We aimed to assess the differences in the gut microbiome among participants with different uric acid levels  and to develop a model to predict HUA based on microbial biomarkers.We sequenced the V3-V4 variable region of the 16S rDNA gene in 168 fecal samples from HUA patients (n=50), LSU patients (n=61), and controls (n=57). We then analyzed the differences in the gut microbiome between these groups. To identify gut microbial biomarkers, the 107 HUA patients and controls were randomly divided (2:1) into development and validation groups and 10-fold cross-validation of a random forest model was performed. We then established three diagnostic models: a clinical model, microbial biomarker model, and combined model.Proteobacteria (P<0.001) and genus Bacteroides (P=0.02) were significantly increased in HUA patients compared to controls, while the genus Ruminococcaceae_Ruminococcus was decreased (P=0.02). Twelve microbial biomarkers were identified. The area under the curve (AUC) for these biomarkers in the development group was 84.9% (P<0.001). Notably, an AUC of 89.1% (P<0.001) was achieved by combining the microbial biomarkers and clinical factors.The gut microbial α diversity, in terms of the Shannon and Simpson indices, was decreased in LSU and HUA patients compared to controls, but only the decreases in the HUA group were significant . The phylum The combined model is a reliable tool for predicting HUA and could be used to assist in the clinical evaluation of patients and prevention of HUA. ResearcFurthermore, low serum uric acid (LSU) is often overlooked. Some studies have shown that LSU  is associated with all-cause mortality and gender-specific cardiovascular mortality , but theBacteroides spp., Porphyromonadaceae, Rhodococcus, Erysipelatoclostridium spp., and Anaerolineaceae and decreases in Lachnospiraceae and Ruminococcaceae. In contrast, other gut microbes are capable of reducing intestinal uric acid production and/or increasing uric acid excretion. For example, Lactobacillus gasseri PA3 reduces exogenous purine absorption, including inosine 5-phosphate (IMP), inosine, hypoxanthine, guanosine 5-phosphate (GMP), and guanine nucleoside , reduce the production of uric acid precursors, and effectively reduce serum uric acid levels  to assess its clinical value.The study participants were aged 20–60 years old and were recruited from Balikun County Hospital, Xinjiang Province of China, from October 2019 to August 2021. All participants underwent physical examination in Balikun County Hospital. Height, weight, body mass index (BMI), blood pressure (BP), genetic and disease history, and drug use history were recorded.The study cohort was divided into the following three groups according to mean serum uric acid levels (measured on 2 days): LSU group  , controlThe study was approved by the Ethics Committee of the First Affiliated Hospital of Xinjiang Medical University . The sampling and other methods were carried out according to the approved guidelines. Each participant was informed about the study before study commencement, and they signed an informed consent form.http://www.personalbio.cn).We provided each participant with a sterile container for stool sample collection and training on sample collection. After stool sample collection, 0.2 g fresh fecal sample from each participant was quickly placed into five sterile centrifuge tubes and rapidly transported to the laboratory for freezing at -80°C. The bacterial DNA was extracted from the samples using the bead-beating method. The quality of DNA was assessed using 0.8% agarose gel electrophoresis . The DNAOperational taxonomic unit (OTU) clustering analysis was performed on all sequences. The Ribosomal Database Project (RDP) Bayesian classifier was used to classify the representative OTU sequences at the 97% similarity level. The community composition of each sample was assessed according to various classification levels , and the community composition was statistically compared between groups at each classification level. We used the heatmap R package to present clustering results at phylum and genus levels in heatmaps.α diversity analyses were used to assess the abundance and diversity (Shannon and Simpson indices) of microbial communities in the three uric acid-related groups. Using principal coordinates analysis (PCoA) of UniFrac distances and nonparametric analysis of similarities (ANOSIM), we assessed the similarity between the three uric acid-related groups. Additionally, we used linear discriminant analysis (LDA) effect size (LEfSe) to determine the specific gut microbes related to HUA.Peripheral venous blood samples of all participants were obtained after 12 h of fasting. Laboratory data, including serum biochemical indexes, liver function indexes, renal function indexes, and lipid results, were examined in the Balikun County Hospital as described previously.We established three diagnostic models: a clinical model, microbial biomarker model, and combined model. To establish the clinical model, we used univariate logistic regression analyses to identify significant clinical factors for predicting HUA followed by a receiver operating characteristic (ROC) curve analysis of each factor to select the most valuable factors for predicting HUA, based on the area under the ROC curve (AUC) values. Next, using the significant variables with AUC value >0.5, we used least absolute shrinkage and selection operator (LASSO) regression to determine the independent risk factors for HUA. The available clinical factors included blood pressure, blood urea nitrogen (BUN), creatinine, blood glucose, alanine aminotransferase, aspartate aminotransferase, triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C).votes/ntrees).To establish the microbial biomarker model, we used 10-fold cross-validation of a random forest model to ensure the reliability of the gut biomarkers. We randomly divided (2:1 ratio) the 107 volunteers in the HUA and control groups into the development and validation groups, and the former was used to construct the microbial biomarker model, while the latter was used to assess model reliability. The probability of disease (POD) index in the HUA and control samples in the development and validation groups was used to determine the diagnostic value of the gut microbial biomarkers. It was defined as the ratio between the number of decision trees that predicted “HUA” and the total number of sampling trees  and R software . The normally and non-normally distributed continuous variables are expressed as mean ± standard deviation (mean ± SD) and median, respectively. The categorical variables are presented as percentages. Regarding normally distributed continuous variables, the three uric acid-related groups were compared using a one-way analysis of variance (ANOVA). Differences between the HUA and control groups were determined using The study cohort comprised 168 Chinese adults, and it was divided into the LSU, control, and HUA groups Figure 1The Simpson and Shannon indices  were significantly lower in the LSU and HUA groups than in the control group, but only the decreases in the HUA group were significant  of UniFrac distances, there were significant separations between the HUA group and the other two groups Table S1Firmicutes, Actinobacteria, Bacteroidetes, Proteobacteria, and Verrucomicrobia were the dominant phyla in the HUA group , the phylum Proteobacteria and its derivative (Gammaproteobacteria), the order Enterobacteriales and its derivatives (Enterobacteriaceae and Shigella), the class Erysipelotrichi and its derivatives , the family Streptococcaceae and its derivative (Streptococcus), and the order Lactobacillales and its derivatives (Lactobacillaceae and Lactobacillus) were higher in the HUA patients. Conversely, the phylum Verrucomicrobia and its derivatives , the phylum Actinobacteria and its derivatives , and the family Ruminococcaceae and its derivative (Ruminococcus) were lower in the HUA patients.To determine the specific gut microbes related to HUA, we used linear discriminant analysis (LDA) effect size (LEfSe) to screen 186 gut microbial species. To develop a HUA diagnostic model using gut microbial biomarkers, we randomly divided (2:1 ratio) 107 participants (from the HUA and control groups) into the development and validation groups. Subsequently, we performed a 10-fold cross-validation of the random forest model in the development group, and 12 gut microbial biomarkers were identified as the optimum parameter set Table S2The clinical model was constructed using three clinical factors , and these factors were then also used in the combined model. These three clinical factors were selected using univariate regression and ROC curves (with AUCs), which identified 11 predictive clinical factors Table 3,In the development group, the combined model  were enriched in gout patients, while Faecalibacterium, Coprococcus, and Ruminococcus were decreased. We used high-throughput sequencing of the V3-V4 region of the 16S rDNA gene to characterize the microbiome in 168 fecal samples. The α diversity decreased in LSU and HUA patients compared to controls , genus Shigella, family Erysipelotrichaceae, and genus Streptococcus , and autoimmune diseases, such as systemic lupus erythematosus , were significantly reduced . These results suggested that the microbial biomarker model might be useful for the early diagnosis of HUA.Subsequently, we used a random forest model to identify 12 gut microbial biomarkers as the optimal parameter set for predicting HUA. We then used the POD index of the 12 microbial biomarkers to predict HUA. This index had strong predictive ability in both the development and validation groups , discrimination , and calibration results  for predicting HUA.There are several limitations to this study. First, although we developed a combined model that involved gut microbial biomarkers, the specific functions of these biomarkers remain unclear. Second, we only used 16S rDNA sequencing of DNA from stool samples, without assessing fecal metabolites or blood samples. Third, the sample size was relatively small, and external validation was not conducted. Multicenter studies involving different regions/countries are needed to verify the combination model.In conclusion, we first found that there were distinct gut microbiomes among participants with different serum uric acid levels. The gut microbial diversity decreased in LSU and HUA patients compared to controls, especially in HUA patients. Therefore, we developed a diagnostic model by combining clinical factors and gut microbial biomarkers that has practical clinical value for predicting HUA.The original contributions presented in the study are publicly available. This data can be found here: NCBI repository, accession number PRJNA869365.The studies involving human participants were reviewed and approved by The Medical Ethics Committee of the First Affiliated Hospital of Xinjiang Medical University(No. K202105-08). The patients/Participants provided their written informed consent to participate in this study.(I) Conception and design: ML, WC, YS. (II) Administrative support: YS, MK,YC, JL. (III) Provision of study materials or patients: YH, SY, YM. (IV) Collection and assembly of data: ML, TT, WX. (V) Data analysis and interpretation: WC, RL, BZ. (VI) Manuscript writing: all authors. (VII) Final approval of manuscript: all authors. All authors contributed to the article and approved the submitted version.This study was funded by the National Natural Science Foundation of China (No.81960169 and 81760169), the Natural Science Foundation of the Xinjiang Uygur Autonomous Region (No.2019D01C219 and 2021D01C275), the Project of Scientific Research Program for Universities in Xinjiang Uygur Autonomous Region (No.XJEDU2021Y054), the Postgraduate Research Innovation Project in Xinjiang Uygur Autonomous Region (No.XJ2021G228) the Science and Technology Plan Project in Xinjiang Karamay City (20212022hjcxrc0060).The authors are grateful to all the participants.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. 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An increasing prevalence of cognitive disorders warrants comprehensive systematic reviews on the effect of diet on cognitive health. Studies have suggested that the Mediterranean (MeDi) diet has protective effects against metabolic diseases. However, comprehensive systematic reviews on the effect of the MeDi diet on the cognitive decline are limited. We investigated whether adherence to the MeDi diet could lower the risk of the cognitive disorder or improve cognitive function in older adults.In this systematic review and meta-analysis, PubMed, Web of Science, PsycINFO, Scopus, and Cochrane databases were searched from inception to June 2021. Cohort studies and randomized controlled trials (RCTs) were included. The effect sizes were estimated as log risk ratios and standard mean differences (SMDs) with 95% confidence intervals (CIs). The Newcastle–Ottawa score and Cochrane Collaboration’s tool were used to assess the risk of bias in cohort studies and RCTs, respectively.Of the 1,687 screened studies, 31 cohort studies and five RCTs met the eligibility criteria for qualitative analysis; 26 cohort studies and two RCTs were included in the meta-analysis. In the cohort studies, high adherence to the MeDi diet was associated with lower risk of mild cognitive impairment (MCI) [risk ratio (RR) = 0.75 (0.66–0.86)], and Alzheimer’s disease (AD) [RR = 0.71 (0.56–0.89)]. In the RCTs, high adherence to the MeDi diet was associated with better episodic [SMD = 0.20 (0.09–0.30)] and working memories [SMD = 0.17 (0.01–0.32)] than lowest group.Adherence to the MeDi diet may reduce the risk of MCI and AD. However, other associations with cognitive outcomes  remain open to interpretation. Overall, the MeDi diet is recommended to prevent or delay cognitive disorders and improve cognitive function. Further, long-term RCTs are warranted to strengthen the evidence.https://www.crd.york.ac.uk], identifier [CRD42021276801].[ Mild cognitive impairment (MCI) is defined as a cognitive decline greater than that expected for the age and education level of the individual while not interfering with activities of daily living . MCI is The Mediterranean (MeDi) diet is a dietary pattern that has been followed by the Mediterranean Basin countries since the early 1960s  and is mThe association between the MeDi diet and increased longevity and reduced mortality and morbidity from certain cancers and other nutrition-related diseases has been widely studied –12. HoweThis systematic review and meta-analysis followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines . A protoStudies were selected and included based on the following inclusion criteria:1.Studies that were published in English, with no restrictions on the study sample size or the participants’ age, sex, or health status.2.Studies that were RCTs or prospective observational studies and investigated the relationship between adherence to the MeDi diet and cognitive function  or the risk of cognitive disorders .3.If two studies used the same cohort database, both were included.The exclusion criteria were as follows:1.Studies that did not adhere to the MeDi diet. For example, studies with adherence to a particular national dietary pattern or a healthy eating index.2.Studies that included participants with cognitive disorders or abnormal cognitive functioning at baseline.3.Case-control studies, cross-sectional studies, systematic reviews, narrative reviews, conference reports, or letters.Two authors (JF and L-JT) independently extracted data using the same extraction method. In the case of a dispute, a third author (SS) helped reach a consensus. The data on the last name of the first author, publication year, the health status of participants, follow-up duration, baseline age, percentage of men, sample size, dietary assessment method, MeDi diet assessment method, cognitive assessment methods, cognitive domains measured, and results were extracted from cohort studies. For the RCTs, data on the last name of the first author, publication year, country, population selection, follow-up duration, intervention group, placebo group, dietary assessment methods, and the MeDi diet assessment method, the baseline age and number of participants, outcome test methods, and results were extracted. Two reviewers independently assessed cognitive disorders and cognitive function of cohort studies and cognitive function of RCTs. Cognitive disorders included MCI, dementia, and AD, which were based on the battery of neuropsychological test or diagnosis criteria. Cognitive function included attention, episodic memory, executive function, global cognition, processing speed, and working memory, which were tested by the Mini-Mental State Examination (MMSE) or other common cognitive function tests .Two independent reviewers evaluated the quality of the cohort studies and RCTs. The Newcastle–Ottawa score (NOS) was used to evaluate the quality of the prospective cohort studies . Scores We performed a meta-analysis on three cognitive disorders and six cognitive domains. From the cohort studies, we extracted risk ratios (RRs) [hazard ratio (HRs) or odds ratio (ORs)] with 95% confidence intervals (CIs) for cognitive disorders  and effect sizes and standard errors for cognitive function . Owing to the asymmetry of the RRs, these values were log-transformed (base 10) . From RCIf the study reported 95% CI instead of SD, we used the following formula:P value of < 0.05 was considered statistically significant. The heterogeneity test in this review was examined using the Cochran’s Q test and quantified using the I2 statistic. For medium and low heterogeneity (I2 of < 50%), fixed-effects models were used, while random-effects models were used for high heterogeneity (I2 of ≥ 75%)  , 32. Morf ≥ 75%) , 33, 34.f ≥ 75%) .A total of 1,687 studies in PubMed, Web of Science, PsycINFO, Scopus, and Cochrane databases were identified. Of these, 820 studies were excluded after searching the keywords and reviewing the studies by their titles to assess relevance and eligibility. The abstracts of 103 studies were reviewed, after which the full texts of 47 studies were assessed. After excluding irrelevant studies and including reviews and cross-sectional studies, 31 cohort studies and five RCTs were included in the qualitative assessment. Finally, 26 cohort studies and two RCTs that met the criteria were included in the meta-analysis .n = 25) were women dominant, with five studies including only women and three studies including only men (n = 13). The majority of studies used an FFQ to assess the MeDi diet (n = 26), and two of these studies used both an FFQ and a 24-h dietary recall to assess diets (n = 25), while 1 study used a 0–15 MeDi diet score, defined by Morris et al. (n = 19), which included tests on attention, language, memory, visual-spatial skills, and orientation. Owing to individual differences in research, studies used different cognitive function tests, including the DST, TICS, Benton Visual Retention Test (BVRT).In total, 31 cohort studies and five RCTs were included in the review. Characteristics of prospective studies and RCTs are summarized in only men , 41, 47.ss diets , 16. Amoss diets , 45. Mors et al. , 61 and s et al. , 56, 57.Five RCTs were eligible for inclusion, all of which had a parallel design and included cognitively stable participants –66. Of tn = 29), and only two studies had scores of 6 and were, thus, regarded as having a high risk of bias . No significant associations were found with episodic memory  or working memory .A forest plot revealed the relationship between adherence to the MeDi diet and three domains of cognitive function in 14 cohort studies . Pooled 2 = 63.7%, P = 0.002). Moreover, pooled results indicated that high adherence to the MeDi diet was not associated with reduced risk of dementia . The pooled analysis, however, indicated that the MeDi diet could reduce the risk of AD by 29% .The forest plot shown in P = 0.033; I2 = 11.8%, P = 0.339), episodic memory , and global cognition  as compared with the control group. On the contrary, the MeDi diet showed an adverse effect on attention  and was not associated with executive function and processing speed ; both parameters showed no between-study heterogeneity .Two RCTs examined the effects on cognitive function based on six types of cognitive domains . The pooSubgroup and meta-regression analyses were performed in the cohort studies on the following covariates: study location, study published year, duration of follow-up, dietary intake assessment method, and study quality. However, owing to the limited number of studies (<10), the meta-regression was only conducted for global cognition and MCI risk , 5.P < 0.000; 2 = 0.0%). Pooled results of meta regression analyses revealed that study location, study published year, and duration of follow-up affect heterogeneity (P < 0.05) in terms of the MeDi diet and MCI risk, whereas the exposure assessment method and study quality do not affect heterogeneity , while high adherence to the MeDi diet was associated with lower risk of MCI .Regarding the relationship between the MeDi diet and global cognition, no covariates were found to affect heterogeneity except for the dietary assessment method (2 = 8.4%) and studies with follow up duration < 5 years without heterogeneity . A funnel plot of the relationship between the MeDi diet score and MCI risk in cohort studies was designed .Owing to the limitations in evidence (requiring more than 10 studies), publication bias was only investigated for cohort studies that analyzed the associations between the MeDi diet and global cognition and MCI. No publication bias was found  among healthy older adults . Their cIn 2021, a meta-analysis indicated that the results on the relationship between the MeDi diet and cognitive disorders were similar to those in our study. In particular, high adherence to the MeDi diet was beneficial to lower the risk of MCI and AD . The SpaRegarding the relationship between the MeDi diet and cognitive function in RCTs, the earliest meta-analysis of RCTs on this topic was presented by Loughrey et al. in 2017. They showed that high adherence to the MeDi diet could strengthen delayed recall, global cognition, and working memory, but no such association with attention was found . In 2018Of note, the pooled results of the included cohort studies and RCTs in our study were not the same, which may have been due to the insufficient number of included studies. Second, differences in the assessment of the MeDi diet also led to differences in the results. Third, the follow-up period was extremely short, as the RCT conducted by Knight et al. lasted for only 6 months , while cThe strength of this paper primarily lies in the following four factors: First, only cohort studies and RCTs were included in this review, and the results were discussed and analyzed separately. Second, this review strictly followed the PRISMA guidelines in the review process, and each step was carefully checked and examined. Third, a meta-regression analysis was conducted to determine the source of heterogeneity. Finally, when performing data extraction, we attempted to contact the authors to obtain accurate raw data. However, there were also limitations to our study. First, the MeDi diet assessment scores and cognitive function testing methods were different, which may have caused bias in the results. Additionally, differences in the dietary assessment methods may also limit comparability and increase error. Third, the follow-up duration of some cohort studies may have been too short to account for changes in cognitive function. Finally, we could not control for dietary differences due to regional variations. Although all studies adhered to the MeDi diet, it was thought that it would be easier and more effective for people from MeDi regions to follow the MeDi diet than for people in other regions.In summary, this review provided significant evidence that adherence to the MeDi diet could lower the risk of MCI and AD, whereas adherence to the MeDi diet was not related to dementia and other specific cognitive function domains  in the cohort studies. Across the RCTs, high adherence to the MeDi diet was positively associated with global cognition, working memory, and episodic memory. However, a negative association between the MeDi diet and attention was found. Overall, the MeDi diet is recommended to prevent or delay cognitive disorders and improve cognitive function. These results reinforce further clinical trials on the association between the MeDi diet and cognitive health, with longer follow-up time, especially on attention. Besides that, studies focus on cooking methods, cooking frequency in the MeDi diet was suggested to conduct as well.The original contributions presented in this study are included in the article/JF and L-JT: literature review and data extraction, data synthesis and statistical analysis, manuscript drafting. SS and JL: manuscript critical revision. All authors approved the final version to be submitted.


Several studies have investigated the value of the systemic immune-inflammation index (SII) for predicting cardiovascular disease (CVD), but the results were inconsistent. Therefore, a meta-analysis and systematic review were conducted to assess the correlation between SII and risk of CVD.Two investigators systematically searched PubMed, Embase, Web of Science, Cochrane library, and CINAHL databases to identify all studies that examined the association between SII levels and CVD. The risk estimates of CVD for people with high SII compared to those with low SII levels and the weighted mean difference (WMD) between the CVD and control groups were pooled using fixed- or random-effects models based on the heterogeneity test. We used the Newcastle-Ottawa Scale to assess the risk of bias in eligible studies, and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system was applied to rate the certainty of evidence.P < 0.001). This increased risk could be observed in almost all CVD subtypes, including ischemic stroke , hemorrhagic stroke , myocardial infarction , and peripheral arterial disease . There were no significant but still similar trends in venous thrombosis , cerebral small vessel disease , and acute coronary syndrome . Furthermore, the pooled results showed that SII levels at the onset of CVD were significantly higher than that in the general population , which was consistent across different CVD subtypes. The GRADE assessment suggested that the quality of current evidence from observational studies was low or very low.A total of 13 studies with 152,996 participants were included for analysis. The overall pooled results showed that higher SII was significantly associated with an increased risk of CVD  and cardiovascular diseases (CVD). ApprStroke and ischemic heart disease are two major diseases that contribute to the burden of CVD and cause of disability-adjusted life years , and theConsidering the importance of CVD risk identification and early intervention, some studies have explored the association between SII and risk of CVD, but no consistent conclusions have been reached. Therefore, we conducted a meta-analysis and systematic review to comprehensively examine the value of SII as an inexpensive and accessible indicator for predicting the risk of different CVD.This study was reported based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines . The proTwo investigators (ZY and RX) searched the PubMed, Embase, Web of Science, Cochrane library, and CINAHL databases for relevant studies published from database inception to 30 September 2021, using search strategies formed by Medical Subject Headings combined with synonyms; the search was updated on 10 June 2022. In addition to the items for “cardiovascular disease,” some common specific CVD types, such as coronary artery disease, cerebrovascular accident, heart infarction, vein thrombosis, and peripheral vascular disease, were also added to the search formula. The detailed search strategy for each data item is presented in According to the PICOS criteria defining the research questions, studies would be included if: (a) the study design was comparative, either the cohort or case-control study; (b) the study subjects are humans, with no restrictions on demographic characteristics, such as age, gender, or ethnicity; (c) for cohort studies, the population is divided into low-SII and high-SII level cohorts, and case-control studies should consist of CVD and non-CVD groups; (d) the correlation between different SII levels and CVD risk was assessed; risk ratios (RRs), odd ratios (ORs), or hazard ratios (HRs) were reported as effect sizes for this correlation, or sufficient data were provided to calculate these effect sizes. In addition, case-control studies that compared SII values between the non-CVD controls and CVD cases at the onset of cardiovascular events were also considered.Commentaries, editorials, reviews, cellular and animal model experiments, reviews, expert opinion, meta-analyses, conference abstracts, or studies with duplicate and clearly problematic data were excluded.Two authors (ZY and JW) screened the identified studies according to the inclusion and exclusion criteria. The retrieved records were preliminary screened by browsing titles and abstracts, and potentially eligible studies were read in full. Reasons for study exclusion were recorded and cross-checked. Any inconsistencies were resolved by consensus of all authors.The quality of eligible studies was assessed by the Newcastle-Ottawa Scale (NOS) in terms of selection, comparability, and outcome/exposure. A study with an NOS score of <7 was considered to be a low-quality study; otherwise, it was considered to be at low risk of bias. We used the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system to evaluate the certainty of the evidence, mainly regarding study design, risk of bias, directness of the evidence, consistency and precision of effect estimates, publication bias, large effect, plausible confounding, and dose-response gradient , 26. EviFor eligible studies, one investigator (XL) extracted the data and another investigator (ZY) checked the accuracy. The following information was recorded: first author, publication year, study area, sample size, age, study design, population source, study period, cardiovascular events, SII cutoff, method of cutoff determination, adjusted/matched confounding factors, follow-up time, and effect size.Q-test and Higgins’ I2 statistics were used to assess heterogeneity between published studies. Heterogeneity was considered significant when P < 0.05 or I2 > 50%, in which case the random-effects model was used; otherwise, results from the fixed-effects model were reported. The sensitivity of the analyses was checked by excluding one study at a time and then combining the remaining studies; we also performed a stratified analysis based on region and sample size. Egger’s and Begg’s tests were used to quantitatively assess the risk of publication bias. Data analysis was completed using Stata MP/16.0 ; all P-values were two-tailed and P < 0.05 was considered statistically significant.The pooled HRs and corresponding 95%CI were calculated as the measure of the correlation between SII and CVD risk. In addition, we calculated the weighted mean difference (WMD) of SII values between the CVD and control groups to further validate the correlation. When the median, maximum, minimum, and/or quartiles of SII were provided in the original study, we used the method proposed by Wan et al.  to estimThe pre-developed search strategy identified 2,664 records from PubMed, Embase, Web of Science, Cochrane library, and CINAHL databases. Based on the inclusion and exclusion criteria, a total of 13 studies were eligible for analysis –40. The Ten studies had NOS scores between 7 and 9, indicating low risk of bias based on NOS scale. Three studies had NOS scores of 6, and the main risk of bias was a lack of comparability due to not adjusting for confounding factors .2I = 90.8%, P < 0.001), so a random-effects model was applied; the overall pooled result showed that higher SII was significantly associated with an increased risk of CVD  (P = 0.233), coronary heart disease , and venous thrombosis , there was a consistent statistical significance for the risk of ischemic stroke , hemorrhagic stroke , myocardial infarction , and peripheral arterial disease  , and the pooled WMD was 355.2   . Subgrou= 0.001) . Further= 0.001) , 36–39, < 0.001) , furtherThe robustness of the combined results was assessed by excluding one study at a time to observe its impact on the results. As shown in P-values for Begg’s and Egger’s tests were 1.000 and 0.781, respectively, indicating a low risk of publication bias and small study effects.The The GRADE evidence profile table was generated with Guideline Development Tool (GRADEpro). Due to concerns over the vulnerability of observational studies to selection bias, the certainty of the evidence was initially rated as low quality for all endpoints, with coronary heart disease, stroke, and venous thrombosis downgraded one level to very low because of the potential risk of bias and/or inconsistency .To the best of our knowledge, this is the first study to focus on examining the association between SII and CVD risk. SII is a new inflammatory index based on platelet, neutrophil, and lymphocyte counts that reflects the host’s inflammatory and immune status. We found a significantly higher risk of CVD in people with high SII levels; this risk can be observed in almost every type of CVD. SII values were also significantly increased at the onset of various CVD. These findings suggest that SII may serve as an indicator to identify people at high risk of CVD and contribute to early diagnosis. However, due to the nature of observational studies, the quality of the current evidence is rated as low or very low.Cardiovascular disease encompasses a wide range of diseases with diverse and non-specific clinical presentations, making it easy to delay diagnosis and misdiagnosis, which leads to deterioration of the patient’s condition. Therefore, exploring a simple and widely available index to predict CVD is crucial. A large body of evidence suggests that chronic inflammation plays a key role in the pathogenesis of CVD –43. SpecP < 0.001). This means that in patients with unexplained headache and a normal plain CT, SII can help clinicians to quickly infer cerebral venous thrombosis and determine its severity and the necessity for immediate MRI/MRV confirmation, which can help to shorten the time between symptom onset and diagnosis and reduce misdiagnosis . Liu et al.  found thiagnosis . Furtheriagnosis  found thiagnosis  found a iagnosis .In addition to the correlation with CVD risk, SII has been found to predict the severity, complications, and mortality of CVD. For example, Zhang et al.  found thThe SII reflects a significant association of the host’s inflammatory and immune status with the risk of CVD. People with elevated SII on physical examinations may be recommended to adopt a lifestyle that can reduce inflammation, such as smoking cessation, weight control, reasonable emotional regulation, reduced sedentary behavior, regular exercise and rest, and reduction of saturated fat and refined carbohydrate content in the diet –57. MoreThe main limitation of this study is the small number of studies in some CVD subtypes resulting in conservative 95%CI. For example, for venous thrombosis, although a strong correlation was found, it was not significant, which may be due to insufficient statistical power. Second, populations outside of China are relatively underrepresented, and more studies from other geodemographic settings are necessary to examine possible regional specificities. Third, although Egger’s and Begg’s tests did not show significance, small study effects may still be present; studies with smaller sample sizes seemed to tend to report stronger correlations. Fourth, the limited data did not support a more detailed stratified analysis to identify populations that would benefit more from SII indicators. Furthermore, current studies on the association between SII and CVD risk used different SII cutoff values, which need to be standardized before SII can be widely used.In conclusion, our study indicated that SII may be a potential predictor of CVD. Healthcare providers need to be concerned about CVD risk in people with high SII and appropriate interventions may be needed. Due to the nature of observational studies, the quality of the evidence was graded from low to very low, which means that further research on the subject is necessary to draw solid conclusions. In addition, future studies should further determine the optimal cutoff value, characterize the benefited population, and investigate whether SII can be used in conjunction with other known CVD risk factors to build an accurate CVD risk assessment system.The original contributions presented in this study are included in the article/ZS and ML: conception, design, and critical revision of the manuscript. ZY, XL, JW, and RX: database search, literature review, and data extraction. XL and TH: statistical analysis. ZY, TH, XL, JW, and RX: drafting of the manuscript. All authors contributed to the article and approved the submitted version.


ACE, AGT, EDN1, EPO, FLT4, GREM1, IL1B, IL6, IL10, IL12RB1, NOS3, TGFB1, IGF2/INS/TH cluster, and VEGFA were highlighted as the key genetic components driving the fibrosis process in DN. The present systematic review and meta-analysis indicate, as key players of fibrosis in DN, sixteen genes. However, the results should be interpreted with caution because the number of studies was relatively small.Renal fibrosis (RF) constitutes the common end-point of all kinds of chronic kidney disease (CKD), regardless of the initial cause of disease. The aim of the present study was to identify the key players of fibrosis in the context of diabetic nephropathy (DN). A systematic review and meta-analysis of all available genetic association studies regarding the genes that are included in signaling pathways related to RF were performed. The evaluated studies were published in English and they were included in PubMed and the GWAS Catalog. After an extensive literature review and search of the Kyoto Encyclopedia of Genes and Genomes (KEGG) database, eight signaling pathways related to RF were selected and all available genetic association studies of these genes were meta-analyzed.  Diabetic nephropathy (DN) is a multifactorial condition that involves both metabolic and hemodynamic factors, but clear evidence  also indicates that the genetic profile of individuals plays a major role ,2,3. In Among the histological lesions that occur in DN ,6, renalIt is noteworthy that, although fibrosis is considered a detrimental condition, recent studies suggest a protective role of this process, because it helps the maintenance of crosstalk with injured proximal tubular cells supporting their regeneration . In autoGiven the undoubtedly genetic involvement in the course of DN, many genetic studies, such as linkage scans and genetic association studies (GAS), as well as meta-analyses of these studies, have been published ,14,15,16In order to identify the key players of fibrosis in the context of DN, we performed a systematic review and meta-analysis of all available genetic association studies regarding genes that are involved in signaling pathways related to RF. In this study, we included all available genetic association studies regarding fibrosis-related genes that have been published within a time period of 35 months since our field synopsis of all available genetic association studies regarding DN  and presIn an effort to decipher the key genetic components of the RF process, we performed a systematic review and meta-analysis of eight signaling pathways that are closely related to RF. The eight pathways were selected after a literature review and after a search of the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. The included pathways were the ACE pathway, the Relaxin pathway, the Wnt signaling pathway, the MAPK signaling pathway, the PI3KC signaling pathway, the TGFB1 signaling pathway, the NOTCH signaling pathway, and the JAK signaling pathway . The ovehttp://www.genome.gov/gwastudies/) (accessed on 11 June 2022) was conducted, and the inclusion and exclusion criteria and data extraction were as previously described [A literature search of PubMed and the GWAS Catalog (escribed . More spescribed .p < 0.10) and its extent was assessed with the I2 statistic [The genetic association between each polymorphism and DN was assessed using the generalized odds ratio (ORG) ,25. The tatistic ,28.We also examined if controls confronted with Hardy–Weinberg equilibrium (HWE) predicted genotypes using Fisher’s exact test for each study that provided genotype counts. We also tested for the ‘small-study effect’ with the Egger test .The literature search of both PubMed and the GWAS Catalog retrieved 5058 papers after the exclusion of duplicate studies, whereas, in the meta-analysis, 180 articles were included. When an article provided data for different populations, each population was considered as a different study. Among the 884 different genes that were involved in eight pathways related to fibrosis, 134 genetic variants located in 45 different genes were meta-analyzed. In comparison with our previous study [ACE), angiotensinogen (AGT), erythropoietin (EPO), gremlin 1, DAN family BMP antagonist (GREM1), interleukin 1 beta (IL1B), interleukin 6 (IL6), interleukin 10 (IL10), nitric oxide synthase 3 (NOS3), and transforming growth factor beta 1 (TGFB1). In meta-analyses based on genotype counts, statistically significant results were reported for angiotensin I-converting enzyme (ACE I/D polymorphism was significantly associated with DN with a pooled ORG of 1.22 (95% CI 1.10–1.35), the AGT M235T variant showed significant results with a pooled ORG of 1.21 (95% CI 1.01–1.45), EPO rs1617640 was significantly associated with DN with a pooled ORG of 1.64 (95% CI 1.43–1.89), GREM1 rs1129456 was associated with DN with a pooled ORG of 1.55 (95% CI 1.23–1.94), IL1B -511C > T provided significant results with a pooled ORG of 1.66 (95% CI 1.38–2.01), IL10 -1082A > G was also associated with DN with a pooled ORG of 1.23 (95% CI 1.01–1.49), and three variants in NOS3 gene  produced significant results with pooled ORG values of 1.21 (95% CI 1.08–1.36), 1.19 (95% CI 0.98–1.44), and 1.47 (1.11–1.95), respectively. More specifically, in comparison with diseased controls versus cases, the ACE I/D polymorphism was significantly associated with DN with a pooled ORG of 1.24 (95% CI 1.02–1.52), three variants of the NOS3 gene  provided significant results with pooled ORG values of 1.42 (95% CI 1.13–1.77), 1.64 (95% CI 1.21–2.22), 1.52 (95% CI 1.12–2.06), respectively, and TGFB1 T869C was also associated with DN with a pooled ORG value of 1.73 (95% CI 1.46–2.04).When healthy controls were compared with cases, the IL6 rs1800795 was significantly associated with DN with a pooled ORG of 1.44 (95% CI 1.10–1.89), and three variants of the NOS3 gene  gave significant results, with pooled ORG values of 1.29 (95% CI 1.17–1.43), 1.28 (95% CI 1.05–1.56), and 1.30 (95% CI 1.04–1.63), respectively.In a comparison of healthy controls versus diseased controls versus cases, EDN1), fms-related receptor tyrosine kinase 4 (FLT4), insulin-like growth factor 2/insulin/tyrosine hydroxylase cluster (IGF2/INS/TH cluster), interleukin 12 receptor subunit beta 1 (IL12RB1), and vascular endothelial growth factor A (VEGFA).In meta-analyses based on allele counts, significant associations were reported for endothelin 1 , FLT4 rs2242221 produced significant results with a pooled OR of 1.14 (95% CI 1.01–1.29), two variants in the IGF2/INS/TH cluster, rs1004446 and rs4320932, were also associated with DN, with pooled OR values of 1.16 (95% CI 1.03–1.31) and 0.84 (95% CI 0.73–0.96), respectively, and VEGFA rs2146323 also produced significant results, with a pooled OR of 0.85 (95% CI 0.76–0.95). In a comparison of healthy controls versus cases, only one variant in IL12RB1 (rs372889) was associated with DN, with a pooled OR value of 1.24 (95% CI 1.13–1.37). More specifically, in a comparison of diseased controls versus cases, ACE, AGT, EDN1, EPO, FLT4, GREM1, IL1B, IL6, IL10, IL12RB1, NOS3, TGFB1, IGF2/INS/TH cluster, and VEGFA) produced significant results in all meta-analyses.To the best of our knowledge, this review constitutes the most comprehensive study of the genetic variants that are related to fibrosis in the context of DN. This study is an extension of our previous work in the field of the genetic epidemiology of DN , but, foACE, AGT, EDN1, GREM1, IL1B, IL6, and TGFB1, whereas some other genes are known for their anti-fibrotic effects, such as EPO and NOS3. The statistically significant contribution of IL12RB1 and TH constitutes a novel finding, as there are no available experimental results to clarify their contribution to fibrosis.The present systematic review confirmed the statistical significance of genes that are well known to have fibrotic effects, such as ACE and AGT constitute members of the renin–angiotensin system (RAS), but this finding is no surprise because RAS inhibitors also have antifibrotic effects [More specifically,  effects . Many li effects . In addi effects . TGF-β i effects , suggest effects .IL12RB1, to the best of our knowledge, this is a novel finding as no previous studies have found any association of IL12RB1 with kidney fibrosis.Regarding the role of the innate proinflammatory cytokine IL1B, it has been reported that it induces a metabolic switch from oxidative phosphorylation to glycolysis in kidney stromal cells (SCs), promoting proximal tubule damage and fibrosis . IncreaseNOS and ApoE genes accelerates kidney fibrosis and senescence after injury [eNOS) 4b/a gene polymorphism and renal interstitial fibrosis in patients with DN demonstrated that the frequency of eNOS4bb in DN renal interstitial patients was lower than that in non-nephropathy diabetic patients and normal controls [EDN1, it has been found that the endothelin receptors in renal interstitial cells do not contribute to the development of fibrosis during experimental kidney disease [EPO gene, it has been found that erythropoietin attenuates renal interstitial fibrosis via the inhibition of fibrocyte accumulation [Grem1), which is an antagonist of bone morphogenetic proteins, plays a key role in kidney development and renal fibrosis, and a previous study demonstrated that its levels are increased in many diseases associated with fibrosis [FLT4, a tyrosine kinase receptor for VEGFC and VEGFD, is involved in lymphangiogenesis, which is a condition that develops during the progression of fibrosis, indicating a fibrotic effect of this factor [A previous study reported that the disruption of r injury , indicatcontrols . Regardi disease . However disease . Regardimulation . Gremlinfibrosis . More sps factor .IGF2/INS/TH cluster, previous results have shown that IGF2 stimulates the differentiation into myofibroblasts that produce large amounts of collagen and other extracellular matrix proteins (ECM) [INS, a hormone that plays a key role in carbohydrate and lipid metabolism, it has been found that sodium–glucose cotransporter 2 (SGLT2) inhibitors suppressed kidney fibrosis in diabetic mice [TH, which is involved in tyrosine-to-dopamine conversion, there are no results regarding its involvement in kidney fibrosis. Finally, VEGFA, a growth factor essential for both physiological and pathological angiogenesis, can inhibit the expression of Smad3 and miR192, thereby suppressing TGF-β-induced EMT and improving renal fibrosis [Regarding the ns (ECM) . Regarditic mice . Regardifibrosis .ACE, IL1B, IL-6, and IL-10 are key mediators of MCs, and these genes have produced statistically significant results in the present systematic review and meta-analysis. The role of MCs in the fibrotic process is controversial, as studies in humans and in vitro data indicate a pro-fibrotic role of these cells, whereas animal studies have produced inconsistent results [Based on the statistically significant results of the present systematic review and meta-analysis, it should be noted that mast cells (MCs) are implicated in many fibrotic conditions ,48,49,50 results . The rea results , these c results . It has  results ,54, but  results ,56. One  results ,58,59,60ACE, AGT, EDN1, EPO, FLT4, GREM1, IL1B, IL6, IL10, IL12RB1, NOS3, TGFB1, IGF2/INS/TH cluster, and VEGFA). However, the results should be interpreted with caution because the number of studies in most meta-analyses is relatively small.In summary, the present systematic review and meta-analysis indicate, as key players of fibrosis in DN, sixteen genes (


Second primary cancer incidence is rising among breast cancer survivors. We examined the risks of non-breast second primaries, in combination and at specific cancer sites, through a systematic review and meta-analysis.We conducted a systematic search of PubMed, Embase, and Web of Science, seeking studies published by March 2022. We included studies that reported standardized incidence ratios (SIRs), with associated standard errors, assessing the combined risk of second non-breast primaries following breast cancer. We performed meta-analyses of combined second primary risks, stratifying by age, follow-up duration, and geographic region. We also assessed second primary risks at several specific sites, stratifying by age. The inverse variance method with DerSimonian–Laird estimators was used in all meta-analyses, assuming a random-effects model. Associated biases and study quality were evaluated using the Newcastle–Ottawa scale.I2: 99%). This varied by age: the estimate was 1.59 (95% CI 1.36–1.85) when breast cancer was diagnosed before age 50, which was significantly higher than in women first diagnosed at 50 or over . SPC risks were also significantly higher when based on Asian, rather than European, registries . There were significantly increased risks of second thyroid , corpus uteri , ovary , kidney , oesophagus , skin (melanoma) , blood (leukaemia) , lung , stomach  and bladder  primaries.One prospective and twenty-seven retrospective cohort studies were identified. SIRs for second non-breast primaries combined ranged from 0.84 to 1.84. The summary SIR estimate was 1.24 (95% CI 1.14–1.36, Breast cancer survivors are at significantly increased risk of second primaries at many sites. Risks are higher for those diagnosed with breast cancer before age 50 and in Asian breast cancer survivors compared to European breast cancer survivors. This study is limited by a lack of data on potentially confounding variables. The conclusions may inform clinical management decisions following breast cancer, although specific clinical recommendations lie outside the scope of this review.The online version contains supplementary material available at 10.1186/s13058-023-01610-x. Multiple studies have compared the risk of second primary cancers (SPCs) following a first breast cancer (BC) to the corresponding first cancer risks in the general population –33. AlthMost published studies to date drew their data from European or North American population-based cancer registries –31, 33, A systematic review of the latest published evidence on SPC risks is helpful in guiding clinical management following BC. This could lead to improvements in SPC prevention and early detection.In this review, we examine the latest evidence regarding the combined risks of developing SPCs following a first primary BC. We also evaluate the variability in SPC risks caused by confounding variables such as patient characteristics and demographic information. Finally, we identify which cancer sites may drive the combined risk of SPCs and quantify the magnitude of these site-specific risks.The exposure was the diagnosis of a primary BC. The outcome was the later diagnosis of a non-breast SPC. The measure of association was the standardized incidence ratio (SIR) comparing the incidence of second non-breast primaries among BC survivors to the incidence of first non-breast primaries in the general population.breast primaries following a first BC to differ between the SEER and IARC/IACR guidelines and counts of all other primaries to agree very closely  OR “breast cancer”) AND  AND risk(TS = ((“breast cancer” OR “breast neoplasm”) AND (“second cancer” or “second primary”) AND risk)) OR (AB = ((“breast cancer” OR “breast neoplasm”) AND (“second cancer” or “second primary”) AND risk))To be included in the review, a study had to provide all information needed to extract a SIR and associated standard error evaluating the combined risk of non-breast SPCs in female BC survivors. It also had to take clearly described steps to discern SPCs from recurrences or metastases of the first BC, use data predominantly on those aged 15 and above at BC diagnosis, and be written in English.A study would be excluded if it evaluated SPC risks only in survivors of a non-invasive BC or only following a specific treatment of the first BC. Studies would also be excluded if data on third or subsequent primaries could not be excluded from their SPC risk estimates or if their data overlapped entirely with another accepted study.Studies with data that partly but not fully overlapped were included in the review. In this case, the study with a greater sample size was the only one included in any meta-analyses. If this could not be established, the study including the most recent data was the one included.There is a particularly close data link between the Swedish Family Cancer Database and the Swedish national cancer registry . The samTitle and abstract screening was performed by two authors as part of an independent double-screening process. Conflicts regarding twelve studies were resolved by another author. We closely read the full text, swept the bibliographies, and whenever applicable searched the PubMed “cited by” sections of each the studies that passed the title and abstract screening in search of additional studies.We assumed there would be some between-study variance in SIRs not attributable to sampling error, and therefore assumed a random-effects model in all meta-analyses , using tQ [I2 statistic [Q is the sum of squared differences between the estimate of the pooled effect size and the effect sizes reported by each study, weighted by the inverse variances of the studies [I2 statistic is the percentage by which the observed value of Cochran’s Q exceeds the value expected under the null hypothesis of no between-study heterogeneity [We firstly performed an unstratified meta-analysis. We quantified the heterogeneity  in Q  and the tatistic , 51. Coc studies . The I2 ogeneity .Q to decrease by over 10% once they were removed from the unstratified meta-analysis. We also defined outlier studies to be studies which reported SIRs with 95% confidence intervals that lay wholly outside the confidence interval around the summary SIR generated by the unstratified meta-analysis [We also performed leave-one-out analyses to identify which studies were the main drivers of heterogeneity , which wanalysis . We thenanalysis .We also performed further meta-analyses stratifying on (1) age at BC diagnosis—under 50 years and 50 years or above. Data on those diagnosed before age 56 and at age 56 or over were, respectively, included in the younger and older strata if no stratification at 50 was provided, (2) follow-up time duration following BC diagnosis—under 5 years or 5 years and over. We also performed a second meta-analysis stratifying at 10 years, (3) geographic region—the continent of the data centre  used in a particular study.Q statistic, by considering each stratum as a subgroup, and by comparing the resulting statistic to a chi-squared distribution [We evaluated for differences in risks by age, follow-up duration, and geographic region using the Cochran’s ribution .Q and I2 statistics in each stratum for each stratified meta-analysis, to assess if a particular risk factor explained some of the heterogeneity in the unstratified analysis of non-breast SPC risks.We also examined the Cochran’s We extracted SIRs that quantified SPC risks at specific sites, together with associated standard errors, from the studies included in the unstratified meta-analysis. We then estimated summary SIRs for SPC risks at these sites by conducting meta-analyses of the relevant site-specific SIRs. This was done to elucidate which cancer sites were driving the combined risks of all non-breast SPCs. We first examined site-specific risks for all ages. We then stratified by age at BC diagnosis, using the same stratification points as in the analyses of combined non-breast primary risks. These analyses were performed for each of the 20 non-breast cancer sites with the highest incidence among women worldwide in 2020, excluding non-melanoma skin cancer and excluding oral cavity and lip cancer due to SPC risks at this site often being combined with other head and neck sites , 23, 33.p value of under 0.05 was observed.Forest plots were generated as a visual aid to accompany each meta-analysis. We evaluated the methodological quality of each study using the Newcastle–Ottawa scale (NOS) , as recoIn total, 112 studies were accepted for review at the full-text level after passing the title and abstract screening stage. Sixty-five of these were selected from the 2011 studies returned after the database searches. Thirty-eight of the 112 studies were found following sweeps of the bibliographies of 69 studies: the 65 studies previously mentioned, and 4 additional studies which only failed the title and abstract sweeping due to exclusively examining male BC survivors. We identified the final 9 of the 112 studies after sweeping the “cited by” section of PubMed for 66 of these 69 studies, as the remaining three studies –58 were All studies included were cohort studies, only one of which was prospective . Three sThe longest follow-up period was 57 years . The shoSix studies set minimum ages at first cancer diagnosis, at age 15 years , 16, 23 Fifteen studies excluded data on second primaries occurring within some given follow-up duration following the first BC diagnosis , 25, 26.All but one study  gave sitThe reported SIRs ranged from 0.84  to 1.84 The characteristics of all 28 studies are detailed in Table The unstratified meta-analysis consisted of nineteen studies , 27, 33.Q: 1839.32, I2: 99%, p < 0.001).The summary SIR was estimated as 1.24 , and there remained significant evidence for heterogeneity .Following leave-one-out analyses, we found the studies by Diab et al. , Odani eQ: 166.23, I2: 93%, p < 0.001).We identified 7 outlier studies , 19, 23.Examining a funnel plot and performing Egger’s test revealed no significant evidence of publication bias  for European studies vs. 1.03 (1.02–1.04) for North American studies, Q: 222.36, I2: 97%, p < 0.001) and for the European subgroup analysis . No significant evidence for heterogeneity was found in the North American subgroup analysis .Significant heterogeneity was found for the Asian subgroup analysis (p for difference: 0.005). There was also significant evidence that American BC survivors were at lower risks of SPCs compared to European BC survivors (p for difference: 0.027).There was significant evidence that Asian BC survivors had higher SPC risks in comparison with European BC survivors, for whom the largest amount of data was available .Eight studies were included in the age-stratified meta-analyses , 19, 33.Stratification of BC survivors by follow-up duration revealed no significant evidence for a difference in SPC risks. Full results may be seen in the Additional file Point estimates of summary SIRs estimating SPC risks unstratified by age at the nineteen examined sites ranged from 0.80 (for the brain and CNS) to 1.89 (for the thyroid). BC survivors were found to be at significantly lower risk of brain and CNS cancers , and there was a suggestion of decreased cervix uteri cancer risk . In contrast, there was significant evidence for elevated second primary bladder , corpus uteri , kidney , blood (leukaemia) , lung , skin (melanoma) , oesophagus , ovary , stomach , and thyroid  cancer risks following BC.We found BC survivors first diagnosed with BC at under age 50 to be at elevated risk of second primaries at the bladder , blood (leukaemia) , corpus uteri , kidney , lung , oesophagus , ovary , pancreas , skin (melanoma) , stomach , and thyroid .We found there to be significantly increased risks of second primaries at three sites in BC survivors diagnosed with BC at age 50 or over: the corpus uteri , the oesophagus , and the skin (melanoma) .p for difference: < 0.001). They were also at significantly increased risks of second primaries at the pancreas , p for difference: < 0.001), blood (leukaemia) , p for difference: 0.026), oesophagus , p for difference: < 0.001), ovary , p for difference < 0.001), stomach , p for difference < 0.001), and thyroid , p for difference < 0.001).BC survivors diagnosed with breast cancer before age 50 were at significantly increased risk of second primary lung cancer compared to BC survivors diagnosed with breast cancer at age 50 or over  for those aged over 50 at first BC diagnosis, Full results may be seen in Table In this review, we found significant evidence for elevated SPC risks among BC survivors, particularly when first diagnosed with BC at under age 50 or in Asian hospitals/registries. Risks of second primary bladder, kidney, blood, lung, skin (melanoma), oesophagus, ovary, stomach, thyroid, and corpus uteri cancers were significantly increased, whereas risks of brain and CNS and cervix uteri SPCs were significantly decreased.This review has several strengths. The studies were of high quality .To investigate whether the definition of SPC influences the results, we also performed a meta-analyses including only studies using IACR/IARC coding rules to identify second primaries , 27, 33.It is likely that including studies from three different continents contributed to heterogeneity, since SPC risks in these continents were found to vary significantly. Similarly, if ages at BC diagnoses varied widely between studies, then this would account for some of the heterogeneity, as younger age groups were found to be at significantly increased risk in comparison with those older. However, although heterogeneity was attenuated, it remained significant among Asian and European studies as well as in both younger age and older age groups, so these points cannot fully explain the observed heterogeneity.It is also possible that differences in the treatments administered between studies could affect SPC risks –62 and tIt is known that cancer survivors may be more prone to being diagnosed with second cancers simply due to increased surveillance for cancer development, rather than a genuine increase in risk compared to the general population. This is known as “detection bias”, and we cannot rule out that it may have affected some results in this review . HoweverIt is also possible that some of the observed variability in SIRs between studies could be due to differences in analytical methods and differences in the data quality control processes or the definition of second primary cancers used across registries. For example, Diab et al. calculated SIRs using the SEER database, a population-based data set of very high quality , 63 and Finally, although every effort was made to capture all relevant studies, it cannot be ruled out that some studies were not found or were excluded erroneously.This review adds to the previously published review  in severThe increased SPC risks could be partly due to treatment effects of the initial BC, such as the administration of hormonal therapy such as tamoxifen, or the administration of chemotherapy or radiotherapy –62, 65. BRCA1/2 have been found to be associated with risks of multiple primary cancers, including pancreatic and stomach cancers [BRCA1/2 are also associated with ovarian cancer risk [, as are pathogenic variants in PALB2 [RAD51C [RAD51D [Germline susceptibility to BC may also raise specific SPC risks . For exa cancers . Pathogecer risk , 77, as in PALB2 , RAD51C  [RAD51C , 80, and [RAD51D . Such ob [RAD51D , 83. The [RAD51D . Elevate [RAD51D ; for exa [RAD51D  and a re [RAD51D . GeneticIf germline susceptibility does increase SPC risk in female BC survivors, this may partly explain our finding of elevated SPC risks in women diagnosed with BC at under age 50 compared to those diagnosed when older, since genetic susceptibility to BC is associated with earlier BC diagnosis , 87. ThiThe decreased risks of blood (myeloma), brain and CNS, and liver SPCs among BC survivors aged 50 or over at first BC diagnosis may be explained by under-ascertainment of SPCs in older age groups . We alsoIn conclusion, this review found that the combined risks of second non-breast cancer following a first primary BC were significantly elevated. Female BC survivors aged under 50 at BC onset or who were from Asian registries/hospitals were found to be at higher risks than other groups. Finally, we found second cancers at the bladder, corpus uteri, kidney, blood, lung, skin (melanoma), oesophagus, ovary, stomach, and thyroid to notably contribute to the observed elevated SPC risks.The results may lead to increased awareness of the magnitudes and distribution by site of SPC risks following BC. They could also better inform cancer risk management, although specific recommendations would be beyond the scope of this review.Additional file 1. Additional File.


NOS3 gene polymorphisms and end-stage renal disease (ESRD). However, the results are still unclear and the mechanisms are not fully defined. As a result, we conducted a meta-analysis to examine the relationship between NOS3 gene polymorphism and ESRD in autosomal polycystic kidney disease (ADPKD) patients.Endothelial nitric oxide synthase (eNOS) genes have been implicated in renal hemodynamics as potent regulators of vascular tone and blood pressure. It has been linked to a reduction in plasma nitric oxide levels. Several studies have recently been conducted to investigate the role of NOS3 gene polymorphism and ESRD, relevant studies published between September 2002 and December 2020 were retrieved from the PubMed (Medline), EMBASE, Google Scholar, and Web of Science databases. The pooled odds ratio (OR) and 95 % confidence interval (CI) were calculated using a fixed-effect model. To assess the heterogeneity of studies, we used Cochrane’s Q test and the Higgins and Thompson I2 statistics.To assess the relationship between NOS3 gene polymorphisms significantly increased ESRD risk in ADPKD patients with 4a/b gene polymorphism . In addition, no significant association was found between the NOS3 894G>T (Glu298Asp) polymorphism and the risk of ESRD in ADPKD patients . There was no evidence of publication bias.Our meta-analysis of 13 studies showed that the presence of the two NOS3 intron 4a/b polymorphism plays a vital role in the increasing risk of ESRD in ADPKD patients.The findings of the current meta-analysis suggest that  Among all renal cystic diseases, ADPKD is genetically heterogeneous and affects all racial groups worldwide, associated with liver, cardiovascular, gastrointestinal and genital abnormalities, with an estimated frequency between 1:400 and 1:1,000. ADPKD may be caused by mutations in one of the two genes, namely polycystic kidney disease 1 (PKD1), mapped to 16p13.3, and polycystic kidney disease 2 (PKD2) gene on chromosome 4q21. The frequency of mutations of PKD1gene is much higher and the gene is responsible for 85% of ADPKD cases, while 15% is caused by the PKD2 gene. Additionally, elderly patients have more cases of PKD2 mutations than of PKD1 mutations. Renal disease involves hypertension, urinary tract infections (UTI), hematuria, renal pain, and renal insufficiency, and end-stage renal disease (ESRD) occurs in approximately 50% of ADPKD patients in their late forties.Renal cysts can have various etiologies, broadly classified into genetic and non-genetic disorders. The most common and widely accepted genetic cause of renal cystic disease in humans is autosomal dominant polycystic kidney disease (ADPKD), autosomal recessive polycystic kidney disease (ARPKD), and juvenile nephronophthisis, for which genes or chromosomal locations have been identified. NOS3 is a dimeric cellular signaling molecule with significant regulatory activities such as glomerular vasodilatation, which is essential for controlling the glomerular filtration rate (GFR). In this perspective, NOS3 in ADPKD was considered a possible candidate gene for ESRD. The NOS3 gene was mapped to a chromosome of 7q36 consisting of 26 exons. Several polymorphic variants have been associated to modified NO synthesis, including promoter-786 T > C, 894 G > T, and intron 4 variable tandem repeats a / b (VNTR) polymorphisms. Among these, the 27-base pair (bp) (VNTR) intron-4 of NOS3 is known to alter eNOS expression and cause impaired NO synthesis. The genotypes and haplotypes of NOS3 tagSNPs were not associated with the disease.ESRD is a multifactorial disease and has been shown to be more significant in many aspects of this genetic factor. Previous evidence has proven that impaired nitric oxide synthase 3 (NOS3) contributes to vascular endothelial dysfunction, and blood endothelial cells are suggested to play a vital role in the pathogenesis of ESRDNOS3 gene polymorphisms and ESRD in ADPKD, the findings were inconsistent. In view of the clinical heterogeneity of ADPKD, this study aimed to quantitatively summarize the association between NOS3 polymorphisms (894G>T intron 4 VNTR a / b polymorphism) and ESRD risk in ADPKD by conducting a comprehensive meta-analysis of all eligible case-control studies.Although many researchers examined the association between NOS3 gene polymorphism and ESRD were identified. All case-control studies considering the association in ADPKD patients published in English languages were selected and organized according to the PRISMA guidelines.Articles published between September 2002 to December 2020 on the associations of the NOS3”, “ESRD”, “intron 4 VNTR”, “meta-analysis”, “case-control”, “894G>T ”. The last search was carried out on 30 February 2021.A comprehensive search was conducted in electronic databases including PubMed (Medline), EMBASE, Google Scholar, and Web of Science with the combination of the following keywords and subheadings: “endothelial nitric oxide synthase”, “eNOS”, “NOS3 polymorphisms and risk of ESRD in ADPKD, (2) available full-text articles, (3) written in English, and (4) original data and complete genotype allele count for both the case and control groups were available. Studies were excluded if they (1) had overlapping/duplicate data, (2) had no control group, (3) did not have clear genotype data, and (4) were case reports and review articles. All information about the selection of studies in ADPKD patients with or without ESRD was arranged.To conduct a more robust meta-analysis, two authors collected data from all relevant articles independently. Our selection criteria were: (1) case-control studies on the association between NOS3 gene polymorphisms (894G>T and intron 4 VNTR) was assessed by the summary odds ratio (OR) and the 95% confidence interval (CI) in the dominant model. To assess the between-study heterogeneity, we used Q and I2 statistics in all studies. To assess the robustness of findings, sensitivity analysis was performed using a “leave-one-out” meta-analysis. Egger’s test and Begg’s funnel plot were used to assess publication bias. All statistical analyses were done using the Comprehensive Meta-analysis software. A P-value of <0.05 was considered statistically significant.The genotype data of case and control groups were recorded. The comparison group already included a selection, but NOS3 genotypes were not tested for Hardy-Weinberg equilibrium (HWE). The meta-analysis was carried out using the web tool MetaGenyo. For each study, the strength of association between ESRD risk in ADPKD and NOS3 894G>T and intron 4a/b polymorphisms and ESRD risk were excluded. Twenty-nine articles were fully reviewed, of which 9 papers with 520 ADPKD patients with ESRD and 563 ADPKD patients without ESRD for the NOS3 894G>T polymorphism and 5 papers with 185 ADPKD patients with ESRD and 223 ADPKD patients without ESRD for NOS3 intron 4a/b polymorphism that had sufficient data were included in the present meta-analysis. The process of selecting papers is depicted in Using the aforementioned search strategy, 82 articles were identified. From these, 22 duplicate and irrelevant articles were excluded. After reading the abstracts and titles, 31 articles that did not assess the association between NOS3 polymorphism variants and ESRD risk in ADPKD was assessed in a dominant model    . Howevert model) .NOS3 gene polymorphisms  showed significant heterogeneity. Sensitivity analyses were performed by excluding studies one at a time and conducted the analysis after each omission. There were no statistically significant differences in polymorphism data, indicating that the analysis was statistically reliable and consistent -dependent pathway. Besides, it has directly involved in the vascular endothelium, complex cellular interactions, and global inflammation-mediated cell activation. Generally, NO inhibits NaCl absorption along the nephron. Several studies have shown that NOS inhibitors such as nitro-L-arginine and NG-nitro-L-arginine methyl ester (L-NAME) have a tonic influence, especially on medullary circulation. Despite this, renal NO synthesis is involved in the acute and chronic regulation of sodium balance.The NO synthases (NOS) are a family of enzymes that catalyze the production of nitric oxide (NO) from L-arginine in vascular endothelial cells. Another study found that eNOS expression and eGFR were significantly higher in ADPKD patients without hypertension than in those with hypertension. This demonstrates that eNOS gene expression is independently predictive of hypertension in the ADPKD population.Hypertension is the most frequent complication in ADPKD patients, occurring in approximately 60% of the patients. Miyamoto et al. discovered that the 894G>T (Glu298Asp) missense variant was significantly associated with essential hypertension, suggesting a genetic susceptibility for essential hypertension. This mechanism has been shown to accelerate the progression of pre-existing kidney disease. Various studies have shown that NO negatively regulates the renin-angiotensin system by inhibiting ACE activity and AT1 receptors. The release of NO by endothelial cells plays a major role in regulating the local hemodynamics and systematic blood pressure. Decreased production of NO plays a major role in the progression of renal disease. A significant decrease in different isoforms of NOS in the cystic epithelium was observed during the growth of a renal cyst in Han: Sprague-Dawley (SPRD) polycystic rats. Several lines of evidence suggest that ADPKD is characterized by endothelial dysfunction caused by impaired NO release.In kidney disease, NO production is reduced by either a decrease in the enzyme substrate (L-arginine) or an increase in the bioavailability of the enzyme inhibitor asymmetric dimethylarginine (ADMA), which in turn reduces NO synthesis via a feedback mechanism. ADPKD patients with the 4a allele progressed to ESRD more slowly in Belgium and France, whereas Hellen’s patients from Greece and Cyprus progressed faster. However, some studies suggested that this locus was not linked with ESRD of different etiologies. The substitution of aspartic acid for glutamate affects the domain of the oxidase enzyme that serves as a binding site for BH4 and the amino acid L-arginine. The change causes an enzyme variation, making it more susceptible to proteolytic cleavage in position D238-P239. Further, it produces a shorter form of the enzyme, resulting in less NO production. However, the relationship between 894G>T polymorphism and the age of onset of ESRD in ADPKD patients also yielded inconsistent results. While the-786T>C (rs2070744) polymorphism has a functional effect, it is linked to the replication protein A1 (RPA1), which binds to the NOS3 promoter with high affinity when the C allele is present, resulting in reduced NOS3 transcription.Animal models and clinical trials have demonstrated the importance of NOS in polycystic kidney disease. Our findings were inconclusive in terms of ethnicity-specific associations between NOS3 gene polymorphisms and ESRD in ADPKD patients. This is possibly due to differences in the allele frequencies of the NOS3 gene among populations. Individual studies investigating the link between NOS3 polymorphisms and ESRD complications have also been conducted. Still, these studies may have been imbalanced due to the inability of individual components to identify the desired impact of these polymorphisms.No significant findings were observed regarding the promoter-786 T>C polymorphism with ESRD progression in patients with type 1 ADPKDNOS3 intron 4a/b polymorphism, but not the G894T polymorphism, seems to increase the risk of ESRD in ADPKD patients. More high-quality studies are needed to investigate the complexities of the associations between NOS3 gene polymorphisms and the therapeutic implications of ESRD in ADPKD patients.Certain limitations and biases of the study have to be considered and resutls should be interpreted with caution. Our meta-analysis indicated that the


Backgrounds and objectives: Chronic obstructive pulmonary disease (COPD) is a multifactorial disease under genetic control. We present a meta-analysis to examine the associations of vitamin D binding protein (VDBP) gene rs7041 polymorphism with the risk of COPD and changes in circulating 25OHD concentrations.Methods: A literature search, quality assessment, and data extraction were conducted independently by two investigators. Data are expressed as odds ratio (OR) or weighted mean difference (WMD) with a 95% confidence interval (CI). The inverse variance weighted method (IVW) in R (version 1.1.456) was applied to calculate the Mendelian randomization coefficient.Results: A total of 13 articles with 3,667 participants were meta-analyzed. The rs7041-GT genotype was associated with a 49% reduced COPD risk  compared to the rs7041-TT genotype. Carriers of the rs7041-GT genotype had significantly higher concentrations of circulating 25OHD than those with the rs7041-TT genotype . Under the assumptions of Mendelian randomization, and assuming a linear logistic relationship between circulating 25OHD and COPD, an inverse association was noted after using VDBP gene rs7041 polymorphism as an instrument . There was a low probability of publication bias.Conclusion: We observed significant associations of VDBP gene rs7041 polymorphism with the risk of COPD and changes in circulating 25OHD concentrations. Importantly, we found a causal relationship between genetically regulated 25OHD concentrations and COPD risk. Chronic obstructive pulmonary disease (COPD) places a major burden on individuals and public health systems . The GloVDBP).COPD is a multifactorial disease under genetic control . The herVDBP gene is localized in chromosome 4q11-q13; it has three commonly recognized haplotypes  and rs7041 polymorphisms are one of the most common non-synonymous single-nucleotide polymorphisms (SNPs) for the haplotypes  statement . The PRIA literature search was carried out in the three online databases  up March 10, 2022, including articles ahead of publication. The following keywords were used in searching: (“Vitamin D binding protein” OR “VDBP” OR “VDB” OR “DBP” OR “Gc-globulin” OR “Gc-globulin” OR “GC”) AND (“COPD” OR “chronic obstructive pulmonary disease”) AND (“polymorphism” OR “SNP” OR “variant” OR “variation” OR “mutation” OR “single nucleotide polymorphisms”).Two authors (MY and BP) completed the literature search independently, and any disagreement was solved by discussion. In addition, the references of major reviews or meta-analyses were also checked for potentially eligible articles that were not identified by the two authors.VDBP gene rs7041 polymorphism in COPD patients and controls or mean or median values of circulating vitamin D concentrations across rs7041 genotypes; 4) a clear definition of COPD [COPD is diagnosed by doctors or according to the Global Initiative for Chronic Obstructive Lung Disease (GOLD) or American Thoracic Society (ATS) guidelines]; and 5) a validated genotype assaying method. Moreover, in cases when more than one article was published using the same or part of the same sample of study participants, the article using the largest sample size was included.Articles eligible for inclusion in this meta-analysis must simultaneously meet the following criteria: 1) case-control design; 2) published in the English language; 3) providing genotype counts of Articles were excluded if any one of the following criteria was met: 1) published in form of a review, correspondence, comment, conference abstract, case report, case series, or clinical trial; 2) a clinical outcome other than COPD; and 3) the lack of a control group.1), FEV1 predicted ratio, forced vital capacity (FVC), FVC predicted ratio, and FEV1/FVC, if available.Data were extracted from each eligible article independently by two authors (MY and BP) according to a predefined template, covering the surname of the first author, year of publication, country where the study was performed, ethnicity, sample size, source of controls, matched condition, diagnosis criteria of COPD, genotype counts of rs7041 polymorphism between patients and controls, mean or median 25OHD concentrations across rs7041 genotypes in patients or controls or both, and baseline characteristics of study participants including age, gender, body mass index (BMI), percentage of smokers, smoking exposure (cigarette pack-years), smoking status, forced expiratory volume in 1 s (FEVVDBP gene rs7041 polymorphism with the risk of COPD. The weighted mean difference (WMD) and 95% CI were calculated to quantify the changes of circulating 25OHD concentrations between genotypes of this polymorphism in COPD patients or controls or both . The Hardy–Weinberg equilibrium for VDBP gene rs7041 polymorphism was calculated using the R package “GWASExactHW” (version 1.1.456), and p > 0.05 indicated no deviation from the Hardy–Weinberg equilibrium.STATA software version 14.1  was utilized in this meta-analysis. The weighted odds ratio (OR) and the 95% confidence interval (CI) were calculated to quantify the association of I-squared (I2). A larger I2 value is indicative of a higher probability of between-study heterogeneity. Significance for I2 was set at 50% ; homozygous genotype model (rs7041-GG vs. rs7041-TT); heterozygous genotype model (rs7041-GT vs. rs7041-TT); and dominant model (rs7041-GG + GT vs. rs7041-TT). This association was significant under the heterozygous genotype model and the dominant model, with the odds of having COPD being 0.51  and 0.68 , respectively; however, there was moderate evidence of heterogeneity between studies for both models, with a corresponding I2 value of 77.4% and 77.6%, respectively.As shown in VDBP gene rs7041 polymorphism with COPD was potentiated in Caucasians , in studies with matched patients and controls , in studies with doctor-diagnosed COPD , and adopting ATS criteria . Under the dominant model, COPD risk was significantly reduced in large studies , in studies enrolling population-based controls , in studies involving Caucasian populations , in studies with doctor-diagnosed COPD , and in ATS-criteria-based COPD . As shown in I2 value of 78.1% in the Asian group and 81.8% in the Caucasian group, indicating that race was not the cause of heterogeneity under the heterozygous genotype model. Under the allele model and the homozygous genotype model, there was no noticeable significance across all subgroups.Given the significant heterogeneity in the overall analyses, explorations were undertaken by subgroup analyses according to ethnicity, sample size, source of controls, matched condition, and diagnosis criteria of COPD, respectively . Under t1, FEV1 predicted ratio, FVC, FVC predicted ratio, and FEV1/FVC in cases and controls under the four genetic models. However, there was no detectable significance for all factors (p > 0.05).Further explorations on the causes of heterogeneity were performed using meta-regression analyses via modeling age, male composition, BMI, percentage of smokers, smoking exposure (cigarette pack-years), FEVThe impact of the first published article on subsequent articles was not significant for the association between rs7041 polymorphism and COPD in cumulative analyses . In addiThe Begg’s funnel plots seemed symmetrical for the association of rs7041 polymorphism with COPD risk under the allele, homozygous genotype, heterozygous genotype, and dominant models . This syp = 0.006) and rs7041-GG genotype carriers  compared to rs7041-TT genotype carriers, with low evidence of heterogeneity , indicating no significant heterogeneity. In other words, race was not a significant cause of heterogeneity in our meta-analysis. The Begg’s funnel plots seemed symmetrical for the association of rs7041 polymorphism with the changes of 25OHD concentrations under homozygous genotype and heterozygous genotype models (Changes in circulating 25OHD concentrations across rs7041 genotypes were assessed. As shown in e models .p = 0.015) was noted after using VDBP gene rs7041 polymorphism as an instrument for Mendelian randomization analyses.Analogous to a randomized controlled trial, Mendelian randomization is developed as a viable strategy to obtain unconfounded and unbiased estimates of causal relevance from observational data. To infer a causal relationship between exposure and disease outcome, two important prerequisites must be met: 1) the selected genes are significantly correlated with intermediate phenotypes or exposure; and 2) the selected genes are significantly correlated with the condition of the disease outcome . To applVDBP gene rs7041 polymorphism with the risk of COPD and circulating 25OHD changes. After integrating the results of 13 articles and 3,389 participants, we observed significant associations of this polymorphism with the risk of COPD and changes in circulating 25OHD concentrations. Importantly, under the rationale of Mendelian randomization, we found a causal relationship between genetically regulated 25OHD concentrations and COPD risk. To the best of our knowledge, this is the first meta-analysis to date that has interrogated the causality between circulating 25OHD and COPD in the literature.In this meta-analysis, we aimed to evaluate the association of VDBP gene rs7041 polymorphism with COPD risk has been widely studied. The association of VDBP gene rs7041 polymorphism is responsible for the binding and transport of vitamin D analogs, as well as certain immune functions (VDBP genetic alterations and circulating 25OHD concentrations. For instance, post hoc test indicated that total 25OHD concentrations were lower in carriers of the rs7041-TT genotype than carriers of the rs7041-GG genotype. In a separate study, Growing evidence shows that vitamin D is a promising biomarker in the development of COPD . The resunctions . In agreVDBP gene rs7041 polymorphism as an instrument for Mendelian randomization analysis, while other VDBP gene polymorphisms were not involved, thus limiting the interpretation of the pooled estimates.Despite the clear strengths of this meta-analysis, including the large sample size and the adoption of the Mendelian randomization technique to infer causality between circulating 25OHD and COPD, several limitations should be acknowledged. First, caution should be taken when interpreting the relationship of circulating 25OHD concentrations with COPD because only two studies, with only 440 COPD patients and 152 controls, were available for analysis. Second, only articles published in the English language were retrieved, which might yield possible selection bias, even though our funnel plots and statistical tests revealed that this bias was unlikely. Third, although several subgroup analyses were conducted to explore potential heterogeneity, including analyses grouped by race, these subgroup analyses could not demonstrate that the target loci are conserved across different ancestries, and we only chose VDBP gene rs7041 polymorphism with the risk of COPD and changes in circulating 25OHD concentrations. Importantly, under the rationale of Mendelian randomization, we found a causal relationship between genetically regulated 25OHD concentrations and COPD risk. Furthermore, our findings have highlighted the importance of employing the Mendelian randomization technique to pinpoint causal biomarkers and have provided clues regarding the causative pathways responsible for the biological regulation of 25OHD concentrations in COPD, thereby shedding new light in the physiology of this disease.In summary, we observed significant associations of