP = 0.032), body surface area , systolic blood pressure , serum urea concentration , and serum creatinine concentration .The percentage change in mGFR was correlated with changes in demographic parameters and parameters of body composition between both visits. A significant correlation was observed between change in body weight  at follow-up. Similar absolute overestimation (10 to 15 mL/[min ×1.73 m2]) was observed in the study by O’Meara et al (2]) was comparable to the mean mGFR in our patients at follow-up (44.6 mL/[min ×1.73 m2]). Two other studies in heart failure patients found that equations underestimated mGFR, but these were performed in populations with mean GFR higher than 70 mL/(min ×1.73 m2)  ,29. CGLBThe accuracy of CG, CGLBM, and CKD-EPI equation was related to body composition parameters and could be partly improved by inclusion of lean mass into the calculation. In patients with a lower percentage of lean mass there was a greater risk of renal function overestimation, while in patients with a higher percentage of lean mass there was a greater risk of its underestimation. This could be due to the relationship among lean mass, muscle mass, and serum creatinine concentration. In extremely underweight or obese patients, estimation of renal function with CG and CKD-EPI equations could lead to greater prediction errors, which can be partly improved by body composition measurement.We were not able to explain equations’ failure to detect renal function decline with changes in body composition. Moreover, MDRD equations, which do not include body composition parameters, also followed the same trend. The reasons for failure are likely to be complex and multifactorial. Previous studies have already shown that equations perform poorly for longitudinal monitoring of renal function because of increased fraction of creatinine tubular secretion in the failing kidney ,31. Furt2), although this is not a recommended approach. However, we aimed to use the same approach for all equations in order to estimate which equation is best for CHF patients regardless of their kidney function. The influence of body composition on the accuracy of GFR estimation was studied in both sexes, not taking into consideration the body composition differences between the sexes. Renal function declined during follow-up, but the same protocol for renal function measurement with iohexol was applied at both visits. For patients with GFR<30 mL/(min ×1.73 m2), this could be relevant as iohexol clearance is expected to overestimate renal function with sampling times shorter than 4 hours. However, this was clearly demonstrated only for one-sample protocol (This study has several limitations. With a study sample of 31 patients who took part in the follow-up, generalizibility of results is limited and confirmatory studies are needed. However, the observed renal function decline was consistent over the entire patient group and was clinically significant. The GFR was estimated at a single point in time at baseline and follow-up and may thus not completely reflect dynamic longitudinal changes of kidney function. Additionally, the MDRD equations were also applied in patients with GFR over 60 mL/(min ×1.73mprotocol , while wIn conclusion, mGFR outperformed the equations in CHF patients, and did so across all stages of chronic kidney disease. Patients receiving mineralocorticoid receptor antagonists were more prone to develop a rapid decline in renal function. All tested equations correlated well with mGFR, but their overestimation increased as mGFR decreased. Due to their dependence on body composition parameters, CG and CKD-EPI equations should be used with caution in extremely underweight or obese patients. In clinical practice, eGFR appears to be insufficient to detect clinically relevant changes in renal function, which is why pharmacological therapy may be delayed or not modified, exposing some of the patients to increased risk of complications. However, eGFR cannot be replaced by an exogenous marker of renal function, but rather with a different endogenous marker. Our results also imply that eGFR may not be an ideal primary end-point in patients with CHF. Further studies with larger sample size and longer follow-up are needed to clarify this issue.


P<0.01), the peak height of the first Gaussian significantly decreased (P<0.01) and the peak height of the second Gaussian significantly increased (P<0.01), inducing the significantly decreased peak position interval and significantly increased peak height ratio (both P<0.01). Sex factor had no significant effect on all evaluation indices . Moreover, the interaction between sex and blood pressure factors also had no significant effect on all evaluation indices . These results showed that blood pressure has significant effect on the change of wave reflection when using the recently developed Gaussian fitting method, whereas sex has no significant effect. The results also suggested that the Gaussian fitting method could be used as a new approach for assessing the arterial wave reflection.An early return of the reflected component in the arterial pulse has been recognized as an important indicator of cardiovascular risk. This study aimed to determine the effects of blood pressure and sex factor on the change of wave reflection using Gaussian fitting method. One hundred and ninety subjects were enrolled. They were classified into four blood pressure categories based on the systolic blood pressures . Each blood pressure category was also stratified for sex factor. Electrocardiogram (ECG) and radial artery pressure waveforms (RAPW) signals were recorded for each subject. Ten consecutive pulse episodes from the RAPW signal were extracted and normalized. Each normalized pulse episode was fitted by three Gaussian functions. Both the peak position and peak height of the first and second Gaussian functions, as well as the peak position interval and peak height ratio, were used as the evaluation indices of wave reflection. Two-way ANOVA results showed that with the increased blood pressure, the peak position of the second Gaussian significantly shorten ( The shapes of artery pressure waveform are determined by the cardiac ejection function and the mechanical and geometric properties of the systemic arteries. Changes of the artery pressure waveform features have been accepted as the risk indicators of cardiovascular diseases et al and Segers et al reported that wave reflection sites shift proximally toward the heart with the advancing age et al found that the wave reflection sites exhibit distal shifts with the advancing age due to the impedance fitting between the central aorta and proximal muscular arteries et al used a combination of artery pressure waveform analyses and 3D MRI to locate the reflection sites and suggested that the major reflection sites did not change with aging until 65 years of age but shifted distally thereafter O'ourke Recently, the model-based pulse decomposition methods have been used for the pulse forward and backward propagation analysis. In this case, the artery pressure waveform is often decomposed into several independent sub-waves using the different mathematic functions, such as the triangular The previous studies have showed that the wave reflection changed with the age and hypertension factors when using the traditional clinical indices, such as pulse wave velocity (PWV), augmentation index (AI), reflection index (RI) and stiffness index (SI) One hundred and ninety subjects  were enrolled at the Qilu Hospital of Shandong University. All subjects gave their written informed consents to participate in the study, and confirmed that they had not participated in any other ‘clinical trial’ within the previous three months. The study obtained a full approval from the Clinical Ethics Committee of the Qilu Hospitals of Shandong University and all clinical investigation was conducted according to the principles of expressed in the revised guidelines of Declaration of Helsinki – the fifth revision in the Edinburgh 2000 A comprehensive subject sample including the healthy volunteers (n = 57) and the cardiovascular disease subjects (n = 133) was included in this study. The cardiovascular disease subjects included: coronary heart disease (n = 53), congestive heart failure (n = 42) and dyslipidemia (n = 38). The coronary heart disease subjects should be consistent with one of the following symptoms: 1) The electrocardiogram (ECG) waves presented a typical myocardial infarction abnormality; or 2) A horizontal or oblique downward superior to 0.1 mV could be found on the ECG ST-segment. The congestive heart failure subjects should be consistent with one of the following symptoms: 1) Accord with the class II-III of the New York Heart Association (NYHA) Functional Classification; or 2) Left ventricular ejection fraction (LVEF) is lower than 50% with ultrasonic cardiogram (UCG) detection. The dyslipidemia subjects should have a higher low-density lipoprotein, total cholesterol or triglycerides. The healthy volunteers should have the normal performances in the UCG and ECG checks. Women who were pregnant or subjects with severe organ damage or psychiatric disorders had been excluded. No subjects had taken medications or smoked cigarettes before the test. All of the potential risks and procedures of the study were explained to the subjects, and they gave their written informed consent to participate in this study.The standard limb II-lead ECG and RAPW signals were synchronously recorded with a sampling rate of 1000 Hz for more than 1 min and were converted into digital signals using a 16-bit A/D data acquisition card . During the signal recording, the subjects were asked to keep the regular and gentle breathing. Auscultatory SBP and DBP were recorded manually at the beginning and end of the signal recording from the right brachia. The mean arterial pressure (MAP) and pulse pressure (PP) were calculated using the classic formula: MAP  =  DBP + (SBP−DBP)/3 and PP  =  SBP-DBP. For each subject, SBP, DBP, MAP and PP all used the mean value of the two measurements.Let f1(n), f2(n) and f3(n). Each Gaussian function kf(n)  had 1000 points  and was determined by three sub-wave parameters: the peak height kH, half-width kW and peak position kC. The Gaussian functions are defined as follows:n = 1, 2, …, 1000, k = 1, 2, 3, and kC satisfies the following condition: 1<C1<C2<C3<1000.Our previous study kH, kW and kC were determined, the superimposed curve f of the three Gaussian functions was regarded as the fitted curve for the normalized pulse episode S(n):x =   was the sub-wave parameter vector. The objective function for optimization can be defined as follows:After the nine parameters C1 and C2) and peak height (H1 and H2) indices from the first and second Gaussian functions, as well as two derived indices: the peak position interval between these two Gaussian functions defined as Cref-forw  =  C2–C1 and the peak height ratio between them defined as Href/forw  =  H2/H1. All six indices were calculated by averaging the results from the ten successive normalized pulse episodes.For Gaussian fitting method, the first Gaussian is usually regarded as the forward component and the second Gaussian is usually regarded as the main reflected component P<0.05. All statistical analysis was performed using the Statistical Package for Social Sciences .Two-way ANOVA was used to examine the effects of blood pressure and sex on the selected physiological variables and the evaluation indices. All of the data were reported as number (No.) or mean±standard deviation (SD). Statistical significance was set a priori at P<0.01) whereas they have no significant differences in the sex category . Age and LVET variables have no significant differences in either the sex or SBP category . The other four variables  have significant differences in the sex category  but only body mass and body mass index have significant differences in the SBP category (both P<0.05). In addition, all variables have no significant differences for the interaction between the sex and SBP categories .P>0.05). However, all six indices have significant differences  in the SBP category except for the peak position C1. In addition, all six indices have no significant differences for the interaction between the sex and SBP categories .C2 significantly shorten (P<0.01), the peak height H1 significantly decreased (P<0.01) and the peak height H2 significantly increased (P<0.01), inducing the significantly decrease of the peak position interval Cref-forw (P<0.01) and the significantly increase of the peak height ratio Href/forw (P<0.01).For both men and women subjects, with the increase of SBP, the peak position The previous studies have showed that the wave reflection changed with the age C2 became smaller with the increase of blood pressure, indicating that the main backward component of pulse occurs earlier. Meanwhile, with the increase of blood pressure, significantly lower of the peak height H1 and higher of the peak height H2 were found. The former shows the amplitude decline of the forward component, which can indicate the strength decline of the ejecting blood function of left ventricle. The latter shows that the amplitude increases of the backward component, which may be caused by the increase of artery stiffness. Similar results were also reported in C1 had no significant change with the increase of blood pressure, showing that the stable occurrence of the forward component of arterial pulse. In addition, all evaluation indices have no significant differences in the sex category , and also have no significant differences for the interaction between the sex and SBP categories , verifying that the sex factor does not take a part in the change of wave reflection in the peripheral artery.As traditionally accepted, the first Gaussian is more likely to be linked with the ejecting blood function of left ventricle and could be regarded as the forward component of arterial pulse There are also several widely used clinical indices  for the assessment of wave reflection in clinical practice One unique aspect of the current study is to use the TSPSO algorithm to achieve the accurate waveform fitting. We have reported that the TSPSO method could achieve a high fitting accuracy for the RAPW signal


Ultrafiltration (UF) of excess fluid activates numerous compensatory mechanisms during hemodialysis (HD). The increase of both total peripheral and splanchnic vascular resistance is considered essential in maintaining hemodynamic stability. The aim of this study was to evaluate the extent of UF-induced changes in hepato-splanchnic blood flow and resistance in a group of maintenance HD patients during regular dialysis.RI) and hepato-splanchnic perfusion index (QI) were measured in 12 chronic HD patients using a modified, non-invasive Indocyaningreen (ICG) dilution method. During a midweek dialysis session we determined RI, QI, ICG disappearance rate (kICG), plasma volume (Vp), hematocrit (Hct), mean arterial blood pressure (MAP) and heart rate (HR) at four times in hourly intervals (t1 to t4). Dialysis settings were standardized and all patient studies were done in duplicate.Hepato-splanchnic flow resistance index (Vp dropped from 3.65 ± 0.77L at 1t to 3.40 ± 0.78L at 4t, and all patients remained hemodynamically stable. In all patients RI significantly increased from 12.40 ± 4.21 mmHg∙s∙m2/mL at 1t to 14.94 ± 6.36 mmHg∙s∙m2/mL at 4t while QI significantly decreased from 0.61 ± 0.22 at 1t to 0.52 ± 0.20 L/min/m2 at 4t, indicating active vasoconstriction. In diabetic subjects, however, RI was significantly larger than in non-diabetics at all time points. QI was lower in diabetic subjects.In the whole study group mean UF volume was 1.86 ± 0.46 L, In chronic HD-patients hepato-splanchnic blood flow substantially decreases during moderate UF as a result of an active splanchnic vasoconstriction. Our data indicate that diabetic HD-patients are particularly prone to splanchnic ischemia and might therefore have an increased risk for bacterial translocation, endotoxemia and systemic inflammation. Ultrafiltration (UF) induced hypovolemia activates a variety of compensatory mechanisms to maintain hemodynamic stability during hemodialysis (HD). However, failure of the hemodynamic response to counterbalance central hypovolemia and inadequate plasma refilling may lead to intradialytic hypotension, an acute complication occurring in 15 to 30% of HD treatments . ResultsThe aim of our study therefore was to investigate the magnitude of ultrafiltration-induced changes in hepato-splanchnic resistance and perfusion in a group of stable end stage kidney disease (ESKD) patients during regular dialysis treatments.The study was done in accordance with the Declaration of Helsinki at the Clinical Division of Nephrology, Medical University of Graz, Austria. All patients gave their written informed consent prior to this study, which was approved by the Institutional Review Board of the Medical University of Graz (registration number 23–056 ex 10/11). Subjects with abnormal liver function tests or other hepatic disease were excluded. Patients were studied during their regular midweek treatment with either HD or online hemodiafiltration (HDF) delivered in post-dilution mode. Patients were studied in supine body position and were fasting prior to and during the study period to rule out hemodynamic perturbances of the splanchnic region caused by food intake . The ultQ) was measured using a modified indocyanine green (ICG) dilution method as described elsewhere . IC. ICQ) walsewhere . ICG is MAP) and heart rate (HR). Hepato-splanchnic resistance (R) was estimated from the ratio of mean arterial pressure to hepato-splanchnic blood flow (Q) assuming negligible hepatic venous pressure. For practical reasons resistance is given in non-SI peripheral resistance units .Hemodynamics were assessed by mean arterial pressure (A) to obtain hepato-splanchnic flow index  and hepato-splanchnic resistance index , respectively. Body surface (A) was calculated according to the Du Bois formula [To account for differences in body size, hepato-splanchnic blood flow and resistance were normalized for body surface area .Hemodynamic data obtained in subsequent treatments were averaged to account for repeated measurements in the same subject Results are presented as the mean value ± SD or the median and interquartile range. Normal distribution of the data was verified by the Kolmogorov-Smirnov test. Statistical methods used were two-sample 1t to 36.72 ± 2.01% at 4t (p = 0.003), paralleled by a decrease in plasma volume from 3.65 ± 0.77 to 3.40 ± 0.78 L (p = 0.008). Heart rate and mean arterial pressure did not change during the study period. All study subjects exhibited an ICG-PDR of larger than 10% ((Q) by ICG-Clearance [QI) dropped from 0.61 ± 0.22 at 1t to 0.52 ± 0.20 L/min/m2 at 4t . Hepato-splanchnic vascular resistance index (RI) increased from 12.40 ± 4.21 at 1t to 14.94 ± 6.36 PRU∙m² at 4t . The comparison of flow to resistance confirmed the expected hyperbolic relationship for constant mean arterial pressure with flow decreasing as resistance increased (RI) into conductance (1/RI) provided the expected linear relationship with flow increasing as conductance increased  chronic HD-patients in whom ESKD was due to diabetic nephropathy  (three), focal segmental glomerulosclerosis (one), bilateral nephrectomy due to urothelcarcinoma (one), gestosis (one), hemolytic-uremic syndrome (one), unknown (two), interstitial nephritis (one), hypertensive glomerulosclerosis (one), and amyloidosis secondary to Crohn´s Disesase with ankylosing spondylitis (one). As Crohn’s Disease may affect hepato-splanchnic blood flow depending on disease activity , 18, a cthan 10% , a prere2t and 3t, barely missing significance at 1t and 4t (RI) in this cohort  to maintain a constant ICG concentration (bc) in arterial or mixed venous blood is used to calculate clearance (K) as the ratio of infQ to bc (K = Qinf/cb). This, however, requires a constant plasma volume and a steady state distribution of red blood cells [k, in 1/min) is determined by the slope of this line. The rate constant quantifies the disappearance rate (in 1/min or %/min) and the half-life (in min), but it is insufficient to quantify hepatic clearance (K) and hepato-splanchnic blood flow (Q) as the measurement of clearance (K = k∙V) also requires quantitative information on the distribution volume (V). Non-invasive devices used for measurement of ICG disappearance rate only report the elimination rate constant, which provides useful information on hepatic function, but fail to measure hepatic clearance or hepato-splanchnic blood flow. This discrepancy is clearly seen in our data where elimination rate remained almost unchanged without differences between diabetics and non-diabetics  obtained in 12 subjects in two subsequent studies. Abbreviations: F: female; M: male; DM: diabetic; ND: non-diabetic; BMI: body mass index; BSA: body surface area; Vuf: ultrafiltration volume; MAP: mean arterial pressure; HR: heart rate: Hct: hematocrit: Vp: plasma volume: QI: hepato-splanchnic blood flow index: ICG-DR, Indocyanine green disappearance rate: RI, hepato-splanchnic vascular resistance index; numbers behind variables refer to measuring times t.Original data of individual measurements ((XLSX)Click here for additional data file.


This study investigated the chronic and acute influence of resistance exercise on blood pressure in women with metabolic syndrome before and after climacteric. Twenty sedentary women, nine non-menopausal (RNM) and 11 menopausal (RM), performed training for 12 weeks. Meanwhile, 23 controls, 11 not menopausal (CNM) and 12 menopausal (CM), remained sedentary. Blood pressure was measured before and after the training period in conditions of rest and after a session of exercise. Training promoted variations in blood pressure at rest from 116±13 to 118±10 mmHg (p=0.73) and from 128±12 mmHg to 120±11mmHg (p=0.12) in RNM and RM, respectively. CNM and CM varied from 115±11 to 116±12 mmHg (p=0.9) and from 115±14 mmHg to 116±13 mmHg (p=0.74). Blood pressure values in one acute session did not differ between groups (p>0.05). Resistance training did not improve blood pressure in women with metabolic syndrome, regardless of climacteric. Menopause is a phenomenon that is characterized by changes in lipid profile and weight gain . These fIt is generally known that physical exercise effectively reduces blood pressure . HoweverAcute and chronic blood pressure reductions have been demonstrated in postmenopausal women . HoweverThis study analyzed the influence of a resistance training protocol on resting blood pressure and blood pressure responses to a single session of exercise in non-menopausal and menopausal women with metabolic syndrome.Forty-three women with metabolic syndrome participated in the study. Twenty nonmenopausal and twenty-three menopausal women were classified in accordance with the The 43 volunteers were randomly divided into four groups: resistant exercises, not menopausal , resistant exercises, menopausal ; control, not menopausal ; and control, menopausal . The sample power was previously calculated based on the study of Earth et al. (2008), who found a reduction in systolic blood pressure from 125.2 ± 9.3 mmHg to 114.7 ± 9.2 mmHg in older women who performed resistance exercises for 12 weeks, which produced an effect size of 1.22. The adoption of an alpha error of 5% and statistical power of 0.90 produced a minimum n of 8 subjects in each group in this investigation. The Ethics Committee on Human Research of the Federal University of Ceará approved this study under the protocol number 42111/2011. Each subject was informed of the risks and benefits of the study and signed an informed consent form, according to the Resolution 196/96 of the National Health Council.RNM and RM groups performed a training protocol with resistance exercises that lasted 14 weeks. Blood pressure measurements were performed in exercise and control groups before and after training. Blood pressure measurements were taken in the first and last session before exercise and after a period of 60 minutes, which was determined as the recovery period after exercise for evaluation of acute blood pressure responses. Control groups participated in these two exercise sessions only.The subjects underwent two weeks of adaptation to the exercises that would compose the training series before the start of the study. There were two sessions each week, with a 48-hour break between sessions. The study participants performed a series of 15 repetitions for each exercise with a load that they considered easy ), as proposed by Twenty-four hours after the adaptation phase, a 10RM test was performed for each of the exercises in the training protocol. The test was performed based on the protocol proposed by the Training was conducted with exercises that worked all major muscle groups. Therefore, we adopted the following exercises: upper limbs: pulley, bench press, biceps curl and triceps French; and legs: leg extension, leg curl, squat, plantar flexion.th to 8th weeks, but the number of sets, repetitions, subjective perception of effort and rest periods between sets and exercises remained constant. The load progressed to 70 – 80% of 10RM from the 9th through the 12th weeks, the effort perception increased to 6–8 in the OMNI - RES scale, and the number of repetitions decreased to 10 to 12. The number of sets and rest periods remained constant.The training protocol was developed so that there was a progression of training loads throughout the 12 weeks. Therefore, drills were performed with one to three sets of 15 to 18 repetitions with a load of 50% of 10RM in the first four weeks so that the subjects covered 4 to 6 on the OMNI-RES scale; a 1.5 min rest period was allowed between sets and exercises. The load increased to 60% of 10RM from the 5Nutritional assessments were performed before the beginning, in the middle and at the end of the training period using a food frequency questionnaire, following the proposal of Resting pressure measurements were taken 24 hours before the beginning of the adaptation to the exercise phase and 48 hours after the last session of the training protocol to evaluate the influence of the training protocol on blood pressure.Pressure measures to a single session of exercise were performed on the first and the last session of the training protocol. Women were seated at rest for 10 minutes before exercise to take basal blood pressure. They performed the exercise session, and sat down immediately afterwards. New blood pressure measurements were taken immediately after exercise every 10 minutes during a recovery period of 60 minutes in which women remained seated.Blood pressure was measured by auscultation using a Missouri sphygmomanometer  purchased solely for the purposes of this research after going through a certification process for calibration. The proposal of the The normality and homogeneity of variance in the data were analyzed using the Shapiro- Wilks and Levene tests, respectively. A one-way ANOVA was used to compare the pre-intervention values between groups. A two-way ANOVA was used to analyze changes in cardiovascular variables with groups and time points (before and after intervention) as factors. For all analyses, p<0.05 was adopted as statistically significant, and post-hoc comparisons were performed using the Newman-Keuls test, when necessary. Data are presented as means ± standard deviation.All subjects had hypertension as a component of their metabolic syndromes. They were previous users of antihypertensive medications, such as angiotensin converting enzyme (IACE), beta-blockers and diuretics, and they remained on the same medications and dosages throughout the study. The women showed controlled blood pressure before starting the study despite being hypertensive. The menopausal women in the control and experimental groups showed levels of total lipoproteins and fasting glucose above the upper limit recommended by the CM, RNM and RM showed a slight post-exercise hypotension in DBP at the pre-training intervention  as shown in The results of this study indicate that a training program with resistance exercises does not reduce blood pressure significantly in women with metabolic syndrome regardless of menopause status. A single session of resistance exercise modestly promoted an acute reduction in blood pressure in these women, and the implementation of a training program did not affect this response.We did not find significant chronic alterations in blood pressure in response to the adopted training protocol, but we observed a blood pressure decrease from 7 mmHg to 9 mmHg and from 1 mmHg to 9 mmHg in systolic and diastolic blood pressure, respectively, in the group of menopausal women who participated in the physical training program. This reduction was not significant, but the average values were higher than the meta-analysis of Our sample was composed of subjects with hypertension, but the blood pressure values in the pre-intervention were close to normal values. The training protocol was updated to include a progression of charges in loads over the 12 weeks of training. The adoption of the effort subjective perception scale of OMNI-RES assured that the intensity was updated according to the strength gains obtained. Therefore, we believe that the absence of a significant reduction in resting blood pressure did not happen due to failures in the adequacy of the training load over 12 weeks.It is well-established that reductions in blood pressure occur during the first minutes after a single exercise session compared to basal levels . Two preThe single session performed after 12 weeks of training resulted in sub-acute pressure responses similar to the pre-training session, which indicates that the exercise program did not affect post-exercise hypotension. The inclusion of sub-acute blood pressure responses to an exercise session in this study was motivated by the fact that, although post-exercise hypotension is a well-established phenomenon, the effects of training on this response are not known. A reduction in blood pressure at rest is usually observed after a training protocol, but we expected that sub-acute blood pressure reduction levels were diminished due to the lower basal values of blood pressure. However, the absence of post-exercise hypotension prevented us from answering whether chronic blood pressure reductions in resting blood really minimized the magnitude of post-exercise hypotension.These considerations suggest that the initial level of blood pressure is a variable that should be taken into account in future studies of physical training. Therefore, we recommend that future studies assess the effectiveness of resistance exercise training by forming subgroups of hypertensive subjects who have initial blood pressure values above and below 140/90 mmHg, which are the borderline values for determining whether blood pressure is controlled.Previous studies verified chronic reductions in the blood pressure, but our study using resistance exercise training did not promote chronic reductions in blood pressure in women with metabolic syndrome. The condition of menopause was not an influential variable on blood pressure responses to exercise. Despite the absence of chronic blood pressure reductions, data from this study indicate a modest capacity of resistance exercise to promote acute reductions in blood pressure in women with metabolic syndrome.


Omega–3 fatty acids prevent cardiovascular disease (CVD) events in patients with myocardial infarction or heart failure. Benefits in patients without overt CVD have not been demonstrated, though most studies did not use treatment doses (3.36 g) of omega-3 fatty acids. Arterial stiffness measured by pulse wave velocity (PWV) predicts CVD events independent of standard risk factors. However, no therapy has been shown to reduce PWV in a blood pressure-independent manner. We assessed the effects of esterified omega–3 fatty acids on PWV and serum markers of inflammation among patients with hypertension.We performed a prospective, randomized; double-blinded pilot study of omega-3 fatty acids among 62 patients in an urban, safety net hospital. Patients received 3.36 g of omega–3 fatty acids vs. matched placebo daily for 3-months. The principal outcome measure was change in brachial-ankle PWV. Serum inflammatory markers associated with CVD risk were also assessed.p = 0.36 for difference, after multivariate adjustment for baseline age, systolic blood pressure, and serum adiponectin). Non-significant reductions in lipoprotein-associated phospholipase A2 (LpPLA2) mass and high sensitivity C-reactive protein (hsCRP) relative to placebo were also observed .The majority (71 %) were of Latino ethnicity. After 3-months, mean change in arterial PWV among omega-3 and placebo groups was −97 cm/s vs. −33 cm/s respectively (High-dose omega-3 fatty acids did not reduce arterial PWV or markers of inflammation among patients within a Latino-predominant population with hypertension.NCT00935766, registered July 8 2009. The effects of omega-3 fatty acids on cardiovascular disease (CVD) outcomes have been mixed. Prospective randomized trials have previously demonstrated reductions in CVD events among patients with myocardial infarction  and hearPending results of CVD outcome trials, an assessment of the effects of omega-3 fatty acids on preclinical predictors of CVD events may be informative. Omega-3 fatty acids reduce inflamation , but impArterial PWV is an independent predictor of CVD events among patients with hypertension  and is tWe conducted a prospective, randomized placebo-controlled, double-blind pilot study. Patients received either 4 omega-3 fatty acids  capsules or identically matched corn-oil placebo. Each Lovaza capsule includes 465 mg of EPA and 375 mg of docosahexaenoic acid (DHA) for a total daily dose of 3.36 g. The treatment period was 3-months with baseline and follow-up measurements performed in the morning in a fasted state. The Colorado Multiple Institutional Review Board approved the study and it was registered with clinicaltrials.gov. All study participants signed written informed consent.Subjects were recruited from outpatient primary care clinics or a preexisting registry of hypertension patients. This cohort consisted of 177 individuals; the inclusion and exclusion criteria for this registry have been previously reported . EligiblArterial PWV measurements were performed in the recumbent position. Supine blood pressure was measured in duplicate in the non-dominant arm. Bilateral brachial-ankle PWV was derived from the pulse transit time between and the estimated path length between proximal and distal arterial sites expressed as cm/s. Inflammatory markers and adiponectin were also assessed while fasting. We chose hsCRP because it has incremental CVD risk discrimination beyond standard Framingham risk factors  and Lp-PP-values <0.05 were considered statistically significant. SAS Version 9.4  was used for all statistical analyses.Means, standard deviations, and medians were calculated for all continuous variables. For univariate analyses, comparisons were made using analysis of variance, chi-squared or Wilcoxon rank sum tests. For change over time analyses, mixed-effects models were used to account for repeated measures within participants. Univariate associations between baseline risk markers and change in PWV were assessed, and multivariate models were fitted to assess for predictors of change. Sensitivity analyses were performed to assess changes in outcomes among the following subgroups: patients naïve to statin therapy, those with baseline systolic blood pressure ≥ 140 mm Hg, and diabetic patients, p < .0001), 7.3 cm/s increase in mean PWV per each mm Hg of higher systolic blood pressure (p = 0.005), and 14 cm/s per unit of adiponectin (p = 0.008).Baseline characteristics of the 62 participants are shown in Table p = 0.36). Reductions were also seen in mean hsCRP (−0.9 mg/L vs. 0.9 mg/L in placebo group) and Lp-PLA2 mass (−18.1 ng/mL vs. −6.1 ng/mL). Numeric mean reductions in risk markers were relatively larger within subgroups: Among 34 statin-naïve subjects, the difference in arterial PWV was larger (−82 vs. +50 cm/s), but remained non-significant (p = 0.20), though the reduction in mean hsCRP (− 0.8 vs. +1.6 mg/dl) achieved significance (p = 0.03). Among 31 diabetic subjects, PWV (−100 vs. −18 cm/s), hsCRP (−0.8 vs. +1.7 mg/L), and LpPLA-2 mass (−11.1 vs. −4.1 ng/ml) were non-significantly lower with active treatment . Among 24 subjects with baseline systolic blood pressure ≥ 140 mm Hg PWV (−98 vs. −65 cm/s), hsCRP (−1.0 vs. +0.8 mg/L), and LpPLA-2 mass (−32.7 vs. −3.2 ng/ml) were non-significantly lower with active treatment .Changes in risk factors, inflammatory markers, and PWV are shown in Table p = 0.36] was observed. In analysis including only time and treatment group, the reductions in hsCRP and Lp-PLA2 mass were numerically greater with omega-3 therapy, but were not statistically significant .In multivariate analysis accounting for baseline age, systolic blood pressure and adiponectin, no significant change in mean PWV [parameter estimate (standard error) = -22 (24), To our knowledge, this is the first prospective randomized trial evaluating the effects of prescription doses of omega-3 fatty acids on arterial stiffness in a Latino-predominant population. Short-term treatment with omega-3 fatty acids was not associated with a significant reduction in arterial PWV. Moreover, with the exception of a reduction in serum hsCRP among statin-naïve subjects, no significant improvements in markers of vascular inflammation were observed despite a high prevalence of obesity and diabetes. Given an association between the metabolic syndrome and increased arterial stiffness , a positA number of possible explanations for our findings merit consideration. One potentially important factor is the dose of omega-3 utilized. In one study, PWV was assessed among overweight patients receiving 2, 4, and 6-g of omega-3 fatty acids daily . ReductiAnother potential explanation for the findings in the current study is the relatively small sample size. Root and colleagues also found no reduction in PWV with omega-3 therapy in a short-term study of 57 patients . In asseIn addition, the relatively short duration of therapeutic exposure, may have limited our ability to detect alterations in vascular stiffness. There was also a numeric imbalance of subjects between arms, which likely reflects a chance finding in the randomization sequence given the small sample size. This theoretically may have made a Type II error more likely. Most importantly, however, no pharmacologic therapy to date has been shown to reduce PWV independent of blood pressure reductions, suggesting the possibility that any salutatory effects of omega-3 treatment on inflammation and plaque may be inadequate to alter vessel wall physiology.In conclusion, high-dose purified omega-3 fatty acids did not significantly improve arterial stiffness among hypertensive patients extending the negative results of previous studies. Given the absence of benefits of omega-3 fatty acids on CVD events in large randomized controlled clinical trials, this therapy cannot be uniformly recommended in primary prevention patients despite widespread use.


Hypertension is one of the most common causes of death across the globe. Many trials and drugs have been used for controlling the debilitating effects of hypertension. One such new class of drug is direct renin inhibitors (DRI), e.g., aliskiren, which block the renin-angiotensin system (RAS). It blocks the very first step in the RAS system. Multiple trials have been carried out debating the outcome of monotherapy and combination therapy with other classes of hypertensive drugs. Focus on compliance, adverse effects, and the cost have also been in the news. Extensive studies are still needed to justify the clinical use of a DRI in the effective treatment of hypertension. Hypertension is one among the leading factors that contribute towards the cardiovascular disease reported worldwide. It is defined as a condition in which the mean systolic blood pressure (SBP) is ≥ 140 mm of Hg and a mean diastolic blood pressure is ≥ 90 mm of Hg. According to the World Health Organisation (WHO), the overall prevalence of raised blood pressure in adults over 18 years of age was approximately 22% in 2014. The incidence of raised blood pressure is highest in Africa, where it is about 30% for both sexes. The lowest prevalence of hypertension is in America, where it is reported in about 18% of both sexes. Men (21%) in this region have a higher incidence than women do (16%). Men have a slightly higher prevalence of hypertension globally. The global prevalence and age distribution of hypertension is as represented in Figure The following data, compiled from the fact sheet published by the World Hypertension League and the International Society of Hypertension, sheds light on the current global status of hypertension. High blood pressure is responsible for about 9.4 million deaths and an estimate of 162 million years of life were lost in 2010 itself . It is aOver the years, many strategies and drug approaches have been used to reduce the hazardous effects of hypertension. The drug, aliskerin, is a comparatively new drug available for the treatment of hypertension. This paper shall thus review the safety, efficacy, and its use alone or in combination with other hypertensive drugs .Aliskiren -N-(2-carbamoyl-2-methylpropyl)-5-amino-4-hydroxy- 2,7-diisopropyl-8-[4-methoxy-3-(3-methoxypropoxy-)phenyl)-octanamide was approved for the first time as a drug for hypertension by the US food and Drug Administration in March 2007. The structure of the compound is as given below  has been the leading cause of end-stage renal disease . Drugs sOn administration of aliskiren, a reduction in levels of proteinuria and hypertension have been noted. The use of aliskiren has been shown to decrease tubulointerstitial fibrosis, oxidative markers, glomerular pressure, and podocytopathy -35.In a randomized, double-blinded, placebo-controlled, multinational study, the use of aliskiren for 24 weeks showed a 20% reduction in albuminuria with small differences in blood pressures. Five hundred and ninety-nine hypertensive patients with Type 2 diabetes and nephropathy on treatment with losartan (100 mg per day) were randomly selected for aliskiren treatment or placebo. The study concluded that aliskiren does have an additional renoprotective effect with mild lowering of blood pressure properties when used in combination to ARBs .Another similar study conducted to learn about the effectiveness of dual therapy over monotherapy in the management of the cardiovascular and renal system was stopped due to adverse effects, including hypotension, hyperkalemia, and acute renal injury, with the use of ACEI and ARB . This stThe Aliskiren Trial on Acute Heart Failure Outcomes (ASTRONAUT) was conducted to study the effects of DRI with ACEI/ARB vs placebo with ACEI/ARB in hypertension. The result indicates that there is no significant difference in cardiovascular parameters under DRI treatment . The sumA recent study published in the European Heart Journal carried out by Tea, et al. focuses on the use of aliskiren as monotherapy or in combination with other hypertensive drugs. The study was a randomised placebo-controlled clinical trial, including aliskiren (300 mg) and hydrochlorothiazide (HCTZ) (25 mg) or amlodipine (5 mg). The group that had received aliskiren treatment showed a significant improvement with 35% of them reporting an average SBP of < 130 mm Hg and 11% of them with < 120 mm Hg as compared to 22.8% and 6.8% in the placebo groups .Similarly, in another study named the ONTARGET , the patients who were treated with DRI and ramipril/telmisartan as combination therapy led to a reduction of 2-3 mm of Hg in SBP when compared to that of those who received monotherapy. However, no benefit was observed in cases of stroke, myocardial infarction, or hospital stay for heart failure -41. As per the research conducted by Oparil and co-workers, aliskiren and valsartan were found to be better when given in combination as the dual blockage of RAAS reduces the blood pressure more effectively .The ACCELERATE  trial was a single-blinded placebo run with three consecutive phases of double-blind active treatment. Out of 315 patients enrolled in the study; 50% of the patients were treated with DRI (150 mg) while the other 50% were treated with amlodipine (5 mg) monotherapy during Phase I up to 16 weeks. Phase II was from 16 to 24 weeks where the patients received a combination of the drugs; in Phase III, a few patients received hydrochlorothiazide or placebo depending upon their BP. The SBP and DBP were measured at 8, 16, and 24 weeks, which showed a decrease of 6.5 mm of Hg in monotherapy and 1.4 mm of Hg in combination. The results were promising with DRI until Phase II; it was highly recommended to use a combination of both the drugs to reduce the BP rather than as a monotherapy .Another study called The HOPE  trial concluded that ramipril can significantly reduce the cardiovascular morbidity and mortality in people suffering from heart diseases . Anderse2) who were suffering from hypertension and left ventricular hypertrophy (LVH) to undergo treatment with DRI or ARB or both. The DRI in consideration was aliskiren and ARB was losartan. The trial showed that DRI can effectively reduce the LVH, which is an important sign of end organ damage and, hence, is a safe drug. Controversies following the ATTITUDE trial crept in, questioning the safety of the drug, but this trial proved that there was no difference in adverse effects in both the groups [The (Aliskiren in Left Ventricular Hypertrophy) ALLAY trial, registered obese patients (body mass index > 25 kg/me groups .The ALOFT (Aliskiren Observation of Heart Failure Treatment) trial shed light on the potential benefit of using DRI in patients with heart failure. The study was a randomised controlled trial considering beta blockers, ACEI, and DRI. The result revealed that there was a significant reduction in brain natriuretic peptide (BNP) concentration in groups receiving DRI . The addThe ATMOSPHERE trial is being conducted to determine the safety and efficacy of aliskiren and enalapril combination on morbi-mortality in patients with congestive heart failure. The APOLLO  trial aims to determine the action of aliskiren alone and in combination with HCTZ or amlodipine in patients above 65 years. The AQUARIUS (Safety and Efficacy of Aliskiren on the Progression of Atherosclerosis in Coronary Artery Disease Patients) intends to study the change in coronary atherosclerotic disease through aliskiren treatment .Aliskiren is capable of conferring increased insulin sensitivity, both in humans and animals, after a high fructose diet. Aliskiren achieved this via effectively decreasing the angiotensin II formation. Male Sprague-Dawley rats demonstrating hypertension, hyperinsulinaemia, insulin resistance, hyperglycemia, hypercholesterolemia, and hypertriglyceridaemia after a high-fructose diet were shown to resume normalcy by the administration of subcutaneous aliskiren (100 mg/kg/daily). Obese mice that were supplemented with a fat-rich diet showed a reduction in plasma leptin levels and insulin resistance post-administration of aliskiren -52.A recently published work by a group of researchers has proved to be an eye-opener for diabetic patients suffering from hypertension. The study revolved around the efficacy and safety of DRI against CCB/ARB in hypertensive patients with Type 2 diabetes mellitus. It was comprised of 126 patients who were treated for 24 weeks with aliskiren and CCB/ARB. The results revealed a significant reduction in SBP and DBP with DRI, i.e, 11.37% and 10.67%, respectively, while patients with CCB/ARB showed a reduction of 8.47% and 9.28%, respectively. DRI also showed a significant reduction in microalbuminuria as compared to CCB/ARB after a period of six months. Hence, the addition of aliskiren to regular hypertensive drugs can be highly effective in reducing the blood pressure and urinary albumin excretion -57.An original cohort study discussing the drug costs and compliance of DRI with ACEI and ARB have been published recently. The study had included 17,902 patients out of which 1,395 patients were on aliskiren. Aliskiren was used in conjunction with valsartan  in one cohort, and in the other, valsartan was used with lisinopril . The mean age in the aliskiren group was 66.4 and that of the ACEI with ARB group was 64.5 years. About 42.7% were males and 51.6% were women. Patients on DRI with ARB demonstrated less discontinuation rate, better compliance, and less hospitalisation when compared to that of ACEI and ARB . In an oA study focused on determining the overall medical services cost per patient with hypertension found out that DRI, plus ARB treatment, requires $1,584 and ACEI and ARB requires only $734. The cost difference was $850. The exclusive hypertension-related medical services cost averages around $1,292 per patient for DRI and ARB, in contrast to $656 with ACEI and ARB . The stuIt can thus be concluded the prospective of using aliskiren as a combination therapy along with a conventional hypertensive drug is highly promising. However more research and clinical trials are required to carefully devise a safe and effective treatment course. Furthermore, owing to the relative higher cost to DRI drugs when compared to other conventional drugs, research is also warranted in a direction to reduce the cost of DRI drugs under study so that patients can benefit from the advantages of using them without a significant economic burden.


Objective. Methotrexate (MTX), the most used drug in rheumatoid arthritis (RA) treatment, showing variability in clinical response, is often associated with genetic polymorphisms. This study aimed to elucidate the role of methylenetetrahydrofolate reductase (MTHFR) C677T and aminoimidazole carboxamide adenosine ribonucleotide transformylase (ATIC) T675C polymorphisms and clinicopathological variables in clinical response to MTX in Portuguese RA patients. Methods. Study included 233 RA patients treated with MTX for at least six months. MTHFR C677T and ATIC T675C polymorphisms were genotyped and clinicopathological variables were collected. Statistical analyses were performed and binary logistic regression method adjusted to possible confounding variables. Results. Multivariate analyses demonstrated that MTHFR 677TT  and ATIC 675T carriers  were associated with over 4-fold increased risk for nonresponse. For clinicopathological variables, noncurrent smokers , patients positive to anti-cyclic citrullinated peptide  and antinuclear antibodies , with higher health assessment questionnaire score , and nonsteroidal anti-inflammatory drug users  were also associated with nonresponse. Contrarily, subcutaneous administration route  was associated with response. Conclusion. Our study suggests that MTHFR C677T and ATIC T675C genotyping combined with clinicopathological data may help to identify patients whom will not benefit from MTX treatment and, therefore, assist clinicians in personalizing RA treatment. Rheumatoid arthritis (RA) is a chronic disease characterized by an inflammation of the joints with an autoimmune profile and the most widely used disease modifying antirheumatic drug (DMARD) for RA treatment is methotrexate (MTX) . Despite status [ de novo purine synthesis pathway responsible for the conversion of AICAR into formyl-AICAR (FAICAR), is directly inhibited by MTXPG, causing intracellular accumulation of AICAR [MTX is an antifolate drug, with antiproliferative and anti-inflammatory effects, by inhibition of folate and adenosine pathways and also inhibition of purines and pyrimidines synthesis  16, 20,,20, 21.  MTHFR and ATIC genes [ MTHFR is C677T (rs1801133), which is responsible for a substitution of an alanine to a valine, leading to a thermolabile form of MTHFR with reduced activity [ MTHFR 677T allele is related to MTX nonresponse in RA [ ATIC, of which the ATIC 675C allele has been associated with improved clinical status and, consequently, with clinical response to MTX [Several studies have demonstrated that the occurrence of variations on clinical response to MTX could be explained by genetic polymorphisms inIC genes , 24–28. activity . In fact7T rs18013, which e to MTX , 26. MTHFR C677T and ATIC T675C polymorphisms, in Portuguese RA patients.The pattern of MTX therapeutic outcome is considered to be a major factor for the motivation of researchers and clinicians to enroll patients in pharmacogenetic studies, mainly by comparative studies within different populations. Therefore, the aim of this study was to elucidate the association of clinical response to MTX with per os (PO)/week of MTX in monotherapy. This dose was increased 5 mg at each three weeks if patients did not meet EULAR criteria for response, that is, if presenting a disease activity score in 28 joints (DAS28) > 3.2. At three months, if patients were still without response, the administration route was changed from PO to subcutaneous (SC) maintaining the MTX dose. If within three months, using SC at the maximum tolerable doses, patients did not meet the response criteria, MTX therapy was associated with other synthetic DMARDs. After three more months, if patients continued without response in two successive evaluations and did not present any contraindication, MTX therapy was discontinued or associated with biological DMARDs. The adjustment of MTX therapy also occurred when patients developed MTX-related toxicity. Due to the well-known protective effect of folic acid supplementation for the prevention of toxicity occurrence, in particular for gastrointestinal disorders [This study was developed as a retrospective study in a cohort of consecutive Caucasian patients (≥18 years) with RA treated with MTX for at least six months and was conducted between January 2009 and December 2012 at São João Hospital Center . After diagnosis, patients were classified according to the 1987 criteria of the American College of Rheumatology (ACR) and reclassified according to the 2010 criteria of ACR and the European League Against Rheumatism (EULAR) . All patisorders –33, thisPatients were excluded from the study if not treated with MTX for at least six months and if there was history of drug abuse, recent pregnancy, or desire to become pregnant. The study procedures were considered according to the ethical standards of the Helsinki Declaration by the local Ethical Committee (reference 33/2009) and all patients provided a signed informed written consent.Clinicopathological data were collected from individual clinical records by clinicians during patients' regular hospital visits and include variables possibly influencing disease state and clinical response to MTX, which were selected based on either the literature review and/or the clinical significance , 17, 33.NPY was calculated by the formula: (number of cigarettes smoked per day × number of years smoking)/20. Comorbidity was defined as the presence of diabetes mellitus, hypertension, dyslipidemia, and/or cardiac disorders beyond RA. DAS28 was calculated as described by Prevoo et al. . Daily cMTX clinical response was recorded at the time of each visit. Nonresponse was defined if patients presented a DAS28 > 3.2 in two consecutive evaluations despite the use of MTX either in monotherapy or combined with other DMARDs. Therefore, at least six months of MTX therapy was required to define which patients had nonresponse to MTX. Response to MTX was defined when patients presented a DAS28 ≤ 3.2.Whole blood samples were obtained with standard venipuncture technique using ethylenediaminetetraacetic acid (EDTA) containing tubes and genomic deoxyribonucleic acid (DNA) extracted with QIAamp DNA Blood Mini Kit according to the manufacturer instructions . Total genomic DNA was quantified and its purity and integrity were analyzed using the NanoDrop 1000 Spectrophotometer v3.7 .MTHFR C677T and ATIC T675C polymorphisms were selected based on the role of MTHFR and ATIC in MTX action pathway, upon the putative alteration of these proteins levels and the consequent implication in MTX clinical response [response , 26, 29. MTHFR C677T and Hinks et al. [ ATIC T675C.Genotyping protocols were adjusted from those proposed by Sadananda Adiga et al.  for MTHFs et al.  for ATICMTHFR C677T polymorphism was genotyped by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) techniques. PCR amplification was performed for a final volume of 50 μL containing 0.3 μM of each primer , 1x DreamTaq Green master mix , and 50–100 ng of genomic DNA. The PCR conditions consisted of initial denaturation at 94°C during 5 minutes followed by 30 cycles with denaturation for 1 minute at 94°C, annealing for 1 minute at 57°C, extension for 15 seconds at 72°C, and a final extension at 72°C during 10 minutes. RFLP was performed at 37°C, overnight, using HinfI . Individuals with the CC genotype presented 1 fragment with 198 base pairs (bp), whereas individuals with the TT genotype presented 1 fragment with 175 bp.ATIC T675C polymorphism was genotyped using TaqMan SNP Genotyping Assay (C_362264_10) from Applied Biosystems  with fluorogenic binding probes. Reactions were performed on an Applied Biosystems 7300 Real Time PCR System  with a 5 μL final volume mixture containing 1x TaqMan Genotyping Master Mix , 900 nM of each primer, 200 nM of probes labeled with either FAM or VIC, and 10 ng of extracted DNA. Thermal cycling conditions were 10 minutes at 95°C followed by 40 cycles of 15 seconds at 95°C and 1 minute at 60°C. Allelic discrimination was performed by measuring endpoint fluorescence using ABI PRISM Sequence Detection System .For quality control, 10% of the samples were randomly selected for a second analysis and 10% percent of cases were confirmed by automated sequencing in a 3130xl Genetic Analyzer using the Kit BigDye Terminator v3.1 . Results were 100% concordant.P) value of 5% or less. The chi-square test was used to assess the association between the groups (response versus nonresponse) and the different categorical variables. Odds ratio (OR) and the correspondent 95% confidence intervals (CI) were calculated as a measure of the association between the categorical variables. For the comparison of quantitative variables two sample t-tests and nonparametric Mann-Whitney U tests were applied.Statistical analyses were performed using the IBM SPSS Statistics for Windows, Version 20.0 , considering a statistically significant probability (MTHFR C677T and ATIC T675C genotypes) and clinicopathological variables could predict risk for occurrence of nonresponse to MTX. This analysis was performed adjusting to potential confounding variables in three steps: (1) patient-related variables; (2) patient- and disease-related variables; and (3) patient-, disease-, and treatment-related variables.Multivariate analysis with binary logistic regression was used to identify which genetic variables (P < 0.001) and noncurrent smokers  were statistically significant associated with nonresponse to MTX. Concerning disease-related variables, our results demonstrated that positivity to anti-CCP  and ANAs  was statistically significant associated with nonresponse to MTX. Additionally, higher number of tender joints count (TJC) (P = 0.007) and swollen joints count (SJC) (P = 0.008) and higher health assessment questionnaire (HAQ) score (P = 0.006) were statistically significant associated with nonresponse to MTX. Considering the treatment-related variables, our results revealed that NSAIDs users  were associated with nonresponse to MTX. In addition, attending to MTX administration characteristics, higher MTX doses (P < 0.001) were associated with nonresponse to MTX, while SC administration route  was statistically significant associated with response to MTX. MTHFR C677T (rs1801133) genotypes were 105 CC (45.1%), 99 CT (42.5%), and 29 TT (12.4%), while for ATIC T675C (rs4673993) they were 110 TT (47.2%), 99 TC (42.5%), and 24 CC (10.3%). In our population, the minor allele for MTHFR C677T was T and for ATIC T675C was C . Considering distribution between responders and nonresponders, results showed significant differences for MTHFR C667T (P = 0.049) and ATIC T675C (P = 0.025) genotypes.The frequencies of MTHFR C677T polymorphism, our results showed that MTHFR 677TT was statistically significant associated with about 3-fold increased risk for nonresponse to MTX when compared to MTHFR 677CC  and MTHFR 677C carriers . Regarding ATIC T675C polymorphism, we observed that ATIC 675CC was associated with response to MTX when compared to ATIC 675TT  and ATIC 675T carriers .MTHFR C677T and ATIC T675C genotypes) could predict risk for the occurrence of nonresponse to MTX  and ATIC 675T carriers  were associated with about 3-fold increased risk for nonresponse to MTX. In a second step, beyond patient-related variables, disease-related variables were added and results confirmed that MTHFR 677TT  and ATIC 675T carriers  were associated with nonresponse to MTX. In a third step, beyond patient- and disease-related variables, treatment-related variables were added and the obtained results showed that MTHFR 677TT carriers  were statistically significant associated with more than 4-fold increased risk for nonresponse to MTX when compared to MTHFR 677C carriers. Additionally, ATIC 675T carriers  were statistically significant associated with more than 5-fold increased risk for nonresponse to MTX when compared to ATIC 675CC.Multivariate analysis with binary logistic regression was used to identify which clinicopathological and genetic variables (e to MTX . This anP = 0.001), positivity to anti-CCP  and ANAs , higher HAQ , and NSAIDs users  were statistically significant associated with nonresponse to MTX. Moreover, SC administration route  was statistically significant associated with response to MTX.Furthermore, considering clinicopathological variables, we observed that noncurrent smokers , changes in folate status, influence of less common single nucleotide polymorphisms (SNPs) in MTHFR and ATIC, polymorphisms in genes encoding to other intervenient proteins in folate, purine, pyrimidine, adenosine, and methionine pathways, and also differences in the definition of MTX clinical response [Previous studies revealed controversial results when clinicopathological variables were associated withresponse . MTHFR C677T and ATIC T675C polymorphisms is in accordance with the published literature for other Caucasian population [Besides the potential importance of our results, we are aware of possible limitations, especially the sample size. Despite this, patient characteristics are similar to those reported in the literature , 37. Ourpulation –26, 39. MTHFR C677T polymorphism, our results demonstrated a statistically significant association between MTHFR 677TT and nonresponse to MTX, which is in accordance with previously reported studies [ status of the cell [ MTHFR 677TT as responsible for a reduction of MTHFR activity [Regarding studies , 24. Altthe cell . Literatactivity , leadingactivity , 23, 40, ATIC T675C polymorphism, our results indicate that ATIC 675T carriers presented an increased risk for nonresponse to MTX, as previously reported [ ATIC 675T allele will lead to MTX nonresponse due to the increased conversion of AICAR to FAICAR , of which ATIC 347G carriers  have been reported as related to better response [ ATIC 675CC  and clinical response to MTX.Regardingreported , 26. To o FAICAR , causinge effect . Moreoveresponse , 43. Hen status, and higher disease activity [According to patient-related variables, multivariate analysis results demonstrated that noncurrent smokers were associated with nonresponse to MTX. Literature describes the association between smoking and decreased folate levels which, in fact, enhance the antifolate effect of MTX and, therefore, improve clinical response to MTX –46. Furtactivity , 52–55 aactivity , 57; nevactivity , 58. In activity . This tractivity , 59. In activity . Consequ MTHFR C677T, and T allele carrying for ATIC T675C can be possible predictive factors of nonresponse to MTX. Thus, the inclusion of these polymorphisms in combination with clinicopathological variables may add valuable information that may help to identify patients who will benefit from MTX treatment and assist clinicians to make better treatment decisions. Despite the potential of these findings, translation into clinical practice requires larger and multicentric studies in order to clearly endorse the importance of these polymorphisms.Our results suggested that noncurrent smoking, anti-CCP and ANAs positivity, higher HAQ, NSAIDs utilization, PO administration route, T homozygosity forMTHFR C677T and ATIC T675C polymorphisms of population enrolled in the study.Figure S1. Genotype distribution for ATIC: 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase; C: cytosine; MTHFR: methylenetetrahydrofolate reductase; T: thymine.MTHFR C677T genotypes and clinical response to methotrexate.Figure S2. Relation between P value <0.05 is considered to be of statistical significance (highlighted in bold) when compared to reference genotype(s). C: cytosine; MTHFR: methylenetetrahydrofolate reductase; T: thymine.MTHFR T675C genotypes and clinical response to methotrexate.Figure S3. Relation between P value <0.05 is considered to be of statistical significance (highlighted in bold) when compared to reference genotype(s). ATIC: 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase; C: cytosine; T: thymine.