Recently, the serum of C-peptide has been the focus of researchers as a possible predictor of mortality. However, the possible association of serum C-peptide with cardiovascular diseases (CVDs) mortality and all-cause mortality has not been clearly identified. This meta-analysis aimed to assess the relationship between serum C-peptide and the risk of CVDs mortality and all-cause mortality.A comprehensive and systematic search was performed in various important databases, including the PubMed, Web of Science, and Scopus to find relevant studies up to November 2022. The reported hazard ratio (HR) [95% confidence interval (CI)] for all studies was converted into log HR, and their SD was calculated. Then to compute the pooled HR, the random-effects model with inverse variance weighting method was performed.I2 = 76.8%; P-value < 0.001). Also, higher serum C-peptide was related to the increased risk of CVDs mortality .Twenty-three studies were included in the meta-analysis. Fourteen studies reported HR for all-cause mortality, and nine studies for CVDs-related mortality. The pooled results indicate a significant association between serum C-peptide and the risk of all-cause mortality (HR: 1.22; 95% CI: 1.12–1.32, Our investigation suggested that an increased level of serum C-peptide is associated with a higher risk of both CVDs and all-cause mortality. Further, large-scale studies and sufficient samples are recommended to present a convincing link between C-peptide and the risk of CVDs and all-cause mortality.identifier, CRD42022364842. CVDs arInsulin resistance (IR) and hyperinsulinemia (HI) are two hallmarks and risk factors for CVDs events –8, by beDue to the lack of a comprehensive meta-analysis summarizing all available findings in this area, as well as the existence of conflicting results in relevant studies, we conducted the present meta-analysis to summarize the available evidence on the association between serum C-peptide levels with all-cause and CVDs-related mortality. The findings of this meta-analysis will provide important insights into the potential role of serum C-peptide levels as a biomarker for predicting the risk of CVDs mortality and all-cause mortality. This information can be useful for developing risk assessment tools and for identifying the individuals who may benefit from targeted interventions to reduce their risk of CVDs mortality and all-cause mortality.2.2.1.This systematic review and meta-analysis used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses to report the study findings  31). To. To31). 2.2.Initially, we scanned the title and abstract of all studies; then those studies that have examined the association between serum C-peptide levels with all-cause and CVDs-related mortality underwent full-text screening. Studies were included in the current meta-analysis if they were: (1) the original article, (2) cohort design, and (3) reported hazard ratio (HR) with 95% confidence interval (CI). Randomized clinical trials, reviews, meta-analyses, cross-sectional studies, unpublished data, and gray literature including congress abstracts, patents, and dissertations were excluded. PICO  criteria are presented in 2.3.To collect the required information from each study and increase the accuracy, two reviewers conducted the data extraction. The following information was extracted from all included studies: name of the author, the publication date of the study, location, target population, sample size, number of cases, age range and sex of the participants, the method used for C-peptide assessment, outcome, compared categories, HR with 95% CI for C-peptide, adjusted covariates, and the follow-up duration.2.4.NOS) designed for the cohort design by two reviewers, independently . The present meta-analysis includes 15 eligible papers that consist of 23 cohorts. A total of 14 of these cohorts investigated the association between C-peptide levels with the risk of all-cause mortality; however, other studies examined the association with CVDs-related mortality. All included studies reported the measure of association as HR (95% CI). Seven of the 23 studies reported the HR of CVDs and all-cause mortality between the highest and lowest categories of C-peptide level; however, others compared the risk of both outcomes for one unit or one standard deviation (SD) increasing the C-peptide levels. The reported HR (95% CI) for all studies was converted into log HR, and their SD was calculated. Then to compute the pooled HR, the random-effects model with inverse variance weighting method was performed.I2 quantity     and Cochificant)  were use3.3.1.n = 11), irrelevant (n = 3), reported mean ± SD (n = 2), and repetition (n = 1). Finally, 15 papers including 23 studies were included in the meta-analysis. Fourteen studies reported HR for all-cause mortality and nine studies for CVDs-related mortality.As presented in 3.2.n = 12), Italy (n = 5), Germany (n = 2), Sweden (n = 2), New Zealand (n = 1), and China (n = 1). The number of participants in the studies investigated the association between serum C-peptide, with the all-cause and CVDs-related mortality ranging from 84 to 5,902 and with an age range of 18–91 years. During the follow-up period that ranged from 1.46 to 17 years, a total of 9,530 deaths occurred .The characteristics of the 23 included studies are reported in n = 2) and both genders (n = 21). As previously mentioned, all cohort studies reported the measure of association as HR and 95% CI.The studies included females (n = 20), sex (n = 18), underlying disease (n = 17), smoking (n = 15), BMI (n = 15), blood pressure (n = 10), glomerular filtration rate (n = 9), triglycerides (n = 7), and alcohol consumption (n = 5). All studies had high quality based on the NOS criteria .n = 8, Europe: n = 4, Oceania: n = 1, and Asia: n = 1), diabetes status , cancer status (cancer: n = 5 vs. non-cancer patients: n = 9), and type of exposure analysis  to find the source of heterogeneity in the studies that assessed the association between serum C-peptide and the risk of all-cause mortality .n = 4, and Europe: n = 5), diabetes status , and type of exposure analysis  to find the source of heterogeneity of studies that assessed the association between serum C-peptide and risk of CVDs-related mortality. According to the results given in A subgroup analysis was performed based on the region (studies conducted in the United States: 3.3.3.P = 0.014). This finding suggests that for each participant increase in the sample size, the pooled HR increases by 1.00008-fold. Even by adjusting the age, year, cancer status, and region, the significant reduction effect of the sample size on the τ2 remained. Although after adding more than one covariate to the adjusted model, the sample size effect was attenuated and become non-significant, it may be influenced by the low number of included studies as it needed to add some covariates for adjustment.We fit a meta-regression model including the age of participants and other covariates of interest. The model showed that a great percentage of this heterogeneity can be explained by the sample size of the study . Likewis3.3.4.P = 0.04). This finding suggests that for each unit increase in the year of publication, the pooled HR increases by 1.10-fold. However, adjusting the possible confounding variables lead to a disappearance of the significant association observed for the year of publication. In all adjusted models for different variables, the τ2 was significantly decreased.We fit a meta-regression model including the age of participants and other covariates of interest. The model showed that a great percentage of this heterogeneity can be explained by the year of publication  Supplem. In this3.4.P-value = 0.460) , the trim-and-fill method was performed to calibrate publication bias. Two missing studies were identified by the trim-and-fill method for all-cause mortality. However, a minimal difference (0.04) was observed between the pooled estimate and random-effects model trimming estimation HR and 95% CI of model trimming estimation, which was 1.18 (1.08–1.29). Since this minimal difference does not affect the observed relationship, therefore, this amount of publication bias does not cause a problem.A visual inspection of the funnel plot, Begg's test, and Egger's test indicated a publication bias in the association between serum C-peptide and the all-cause mortality ; however= 0.460) . This sh3.5.According to the sensitivity analysis using a random-effects model, excluding none of the studies had a considerable change on the pooled effect size of the association between serum C-peptide and the all-cause mortality (range: 1.17–1.27) , and bet4.4.1.To the best of our knowledge, the present study is the first meta-analysis that compiled and reviewed the available literature from relevant observational studies that have assessed whether higher serum C-peptide level is associated with an increased risk of both CVDs and all-cause mortality. The present meta-analysis showed that higher serum C-peptide level was associated with an increased risk of all-cause mortality and CVDs mortality by 22% and 38%, respectively. Out of the 14 studies that have investigated all-cause mortality, eight studies have reported a positive relationship between serum C-peptide levels and all-cause mortality –23. Out 4.2.Accumulating evidence from observational studies suggested that higher C-peptide serum level might increase all-cause mortality rates by increasing the risk of important chronic diseases, such as several types of cancer –38, CVDsIn the current study, the heterogeneity for all-cause mortality was 76% and for CVD mortality was 80%, and these results are significant. To further identify the source of heterogeneity, we performed subgroup analysis and meta-regression analysis. Based on the meta-regression analysis, the sample size in all-cause mortality and publication year in CVD mortality can be a positive source of heterogeneity. It is probable that in higher sample volumes and also with the updating of the measurement tool, the measurement of C-peptide level has been performed better, which helps people to be better classified, that is, people with different C-peptide levels can be better distinguished from each other, which makes the risk better detectable.In the subgroup analysis for all-cause, we divided the studies into three subgroups, according to the location of residence, diabetes status, and cancer status. In CVD mortality, the studies were divided into two subgroups, according to the place of residence and diabetes status. Accordingly, in all-cause mortality, the location of residence is a source of heterogeneity, which is the reason for a large number of studies conducted in the United States and Europe compared with Asia and the Pacific. In CVDs mortality, the diabetes status is a source of heterogeneity. The reason for this could be that it is difficult to differentiate between people with different levels of C-peptide since the basic levels of C-peptide are high in all diabetics. However, in non-diabetic people, the difference between serum C-peptide levels is much clearer than that in diabetic people, and it is easier and better to separate people based on this. In such people, high levels of serum C-peptide indicate the presence of a metabolic disorder that can significantly increase the risk of mortality.4.3.Several mechanisms have been proposed to explain the relationship between higher serum C-peptide levels and increased mortality. Insulin and C-peptide are secreted in equal proportion from pancreatic beta cells. C-peptide is a biomarker of insulin synthesis and was used as a surrogate biomarker of insulin in epidemiologic studies because it has a longer half-life than insulin and so is more stable . The cur4.4.The present meta-analysis had some strengths. First, we have entered the number of significant studies that provided a relatively high sample size. Also, the countries where these studies were conducted were of good diversity. The assembly of these factors allowed us to obtain valid results from the composition of the data and to effectively discover the sources of heterogeneity between studies. Second, in CVD mortality, publication bias was not observed, but it was significant in all-cause mortality. In this context, two studies that were sources of bias were discovered, and after adjusting their effect, there was no significant change in the thousand ratios (4%). There are also some limitations in our meta-analysis. Some of the included studies have relatively small sample sizes. An unmeasured and residual confounding may lead to the inability to draw definitive conclusions. The included studies were adjusted for different covariates, and this meta-analysis pooled the adjusted HR that were adjusted for different variables. The analysis was also limited in terms of the quality of the single studies, and many other factors affecting CVD and all-cause mortality incidence could not be covered properly. Also, the included studies in our meta-analysis reported C-peptide as the quantitative and categorical variable that seems the combined obtained result is challengeable. For this reason, we conducted a subgroup analysis based on the type of exposure analysis (per 1 unit and highest vs. lowest category).In conclusion, our study revealed that an increased level of serum C-peptide is positively associated with the risk of both CVD and all-cause mortality. Regarding the mentioned limitations, further large-scale studies and sufficient samples are needed to present a convincing link between C-peptide and the risk of CVD and all-cause mortality.


MTHFR) gene C677T polymorphism with the incidence of gestational diabetes mellitus (GDM) in the Chinese population remains controversial. This study aimed to further clarify the effect of the MTHFR gene C677T polymorphism on GDM risk among Chinese pregnant women based on current evidence.The relationship of the methylenetetrahydrofolate reductase  was performed by TSA version 0.9 beta software to determine the required information size.Several databases were searched up to July 29, 2023 for relevant case-control studies. The numbers of patients with and without the T allele of the MTHFR gene C677T polymorphism was significantly associated with an increased risk of GDM, which was manifested by the five gene models of the MTHFR C677T polymorphism . Subgroup analysis based on the regions indicated that the significant relationship between the T allele of the MTHFR gene C677T polymorphism and an increased risk of GDM was detected only among the southern population . TSA plots showed that the information sizes for the association between the MTHFR gene C677T polymorphism and GDM risk were sufficient in the homozygote (TT vs. CC) and recessive (TT vs. TC+CC) models.A total of 17 case-control studies involving 12345 Chinese participants were included. The pooled results demonstrated that the T allele of the MTHFR gene C677T polymorphism is closely related to susceptibility to GDM in the southern Chinese population, and the C-T mutation serves as an important genetic risk factor for GDM. More well-designed large case-control studies are needed to further confirm the above findings.The  Gestational diabetes mellitus (GDM) is a common complication during pregnancy, posing significant health risks to both the fetus and the mother. The incidence of GDM has been rising, with reported rates ranging from 1% to 14% internationally and from 2% to 18% in China . FurtherHomocysteine (Hcy) is a reactive amino acid associated with vascular injury that impacts glucose and lipid metabolism. Previous studies have indicated that Hcy levels are higher in GDM patients than in women with normal pregnancies, suggesting a potential close relationship between Hcy levels and GDM and its complications . RelevanMTHFR) can catalyze 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, participating in the remethylation of Hcy and keeping Hcy levels relatively low in the body. Variations in the MTHFR gene can lead to disruptions in multiple physiological and biochemical reactions in the body, such as modifications in the methylation of nucleic acids and proteins and the regulation of the cell cycle. The MTHFR gene is located on the short arm of human chromosome 1 (1p36.3), and polymorphisms in the MTHFR gene can result in reduced enzyme activity, causing folate metabolism disturbances, reduced 5-methyltetrahydrofolate production, impaired DNA methylation, metabolic disruptions of Hcy, and the accumulation of Hcy in the bloodstream. Currently, hundreds of single nucleotide polymorphisms (SNPs) have been identified in the MTHFR gene, with the C677T site being the most closely associated with diseases. When this gene polymorphism occurs, it may lead to reduced or impaired MTHFR enzyme activity, disrupted folate metabolism, and elevated Hcy levels and consequently result in related complications (MTHFR gene C677T polymorphism is closely related to the risk of diabetes mellitus (DM)  , 15. Somy to GDM , 17. HowMTHFR gene C677T polymorphism on GDM risk among Chinese pregnant women based on current evidence.Therefore, this meta-analysis aimed to further identify the effect of the The current meta-analysis was performed according to the Preferred Reporting Items for Systematic Review and Meta-Analyses 2020 guidelines .MTHFR. The detailed search strategy was as follows: (single nucleotide polymorphism OR SNP OR polymorphism) AND  AND (methylenetetrahydrofolate reductase OR MTHFR). Moreover, MeSH terms and free-text words were both applied, and references cited in the included studies were also reviewed.In this meta-analysis, the CNKI, VIP, WanFang, Medline, Web of Science and EMBASE databases were searched from inception to July 29, 2023. The following terms were used during the search: single nucleotide polymorphism, SNP, polymorphism, gestational diabetes mellitus, pregnancy-induced diabetes, methylenetetrahydrofolate reductase and MTHFR gene C677T polymorphism and the incidence of GDM among pregnant Chinese women; 2) studies in which the numbers of patients with and without the T allele of the MTHFR gene C677T polymorphism in the GDM and control groups were provided for the calculation of odds ratios (ORs) with 95% confidence intervals (CIs); and 3) high-quality studies with a Newcastle-Ottawa Scale (NOS) score of 6 or higher (Studies that met the following criteria were included: 1) studies of the association between the r higher .Studies that met the following criteria were excluded: 1) letters, editorials, animal trials, reviews or case reports; and 2) studies with duplicated or overlapped data.The following information was extracted from each included study: the first author, publication year, sample size, number of patients with and without GDM, genotype detection method, number of patients with different genotypes and NOS score.The NOS was applied to assess the methodological quality of the included studies because all included studies were cohort studies. As mentioned above, only studies with an NOS score ≥ 6 were included.The literature search, literature selection, data extraction and quality assessment were independently conducted by two authors, and all disagreements were resolved by team discussion.2 statistics and the Q test. If significant heterogeneity was detected, defined as I2 > 50% and/or P < 0.1, the random effects model was applied; otherwise, the fixed effects model was applied  was conducted according to the guidelines of former publications , 25. A sThe specific literature search and selection process is shown in As shown in MTHFR gene C677T polymorphism was significantly related to the risk of GDM in the allele model      (The pooled results demonstrated that the P<0.001) Figure 2MTHFR gene C677T polymorphism and an increased risk of GDM only among the southern population in the allele model , homozygote model , heterozygote model , dominant model  and recessive model . Although a significant difference in the allele model and heterozygote model was not shown, an obvious tendency was observed  are needed to further confirm our findings.The current meta-analysis included 17 relevant studies with 12345 participants and explored the relationship between the It has been reported that the serum Hcy level in GDM patients is significantly higher than that in non-GDM patients . Serum HMTHFR gene is an important factor leading to elevated Hcy levels (MTHFR is a key enzyme involved in Hcy metabolism, catalyzing the conversion of 5,10-methylenetetrahydrofolate to 5-methyltetrahydrofolate, which promotes the conversion of Hcy to methionine (MTHFR isoleucine, resulting in decreased MTHFR enzyme activity. This impedes the conversion of Hcy to methionine, leading to the accumulation of Hcy in the body and subsequently causing an increase in the serum Hcy concentration, which contributes to the development of GDM (MTHFR CT heterozygous mutations reduced enzyme activity to approximately 75% of the CC type, while TT genotype mutations led to even more significant decreases, reaching approximately 50% or lower (MTHFR C677T can cause a reduction in MTHFR enzyme activity, resulting in elevated serum Hcy levels. Therefore, the T variant allele in the MTHFR gene C677T polymorphism leads to an increased risk of GDM.The reduction in enzyme activity caused by the C677T mutation in the y levels . MTHFR ithionine . The C67t of GDM . The resor lower . The afoMTHFR gene C677T polymorphism and an increased risk of GDM. However, studies by Fang et al. (MTHFR C677T and plasma Hcy levels, suggesting that the T variant allele in the MTHFR gene C677T polymorphism may have a relatively minor impact on Hcy metabolism in pregnant Han Chinese women. However, this mutation may reduce the risk of GDM through the alteration of other metabolic pathways within the body, thereby masking the potential adverse effects of Hcy metabolism changes caused by the C-T mutation in MTHFR C677T (Most included studies revealed a relationship between the g et al.  and Yangg et al.  reportedFR C677T . In addiFR C677T . MoreoveThere are several limitations in our meta-analysis. First, the sample sizes in several included studies were relatively small, which might cause some bias. Second, the genotyping methods in the included studies differed, and the accuracy of different methods may vary. Third, a more detailed subgroup analysis based on other important parameters, such as race and age, could not be performed because the original data were unavailable. Fourth, significant heterogeneity among the included studies was detected.MTHFR gene C677T polymorphism is closely related to susceptibility to GDM in the southern Chinese population, and the C-T mutation serves as an important genetic risk factor for GDM.The The original contributions presented in the study are included in the article/XT: Conceptualization, Data curation, Formal Analysis, Methodology, Writing – original draft. HC: Project administration, Supervision, Validation, Writing – review & editing.


FTO, is associated with both GDM and Type 2 diabetes mellitus(T2DM). We conducted a meta-analysis on the association between the FTO single nucleotide polymorphism (SNP) rs8050136 and T2DM, followed by a case-control study on the association of the said SNP and GDM in a sample of Bangladeshi women.Gestational diabetes mellitus (GDM) is a growing public health concern that has not been extensively studied. Numerous studies have indicated that a variant (rs8050136) of the fat mass-associated gene, FTO rs8050136 and GDM. Genotyping was performed using the tetra-primer amplification refractory mutation system-polymerase chain reaction (T-ARMS) method, and statistical analyses were performed using various statistical softwares.A total of 25 studies were selected after exploring various databases and search engines, which were assessed using the Newcastle-Ottawa Scale (NOS). The MetaGenyo web tool was used to conduct this meta-analysis. A case-control study was performed on 218 GDM patients and 284 controls to observe any association between FTO rs8050136 polymorphism and an elevated risk of T2DM under all genetic models (P<0.05). In the case-control study, synergistic analyses of the SNP and gravida with GDM revealed a significant (P<0.01) association with an increase in odds by 1.6 to 2.4 folds in multigravida and decrease in odds by 2 folds in primigravida. A positive family history of diabetes and the minor allele of this SNP collectively increased the risk of developing GDM by many-fold (1.8 to 2.7 folds). However, after accounting for family history of diabetes and gravidity, analyses showed no significant association with GDM.In the meta-analysis 26231 cases and 43839 controls were examined. Pooled association analyses revealed a statistically significant relationship between the FTO with T2DM, and this variant was substantially associated with an increased risk of GDM in a sample of Bangladeshi multigravida women.Our meta-analysis revealed a significant association between SNP rs8050136 of  Gestational diabetes mellitus (GDM) is a metabolic disorder that affects glucose tolerance during pregnancy, and may resolve after delivery . It is aKCNJ11) . Commercial kits were used to assay plasma glucose by the glucose oxidase method in an automated analyzer . If the glycemic status was found to be normal when tested before the 24th week of gestation, the mother was advised to repeat the OGTT during the 24th to 28th week of gestation, and the glycemic status was reconsidered.® K2 EDTA (BD Franklin Lakes NJ USA) tubes. Genomic DNA was extracted from this blood sample using the PureLink® Genomic DNA extraction kit (Invitrogen) according to the manufacturer’s instructions. The concentration and purity of the extracted DNAs were tested with NanoDrop 2000 UV Vis Spectrophotometer. DNA samples with an OD260/OD280 ratio between 1.8–1.85 and concentrations more than 80 ng/mL were used for genotyping.Peripheral blood samples of patients and controls were collected in BD VacutainerFTO gene. The primers were designed using the Primer1 program [5′-CTTAAGAGTCCATACCAACCAAGGT-3′; outer Reverse 5′ATAATTGGCTCTCGACATT TACACA-3′; inner Forward 5′-AGTTGCCCACTGTGGCAGTC-3′ and inner Reverse 5′-GCAAAAACCACAGGCTCAGATACTT-3′. To increase the specificity of the reaction, the inner primers were designed to have a mismatch at the −2 position from the 3′ terminal. The PCR cycles consisted of an initial denaturation step of 5 min at 95°C, followed by 30 cycles of 50s at 95°C, 45 s at 62°C, and 45s at 72°C. The final extension was for 7 min at 72°C. Two nonallele specific outer primers amplify 337 bp region that comprises the SNP, while two allele specific inner primers paired with each of the outer primers, and produce the allele specific fragments 251 bp and 130 bp. Subsequently, 7μl of the amplified product was subjected to 2% agarose gel electrophoresis and stained with ethidium bromide. The appearance of two bands of 337 bp and 251 bp indicated the presence of AA genotype, whereas 337 bp and 130 bp products indicated the CC genotype. When the heterozygous genotype AC is present, three bands are visible: 337 bp, 251 bp, and 130 bp [The T-ARMS-PCR method  was empl program . The tard 130 bp .FTO locus. Chain terminating cycle sequencing for both outer forward and outer reverse primer was performed using a sequencing kit . Capillary electrophoresis was performed using the ABI 3500 Genetic Analyzer . Sequences were analyzed to determine the genotype using sequencing analysis software, version 5.2 . T-ARMS-PCR genotyping results were validated by sequencing blindly selected samples [Sanger’s di-deoxy chain-terminating method was used to sequence the amplified  samples . No diff2) test with a P>0.05 criterion. Multivariate logistic regression was used to identify GDM risk variables. The general relationship of genotypes with GDM was examined with multivariate logistic regression analysis under codominant, dominant, recessive, overdominant, and log-additive models and adjusted for family history of diabetes and gravidity using SNPStats [The normality of the random variables was tested visually by inspecting histograms in R statistical software version 4.0.3 for case control data analysis. Student’s t-tests were used to compare the ages, BMI, systolic blood pressure, diastolic blood pressure, and plasma glucose levels  between the GDM and control groups, while the chi-square test was used to examine the family history of diabetes and gravidity between these groups. Numerical variables were expressed as mean ± standard deviation of the mean (mean ± SD). Categorical variables, on the other hand, were given as numbers (n) and percentages (%). Hardy-Weinberg equilibrium (HWE) was assessed in cases and controls separately using Pearson’s chi-squared  under all genetic models  higher age (27.57±4.60 vs. 25.46±4.78), BMI (26.64±4.03 vs. 25.19±3.84), diastolic blood pressure (DBP: 70.65±9.16 vs. 68.83±8.99), plasma glucose levels ; a higher percentage of positive family history of diabetes , multigravida  and lower percentage of primigravida  compared to the control group. However, there was no significant difference between the two groups in terms of systolic blood pressure , positive bad obstetric history  and occupation . SBP, BOH, and occupation were indecipherable between control and GDM groups whereas significant differences were observed in age, BMI, DBP, FH, and gravidity. Age , BMI  and DBP  had odds very close to 1, indicating that they were not strong risk factors for GDM. On the other hand, positive family history of diabetes  and multigravidity  were significantly associated with increased risk of GDM. These variables were adjusted for in subsequent analyses after checking their impact on GDM by multivariate logistic regression.This study enrolled 502 pregnant women classified into 218 with GDM and 284 normoglycemic control subjects. The age of the participants ranged from 18 to 44 (years). The GDM group had significantly(P<0.05) higher age BMI, plasma glucose levels and DBP compared to women of primigravida. There was no significant difference in the positive family history of diabetes between the primigravida and the multigravida group. The percentage of GDM was significantly higher in the multigravida group than in the primigravida group , whereas the percentage of normoglycemic women was higher in the primigravida group than in the multigravida group . In both groups, participants with GDM had significantly higher age, BMI, plasma glucose levels, and positive family history of diabetes than control participants  models after adjusting for family history of diabetes and gravidity. In the rest of the models, the odds remained between 1.1 and 1.2, with P values greater than 0.05  under codominant and dominant models  and overdominant  models in primigravida group. A similar protective role was also observed under the dominant model  in the same group and was statistically significant (P = 0.0021). In contrast, the CC genotype of reference allele showed significant protection against GDM in multigravida under codominant , dominant , and overdominant  models (P = 0.0068) by 1.8 folds (OR = 1.51) in the presence of AC and 2.3 folds (OR = 1.96) in the presence of AA genotypes. The AC genotype significantly increased the odds of GDM in multigravida women by 2.8 and 2.9 folds under codominant and overdominant models, respectively, compared to primigravida women. On the other hand, the AA genotype increased the odds by 1.8 folds under codominant and recessive models  models . The pree models . AnalysiP = 0.022) showed a statistically significant reduction both before and after adjustment , recessive  and over dominant  models (To detect the cumulative effect of ) models . Convers) models . None ofFTO SNP rs8050136 on susceptibility to T2DM. The meta-analysis of the selected dataset confirmed that the minor A allele of this FTO variant may increase the risk of developing T2DM in five genetic models.Meta-analyses are conducted to evaluate the reliability of the available evidence, for example, the nature of association in case-control studies , 83. The2-test-based Q test and I2 were conducted to assess the heterogeneity of the studies [2 > 50.0% indicates prominent heterogeneity between the studies, thus making the random effect model [FTO rs8050136 polymorphism and T2DM risk occurred only among Asians and not among non-Asians, which is consistent with the results of previous meta-analyses [The mean of the distribution of true effects was estimated using the random-effects model. Even though the number of cases present in the studies ranged from 51 to 3035 and the number of controls subject varied from 56 to 9873, studies with larger sample sizes provide better estimates than smaller ones. Each study measured a distinct effect size, and each of these effect sizes served as a sample from the population whose mean we have attempted to estimate. As a result, the weights assigned under random effects were more balanced compared to the fixed effects model. Small studies are less likely to be ignored, whereas extensive studies are less inclined to dominate the analysis . Cochran studies , for whict model  more suict model  is more analyses , 86. Altanalyses . Studiesanalyses , which aThe number of association studies between the SNP rs8050136 and GDM is insubstantial. Moreover, a recent meta-analysis reported by H. He et al., 2018 was limited to only Caucasians due to the unavailability of data from other ethnicities, thus the conclusion could not be applied to all populations . TherefoFTO SNP rs8050136, in particular, is not a prominent genetic regulator in the etiology of GDM in the ethnic groups analyzed, but it is located in an area of considerable linkage disequilibrium of the gene’s intron 1 [FTO SNPs and the risk of GDM, other studies have found the opposite; therefore, no clear conclusion has been established [P = 0.30) and Saucedo, Renata et al.  we found no significant association (P = 0.18) between the FTO rs8050136 with GDM but odds (OR = 1.63) of this disease is 1.5 folds higher in the population under study [The consistency of the genotype distribution of the target SNP with HWE in the case and control groups indicated that there was no selection bias, population stratification, or genotyping error in the study population . Severalintron 1 . Althougablished , 92. In er study , 55. NotP-values in the different models can be attributed to the small sample size of the subgroups  and family history of diabetes (OR  =  1.84) as confounders for higher risk of GDM. This is consistent with previous studies that have identified family history of diabetes and multigravida as risk factors for GDM –95. To cubgroups  Tables.FTO rs8050136 variant are more susceptible to developing GDM than primigravida women, although FTO rs8050136 did not show any statistically significant association with GDM (P < 0.05), which was similar to our findings in the presence of heterozygous risk allele of the target SNP  between the incidence of GDM in multigravida (47%) and primigravida (38%) groups. Studies conducted in India and Pakistan also showed a lower incidence of GDM in primigravida [Multigravida is not only an important predictor of GDM but also affects the prevalence of the disease , 103. Inigravida , 105.However, the meta-analysis of this study has some limitations that should be considered. Drawbacks, such as insufficient sample sizes of some of the studies, selection bias in the recruitment of patients and controls, and the lack of confounder adjustment, might lead to uncertain outcomes. The number of comparable studies that adjusted for the family history of diabetes was insufficient to perform a meta-analysis. On the other hand, the outcomes of case-control analysis might be specific to pregnant women who were recruited from urban areas such as Dhaka, Narayanganj, and Gazipur that may not be representative of the entire population. This could also explain the nature of the association found in this study between the target SNP, gravidity, and, GDM. Even though several risk factors are addressed in this study, other GDM-related factors such as food intake and physical activity could not be considered, due to a lack of information. As a consequence, the interactions between lifestyle factors and this variant in terms of GDM remain unexplored. As the SNP rs8050136 is an intron variant, the molecular mechanism of how they modulate GDM risk remains largely unknown.FTO gene variant rs8050136 and T2DM risk, especially in Asian populations. In multigravida women, FTO rs8050136 significantly increased the risk of GDM, while no evidence of a direct association was found between this variant and GDM risk in our population.Overall, the existing evidence indicates a positive association between the FTO rs8050136 significantly increases the risk of type 2 diabetes in the Asian population under all genetic models. This association was primarily observed in the East-Asian population but not in the South Asian, which might be attributed to its smaller sample size. Additionally, we investigated the association between FTO rs8050136 and the risk of GDM in the Bangladeshi population. This revealed that in the presence of multigravidity, the SNP significantly increased the risk of GDM under codominant, dominant, and overdominant models. Therefore, more epidemiological studies are required to confirm this association to establish FTO rs8050136 as a biomarker of GDM forewarning in multigravida women. The elucidation of biological underpinnings underlying the association is of utmost importance.The current meta-analysis revealed that S1 Table(DOCX)Click here for additional data file.S2 Table(DOCX)Click here for additional data file.S3 Table(DOCX)Click here for additional data file.S4 Table(DOCX)Click here for additional data file.S5 Table(DOCX)Click here for additional data file.S6 Table(DOCX)Click here for additional data file.S7 Table(DOCX)Click here for additional data file.S8 Tablea adjusted for gravidity and family history of diabetes.(DOCX)Click here for additional data file.S9 Tablea adjusted for gravidity.(DOCX)Click here for additional data file.S10 Tablea adjusted for family history of diabetes.(DOCX)Click here for additional data file.S11 Tablea adjusted for family history of diabetes.(DOCX)Click here for additional data file.S12 Tablea adjusted for family history of diabetes.(DOCX)Click here for additional data file.S13 Table(DOCX)Click here for additional data file.S14 Table(DOCX)Click here for additional data file.S15 Table(DOCX)Click here for additional data file.S1 File(DOCX)Click here for additional data file.S2 File(DOCX)Click here for additional data file.S1 Fig(PNG)Click here for additional data file.


Osteosarcopenia is a syndrome with a concomitant presence of both sarcopenia and osteopenia/osteoporosis. It increases the risk of frailty, falls, fractures, hospitalization, and death. Not only does it burden the lives of older adults, but it also increases the economic burden on health systems around the world. This study aimed to review the prevalence and risk factors of osteosarcopenia to generate important references for clinical work in this area.Egger’s test, Begg’s test, and funnel plots were used to test the publication bias. Sensitivity analysis and subgroup analysis were conducted to identify the sources of heterogeneity. Statistical analysis was performed using Stata 14.0 and Review Manager 5.4.Pubmed, Embase, Cochrane Library, Web of Science, CNKI, Wanfang, CBM, and VIP databases were searched from inception until April 24th, 2022. The quality of studies included in the review was evaluated using the NOS and AHRQ Scale. Pooled effects of the prevalence and associated factors were calculated using random or fixed effects models. CI: 0.16–0.26). The risk factors for osteosarcopenia were female , older age , and fracture .A total of 31 studies involving 15,062 patients were included in this meta-analysis. The prevalence of osteosarcopenia ranged from 1.5 to 65.7%, with an overall prevalence of 21% (95% The prevalence of osteosarcopenia was high. Females, advanced age, and history of fracture were independently associated with osteosarcopenia. It is necessary to adopt integrated multidisciplinary management.The online version contains supplementary material available at 10.1186/s12877-023-04085-9. The concept of osteosarcopenia (OS) was first proposed by Duque and colleagues  as the pIn recent years, increasing evidence suggests a close connection between muscles and bones. Apart from mechanical interactions, they are also affected by endocrine factors and have extensive genetic and molecular associations . The “meIn the past few years, the increased interest in the field of osteosarcopenia among clinicians and researchers has led to the publication of numerous studies on the prevalence and risk factors of osteosarcopenia. To date, there are two systematic reviews on the epidemiology of osteosarcopenia. Yoo et al. summarized the epidemiology of osteosarcopenia in Korea . NielsenThis systematic review and meta-analysis were performed according to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines . It was Eight databases including Pubmed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang, China Biomedical Literature Database (CBM), and VIP database were searched to obtain relevant literature. The references in the literature were also screened for relevant studies. The retrieval time ranged from the establishment of the database to April 24th, 2022. The English search terms were based on a combination of relevant MeSH terms, i.e. “osteoporosis”, “sarcopenia”, “risk factors”, and “prevalence”. It was also supplemented by the method of literature traceability to ensure that as much literature was searched as possible.OR, 95% CI) were provided or could be generated from the raw data in the study.The inclusion criteria for the review included: (1) Observational study designs such as case-control, cross-sectional, and longitudinal cohort studies; (2) The study population was the general adult population; (3) Prevalence with or without risk factors of osteosarcopenia was reported in the study; (4) Clear and valid diagnosis of osteopenia/osteoporosis and sarcopenia; (5) Relevant data on the prevalence of osteosarcopenia, as well as relevant risk factors in the form of odds ratio (The exclusion criteria included: (1) Reviews, article reviews, lectures, case reports, conference abstracts, and animal experiments; (2) Poor data quality, small sample data, repeated publications, or similar studies; (3) Data with obvious errors, incomplete data that cannot be utilized, poor quality literature, and inability to obtain the data needed for the study.Two authors independently screened the titles and abstracts of all articles. The screening results of the two reviewers were compared. Any differences were discussed to obtain a consensus. Full-text reviews and data extraction were then independently performed by the same two reviewers. The results were again compared and discussed for agreement. If there are any unresolved discrepancies between the two reviewers at any stage, a third reviewer was consulted.The following data were extracted using Excel spreadsheets by two reviewers independently, i.e. authors, year of publication, title, study design, region, sample size , diagnostic criteria of osteoporosis and sarcopenia, the prevalence of osteosarcopenia, as well as associated risk factors.≥ 7 is classified as high-quality literature.For the quality assessment of a cross-sectional study, the 11-item criteria recommended by the US Agency for Healthcare Quality and Research (AHRQ) was used. A score of 0 to 3 indicates low quality, 4 to 7 indicates medium quality, and 8 to 11 indicates high quality. For cohort studies, the Newcastle-Ottawa Scale (NOS)  was usedCI were determined. The heterogeneity was tested using I2. The data were considered significantly heterogeneous if I2 > 50% and the random effects model would be used. Otherwise, the fixed-effects model was used. Sensitivity analysis and subgroup analysis were used to explore the sources of heterogeneity. The risk of publication bias was assessed by Egger’s and Begg’s tests as well as funnel plots. All the statistical analysis was conducted using STATA 14.0 . However, the ORs and 95% CIs for pooled risk factors were calculated using Review Manager 5.4. A p-value of < 0.05 was considered statistically significant.In this meta-analysis, the combined prevalence of osteosarcopenia and 95% From the total of 2329 relevant articles retrieved, 1844 articles remained after removing duplicate literature. Following that, another 1790 studies were excluded after reviewing the titles and abstracts. The remaining 54 literatures were evaluated by reviewing the full text. Finally, only 31 studies with a total of 15,062 patients , 33–61 wn = 13)   using a random effects model.The results showed that the prevalence of osteosarcopenia ranged from 1.5 to 65.7%, with an overall prevalence of 21% [95% CI 12–36%; I2 = 96.92, p = 0.00) while the prevalence of 26 studies from 2018 to 2022 was 20% . In terms of gender, the prevalence of osteosarcopenia among females was higher at 28%  than males at 14% . When analyzed by region, the prevalence was 18%  in 13 studies from Asia while the eight European studies showed a prevalence of 26% . The prevalence in the six Oceania studies was 21%  while the three South American studies showed a prevalence of 23% (95% CI: 5–48%) as compared to the study from North America with a prevalence of 11% (95% CI: 8–15%)  and 33%  respectively. The prevalence was much lower in the community-dwelling group with 12% . Based on the different diagnostic criteria of sarcopenia, the prevalence was 15% under the EWGSOP2 criteria  as compared to 30%  when using the EWGSOP criteria. When using AWGS2 and JSH criteria, the prevalence of osteosarcopenia was 17%  and 18% (95% CI: 15–21%), respectively. When using AWGS criteria, the prevalence was 20% (95% CI: 11–30%). When using the FNIH criteria, the prevalence was higher at 46% (95% CI: 42–50%). The prevalence of osteosarcopenia under other criteria was the lowest at 9% (95% CI: 7–12%). When using sarcopenia plus osteoporosis to define osteosarcopenia, its prevalence is 17% (95% CI: 10–26%), but when using another definition, the prevalence increases to 24% (95% CI: 17–32%). . From the results, it could be considered that there was no publication bias , older age , and fracture  were risk factors of osteosarcopenia. However, high parathyroid hormone (PTH)  and high body mass index (BMI)  were not significantly associated with osteosarcopenia. Meta-analysis could not be performed for other factors due to insufficient data  compared to men , 47. The.6% compaThere are several advantages to the current study. Firstly, it is a large global sample that quantitatively combines the prevalence and risk factors of osteosarcopenia. Secondly, through subgroup analysis , heterogeneous factors that lead to the estimated prevalence of osteosarcopenia reduction are explored. Finally, this study proposes strategies for preventing and managing osteosarcopenia, such as dietary regulation, exercise intervention, medication therapy, physical assessment, etc., providing clinical doctors with effective guidance and suggestions. Overall, this study has practicality and operability, and provides important references for the health management of the elderly.≥ 85 years old [≥ 80 years old [This study also has some shortcomings. Firstly, This systematic review does not include any articles not written in English. Next, the heterogeneity of the combined data in the selected studies was high. Even after subgroup analysis, the heterogeneity between studies was still high. If sufficient data are available, severe sarcopenia can be evaluated separately in the diagnosis. Additionally, some studies measured only muscle mass and strength without any assessment of step speed. Thus, this could have influenced the overall results. In addition, we could not summarize the prevalence by age groups as different age groups were used by the studies. For instance, one study reported the prevalence of osteosarcopenia for the age groups of 65–74, 75–84, and ears old while patears old . Most ofIn summary, the meta-analysis found that the prevalence of osteosarcopenia was high. Moreover, females, advanced age, and a history of fracture were independently associated with osteosarcopenia. Therefore, early assessment and timely intervention should be undertaken among high-risk populations to prevent or delay the disease progression.Below is the link to the electronic supplementary material.Supplementary Material 1Supplementary Material 2Supplementary Material 3Supplementary Material 4Supplementary Material 5Supplementary Material 6Supplementary Material 7Supplementary Material 8Supplementary Material 9


For evaluation of the correlation between tea drinking and the risk of carcinoma of the urinary bladder.  By searching PubMed, Embase, and Cochrane Library databases, the original studies on tea drinking and carcinoma of the urinary bladder risk were collected, the data were extracted, and meta-analysis package 5.2-0 of R language was used for meta-analysis.  This study contained 11 researches, composed of 7686 patients and 10320 controls. Tea drinking was not linked to carcinoma of the urinary bladder risk .  Tea drinking may not be linked to carcinoma of the urinary bladder, but more definitive results are needed from higher-quality trials. Carcinoma of the urinary bladder is the most frequently diagnosed tumor in the urinary system, ranking 11th in the incidence of malignant tumors. The annual number of carcinoma of the urinary bladder deaths is about 170,000 . BladderAlthough the exact risk elements for carcinoma of the urinary bladder have not been elucidated, studies have found that there are risk elements linked to carcinoma of the urinary bladder. Various geographical factors, genes, and personal habits are Risk elements for carcinoma of the urinary bladder, such as smoking, age, etc. –5. VegetInclusion criteria is as follows: (1) Human subjects; (2) the article type was case-control study; and (3) the language is English. Exclusion criteria is as follows: (1) Review, abstracts, and conference papers; (2) unable to obtain the full text; (3) low-quality literature (NOS ≤ 5 points); (4) human in vitro test, (5) concomitant with other cancers; and (6) metastatic bladder cancer.“Carcinoma of the urinary bladder,” “bladder carcinoma,” “bladder neoplasm,” and “tea” were used as keywords to search the databases  for articles published before May 2022 that met the inclusion exclusion criteria.Two investigators independently conducted literature search and performed literature screening based on inclusion and exclusion criteria, with confirmation by the principal investigator in case of disagreement. Data extraction was performed separately for the included literature by developing data collection forms including authors, follow-up time, sample size, and RR or OR including 95% CI for carcinoma of the urinary bladder as well as nontumor control group. If the article examined the effect of different tea drinking on carcinoma of the urinary bladder development, the minimum amount of data was extracted.Two investigators independently evaluated the quality of literature using the Newcastle-Ottawa Scale (NOS), and in case of disagreement, the primary investigator confirmed the quality. The scale was scored out of 9, and articles with a score of ≥7 were regarded as high quality, and articles with a score of >6 were included in the study.I2 values were used to quantify the heterogeneity of the study for analysis, with I2 < 50% indicating moderate heterogeneity and selection of a fixed-effects model and I2 ≥ 50% represents high levels of heterogeneity. I2 ≥ 50%, sensitivity analysis was performed one-by-one. Sensitivity analysis was performed to discover the origin of heterogeneity and the robustness of the data results. Egger's test was used to quantify publication bias and was considered statistically significant at p < 0.05, meaning that publication bias was present. Funnel plots were drawn and the distribution characteristics were observed to examine the publication bias of the included literature.The meta-analysis package of R language 4.1.0 software was used for data analysis. OR or RR values with 95% CI were used to describe the link between tea drinking and the risk of carcinoma of the urinary bladder. 357 literature studies were searched in PubMed, Embase, and Cochrane Library databases by keywords, and 11 literature studies were finally included for analysis through inclusion and exclusion criteria. The specific screening process is shown in The essential features of the incorporated studies are listed in Studies were conducted mainly in Western countries, with only one study conducted in China, and all included studies were retrospective studies using either questionnaires or a combination of questionnaires and interviews. 7,686 patients with carcinoma of the urinary bladder and 10,320 patients without cancer were included. Ten studies had NOS scores greater than 7, and they were considered high quality studies, and one study with a NOS score of 6 was considered lower quality but was still included in the analysis.I2 was 62%, indicating a high heterogeneity in the included literature, and hence a random effects model was used for the analysis. The results of the meta-analysis showed an OR of 1.02 with 95% CI of 0.93–1.11. The forest plot is shown in Eleven papers reported a link between tea drinking and the risk of carcinoma of the urinary bladder. The result of p = 0.4651), so there was no publication bias  induced oral cancer in golden gopher ; green aAl-Zalabani et al. showed in their article that a higher level of tea consumption was associated with lower risk of bladder cancer incidence. In addition, dose-response analyses showed a lower bladder cancer risk with increment of 100 ml of tea consumption per day .In summary, the results of this paper suggest that tea drinking may not lower the risk of carcinoma of the urinary bladder, but there are still some limitations of this study, mainly in the following aspects: (1) All included literature are retrospective case-control studies, and there are no randomized, double-blind, placebo-controlled studies, which would lower the reliability of the data in this study. (2) Most of the included studies considered the connection between tea and carcinoma of the urinary bladder risking general, without considering the type of tea and the amount of tea consumed, which prevented a more precise analysis of this study. (3) As there were no subgroup analyses of age, gender, and other adverse lifestyle habits in the included literature, the corresponding data could not be obtained for analysis in this study. Hence, high-quality randomized controlled placebo studies with large samples are needed to confirm whether tea drinking lowers the risk of carcinoma of the urinary bladder.


However, compared with CR alone, TRE plus CR exhibited no significant benefit on the blood pressure, glucose profile, and lipid profile. Subgroup analysis suggested that early TRE is more effective in weight loss  and improving fat mass  than delayed or broader TRE when combined with CR. Although the combination of TRE and CR can effectively decrease body weight, fat mass, and waist circumference, the long-term effects, particularly those on cardiometabolic risk in participants with chronic cardiovascular disease and diabetes, remain to be explored.The effect of time-restricted eating (TRE) has been summarized in previous studies, but its benefits in combination with calorie restriction (CR) still need to be determined. The present meta-analysis aimed to evaluate the efficacy of TRE with CR on weight loss and cardiometabolic risk. PubMed, Embase, Cochrane Library, and gray literature databases were searched from inception to October 18, 2022, for potential randomized controlled trial (RCT) studies based on predefined inclusion and exclusion criteria. Body weight and other cardiometabolic risk factors were described as weighted mean difference (WMD) with a 95% confidence interval (CI). Eight RCTs involving 579 participants were enrolled in the present analysis. The pooled results showed that TRE with CR reduced the body weight, fat mass, and waist circumference significantly (WMD: −1.40, 95% CI: −1.81 to −1.00, and I Obesity prevalence has climbed over the past few decades in most nations and has doubled in 73 countries . As a reWeight loss by lifestyle intervention has been established as fundamental to weight management . NotablyTime-restricted eating (TRE), a subtype of IF regimen that calls for a set window of time for eating and fasting within each 24-hour period, has grown in prominence as a creative and workable method of treatment for obesity and metabolic diseases . TRE eliTraditionally, TRE was commonly used for dietary intervention in mice laboratory experiments, and earlier animal studies have repeatedly identified that diet plays a vital role in weight loss and improving metabolic parameters . For insPrevious meta-analysis publications have investigated the advantages of TRE in various contexts using healthy individuals or participants who are overweight or obese –24. TRE https://inplasy.com/) under the record number INPLASY2022100082. The meta-analysis was performed in accordance with the outlines of the Preferred Reporting Items for Systematic Reviews and Meta-analysis Statement  [A protocol was developed and followed for all steps of the current systematic review and meta-analysis, and it was registered in INPLASY  .PubMed, Embase and Cochrane Library were searched from inception to October 18, 2022, for potentially relevant studies without restriction applied to language, publication year, or region using the following search terms: intervention  and outcome (blood pressure or diastolic pressure or systolic pressure or diastolic blood pressure or systolic blood pressure or glucose or insulin or homeostatic model assessment for insulin resistance or glucose or insulin or HOMA-IR or HOMA-β or cholesterol or triglyceride or triglycerides or Triacylglycerol or Triacylglycerols or plasma lipid or weight loss or weight losses or weight reduction or weight reductions). The search was updated on January 13, 2023. The complete search terms are described in detail in Supplementary Material. We manually scanned the reference lists of included papers to find gray literature. Furthermore, ClinicalTrials.gov and two gray literature databases were searched for relevant research (OpenGrey.eu and Greylit).The inclusion criteria were as follows: (1) study participants over 18 years of age; (2) participants assigned to TRE (for at least 12 h daily) associated with moderate  CR; (3) studies reporting outcomes including at least one of the body composition or cardiometabolic risk factors, such as weight loss, fat mass, waist circumference (WC), systolic blood pressure (SBP), diastolic blood pressure (DBP), glucose, insulin, HOMA-IR, HOMA-β, total cholesterol (TC), triglycerides (TG), low-density lipoprotein (LDL); (4) studies with RCTs. Moreover, studies that did not specifically mention TRE and CR but described treatments containing TRE and CR components were considered. Studies enrolled participants taking part in additional weight loss therapies were excluded. This meta-analysis excluded studies without sufficient data and individuals with acute or chronic illnesses that would affect the TRE treatment. If studies comprised the same trials, we analyzed the study with the most extended duration or comprehensive information.Study selection was performed in two phases: an initial title and abstract screening followed by a complete text examination of papers for suitability in this research. Two review authors (JCS and ZTT) independently assessed the eligibility of the papers, and any discrepancies were settled by a third investigator (GQ). The full texts of potentially eligible articles were obtained for further evaluation. Data extraction was performed systematically by two authors (CJH and CLZ) using data extraction sheets, and discrepancies were addressed by consensus. The extracted data included the first author, publication year, country, duration of follow-up, study design, sample size, demographic characteristics of the participants, mean weight, mean body mass index (BMI), body composition, fasting glucose, insulin, blood pressure, HOMA-IR, HOMA-β, and lipid profile. We reached out to the authors of articles that lacked relevant data.All outcomes were continuous variables, and thus, the mean changes and corresponding standard deviation (SD) values were extracted in both intervention and control groups. The changes in mean and SD were calculated using the correlation coefficient approach suggested in the Cochrane Handbook  if studiTwo reviewers (JCS and ZTT) independently evaluated the risk of bias in selected studies using the revised Cochrane risk of bias tool for randomized trials (ROB2) . The biaThe Grading of Recommendations Assessment, Development, and Evaluation (GRADE) framework  was used2 statistic was used to quantify the degree of heterogeneity between studies . Considering the likely high heterogeneity because of diverse clinical and methodological factors in included studies, the random-effects model of Dersimonian and Laird was used to calculate the pooled WMD with 95% CI for the TRE combined with CR and their effect on weight loss and cardiometabolic risk. Sensitivity analyses by sequential deletion of trials were used to investigate results with moderate or high levels of heterogeneity to determine the heterogeneity source.Stata Statistical Software version 16.0  was used for the analysis. Two-sided P values were evaluated for significance at an alpha level of 0.05. Differences between the final and baseline mean values of each outcome were reported as change values and analyzed. The effect size was determined by the weighted mean difference (WMD) between these differences. The IConsidering the different subtypes of TRE, subgroup analyses were performed based on broader TRE (unclear due to self-selective eating windows for ad libitum) with CR, early TRE (eTRE) with CR, and delayed TRE (dTRE) with CR. Subgroup analyses were also conducted to determine the subgroup difference after stratifying for daily fasting to eating ratios (16:8 vs. 14:10 vs. 12:12), mean baseline BMI (overweight vs. obesity), duration (short-term vs. long-term), and study location (Europe vs. South America vs. North America vs. Asia). Short-term study duration was defined as less than 12 weeks, whereas a period of 12 weeks or longer was deemed a long-term study duration. To evaluate potential publication bias, we assessed funnel plot asymmetry by visualization and performed a trim-and-fill analysis if publication bias was detected. Additionally, we used Egger’s tests to identify small-study effects.After removing duplicates, 1347 records were retrieved during the initial and updated search. The full texts of 105 papers were obtained for further assessment based on titles and abstract screening. Eight publications covered 579 participants and were qualified for data extraction and quantitative analysis , 30–36. All eight articles included individuals who were overweight or obese, 147 of whom were male. Only one study focused on participants with diabetes . StudiesA version of ROB2 for individually randomized, parallel-group trials was applied to evaluate seven parallel-arm designed studies, and the results are displayed in Fig. 2: 0%; Fig. 2: 0%; Fig. SP = 0.841).Eight studies , 30–36 w2: 0%; Fig. 2: 67.25%; Fig. 2: 0%).The changes in fat mass were recorded in five studies  , 33–36. 2: 0%; Fig. 2: 61.11%; Fig. 2: 47.49%).Four studies , 33–36 w2: 55.62%; Fig. 2: 0%). For insulin, the pooled analysis of four studies [2: 5.52%; Fig. 2: 63.50%; WMD: −31.70, 95% CI: −89.99 to 26.59, and I2: 0%, respectively; Fig. Six studies , 32–36 w studies , 34, 36 2: 0%; Fig. 2: 0%; Fig. 2: 0%; Fig. Changes in lipid profiles were reported by six studies , 33–36, 2: 0%) and −0.74 kg , the weight was reduced significantly in the 16:8 . Conversely, in overweight (mean baseline BMI ≥ 25 and <30 kg/m2) participants, weight loss was nonsignificant, and similar outcomes were observed in the fat mass and WC.TRE plus CR effectively reduced body weight  suggested that studies conducted in Europe and North America found beneficial effects of TRE with CR on weight loss  of intervention . The funnel plot and Egger’s test revealed neither publication bias nor small-study effects on body weight in the selected papers. One study presented a low risk of bias, whereas seven studies raised some concerns. The GRADE evaluation rated six of the twelve outcomes from the current study as low quality, and the remaining six were classified as very low quality.The present study result matched the earlier trial’s conclusions that proposed TRE with CR as a successful measurement tool to improve body composition . SeveralSubgroup analysis revealed increased body weight loss and fat mass reduction tendencies in participants with eTRE plus CR intervention compared with CR alone, but no body weight or fat mass benefits was found in the subgroups of dTRE plus CR, broader TRE plus CR. The analysis results should be interpreted cautiously because dTRE was only exploited in one study . The subSubgroup analysis based on diverse daily fasting-to-eating ratios demonstrated that TRE combined with CR had significant positive effects on body weight if the fasting window was 14 h or more, whereas no significant difference was discovered in fat mass and WC among any subgroups, except for the 14:10 group in WC . HoweverThe TRE regimen did not significantly benefit blood pressure compared with the CR regimens. The sensitivity analysis of DBP detected a moderate heterogeneity when the study by Lin et al.  was remoThe current meta-analysis showed that TRE did not provide extra benefits on glycemic and lipid profiles compared with daily CR. Sensitivity analysis showed a similar result in glucose levels between groups when the study causing heterogeneity was excluded. As mentioned in the current review, isocaloric TRE, particularly in individuals with prediabetes, improves fasting insulin and insulin resistance independent of weight loss , but witWe acknowledge that the present study has some limitations. The main limitation of the present meta-analysis was the low or very low quality evidence of study outcomes classified by the GRADE tool, which was primarily attributed to the risk of bias that the nature of behavioral intervention by a fixed ratio of fasting and eating periods, preventing it from blinding the participants. Nevertheless, the study results were all objective measures that were slightly affected by subjective dimension and influenced the outcomes mildly regardless of whether the participants were informed of allocation results. Second, several results displayed varied heterogeneity because of the TRE subtype, various fasting and eating duration ratios, and different baseline body weights. Subgroup analyses were carried out to investigate the combined effects of TRE and CR on specific subgroups. Meanwhile, sensitivity analysis was also conducted to determine the source of heterogeneity in outcomes with substantial and high heterogeneity. Third, the representativeness of participants was impaired by rigorous inclusion criteria, with several trials eliminating individuals under treatment for diabetes and cardiovascular disease. As a result, the findings cannot be used to generalize clinical participants, especially those with chronic diseases receiving treatment. The quality of evidence and dependability of the findings are expected to increase in future long-term studies with representativeness and a large sample of participants.Our systematic review and meta-analysis demonstrated that calorie-intake restriction with time restriction could significantly decrease body weight, fat mass, and WC. Although the combination of TRE and CR did not benefit cardiometabolic risk factors , the results should be interpreted with caution because of the specificity of the included population. The present study results highlight the need for well-designed, large-sample, and long-term studies to improve the evidence quality for the effect of TRE combined with CR on participants with chronic cardiovascular disease and diabetes.supplementary figuressupplemental tablesSpreadsheet for risk of bias assessment processsearch termsPRISMA checklist


Immune checkpoint inhibitors have revolutionized the treatment of malignancies. However, disproportionate enrollment among races and ethnicities places the generalizability of global trial results in doubt.In this systematic review, phase 3 randomized controlled trials investigating pembrolizumab in advanced cancers and providing subgroup analyses of Asian and non‐Asian participants were included. The primary and secondary effect measures were the mean differences (MDs) in the natural logarithms of the hazard ratios (HRs) for overall survival (OS) and progression‐free survival (PFS) between these two subgroups, respectively. We used random‐effects meta‐analysis to calculate the pooled ratios of HRs ) and implemented a meta‐regression analysis to identify significant covariates.p = 0.0391), favoring Asian participants, but no significant difference was found in PFS . Both linear meta‐regression analyses revealed an open‐label design as a crucial covariate, which indicated more benefits for non‐Asian participants.A total of 17 and 11 trials were included in the meta‐analyses of OS and PFS, respectively. These trials included 2732 (25.49%) Asian and 7000 (65.32%) non‐Asian participants in the OS analysis and 1438 (22.5%) Asian and 4129 (64.61%) non‐Asian participants in the PFS analysis. The pooled ratio of HRs for OS was 0.87 (95% CI: 0.76–0.99; Compared with non‐Asian patients, Asian patients with advanced cancers may derive superior OS benefits from pembrolizumab. Although the results warrant further exploration, this meta‐analysis provides insight into clinical research design. Clinical trials have repeatedly demonstrated the overall survival (OS) benefits of ICIs in patients with cancer of various types, and health authorities worldwide have granted regular approval for several ICIs, including a cytotoxic T‐lymphocyte antigen 4 (CTLA4) inhibitor (ipilimumab); programmed cell death 1 (PD‐1) inhibitors ; and programmed cell death ligand 1 (PD‐L1) inhibitors . Among these, pembrolizumab is the most widely indicated and is anticipated to be the most sold drug in 2023.Patients from different racial and ethnic groups experience different epidemiology, management, and survival outcomes in various cancers.Racial and ethnic disparities in global trial enrollment could result in disproportionately more research on Western patients than on Eastern patients. Most trial participants are recruited from North America or Western Europe, and few participants are recruited from Asia.2This systematic review and meta‐analysis followed the Preferred Reporting Items for Systematic Reviews and Meta‐analyses (PRISMA) guidelines.2.1Two authors, SH Peng and YS Lu, independently searched the medical literature databases of PubMed, Cochrane Library, Embase, and Web of Science for relevant articles using the terms “pembrolizumab” and “randomized controlled trial.” The details of the search strategies used for each database are provided in Table 2.2SH Peng and YS Lu independently extracted and verified relevant information from the published manuscripts and supplementary appendices of 26 selected studies to obtain the following metadata: trial name, first author, publication year, study design , cancer type, setting (first‐line treatment or beyond), experimental treatment strategy , criteria for PD‐L1 expression, primary endpoints, patient numbers, and demographic characteristics . The selected cutoffs for PD‐L1 expression agreed with the primary analysis by statistical testing hierarchy, available demographic characteristics, or label indications Table .The experimental treatment strategies were categorized as (1) monotherapy versus standard of care (SOC), (2) monotherapy versus best supportive care (BSC), (3) add‐on to chemotherapy (ChT) versus SOC, (4) add‐on to multikinase inhibitor (MKI) versus SOC; and (5) combined therapy with MKI versus standard ChT. Cancer types were classified into nine groups: (1) NSCLC, (2) hepatocellular carcinoma (HCC), (3) squamous cell carcinoma of the aerodigestive tract, (4) esophageal and gastric adenocarcinoma, (5) breast cancer, (6) renal cell carcinoma (RCC), (7) melanoma, (8) urothelial carcinoma (UC), and (9) miscellaneous cancers. We also collected the estimated hazard ratios (HRs) with 95% CIs for OS and progression‐free survival (PFS) for the total populations, Asian subgroups, and non‐Asian subgroups.2.3p ≤ 0.05 was considered statistically significant. The primary and secondary outcomes were OS and PFS, respectively. The mean difference (MD) in the natural logarithms of the HRs for OS or PFS between the Asian and non‐Asian subgroups was determined as the effect measure to compare the efficacy of pembrolizumab in the Asian and non‐Asian subgroups, as the following equation:We used the metafor package (version 3.8‐1) in R 4.2.1  to perform meta‐analyses and meta‐regression analyses.Q test and the I2 statistic, where a p < 0.15 in the Q test or I2 of >50% indicated substantial heterogeneity.In forest plots, the estimated pooled ratios of HRs ) for OS and PFS for Asian to non‐Asian patients were obtained through random‐effects meta‐analysis with Knapp–Hartung adjustment. The heterogeneity among the selected studies was evaluated using the chi‐square I2 or substantive knowledge suggested substantial heterogeneity among the analyzed studies, a fixed‐effects linear meta‐regression analysis of MDs was fitted to the metadata through the weighted least‐squares method to identify the relevant covariate that might account for the observed heterogeneity. If the residual heterogeneity remained statistically significant, a mixed‐effects linear meta‐regression analysis of the MDs was performed with added random effects to account for unknown sources of heterogeneity.If the statistical tests for heterogeneity and the cubic smoothing splines) in the VGAM package in R to fit the GAMs for continuous responses and then used the plotvgam function of the same package to draw GAM plots to visualize the linear or nonlinear effects of continuous covariates.Simple and multiple generalized additive models (GAMs) of the MDs were constructed and used to draw GAM plots for detecting the nonlinear effects of continuous covariates and identifying the appropriate cutoffs for continuous covariates, if necessary, during the stepwise variable selection procedure. We used the vgam function with the default values of the smoothing parameters  for forward and backward steps) was implemented to obtain the candidate variables for the final linear meta‐regression model. The coefficient of determination, R2, for the final model is the square of the Pearson's correlation coefficient between the observed and predicted response values. Finally, regression diagnostics were performed, including multicollinearity, residual analysis, influential studies identification, and publication bias assessments.Variable selection, goodness‐of‐fit assessment, and regression diagnostics were used in the meta‐regression analysis to ensure the quality of the results. Specifically, with the aid of the likelihood ratio test, a stepwise variable selection procedure (including iterations between the 33.1n = 3)n = 2).n = 26), three contained 3 trial arms .n = 17, m = 19 for OSn = 11, m = 12 for PFSThe flow diagram in Figure 3.2n = 18, 69.23%),n = 2),n = 1),n = 3),n = 2).Table 3.3n = 26). Of these, 8814 received pembrolizumab, and 6739 received control treatments. Among all patients, 23.01% (3579) were Asian  revealed that pembrolizumab had a statistically significant OS benefit in the total populations . The pooled ratio of HRs for OS between the Asian and non‐Asian subgroups (m = 19) also revealed a statistically significant difference . This value was 0.4897 higher in the trials using add‐on pembrolizumab (to ChT or MKI) or combination pembrolizumab‐MKI with an open‐label design , 0.4257 higher if the percentage of ECOG PS scores of 0 was ≤50.28% in the experimental arm , and 0.2787 higher if the percentage of men was ≤81.92% in the experimental arm .Table Q–Q plot of the regression residuals indicated that the assumption of normality was not violated  revealed that the efficacy of pembrolizumab in PFS was statistically significant in the total populations . The pooled ratio of HRs for PFS between the Asian and non‐Asian subgroups (m = 12) did not reach statistical significance . This value was 0.2948 higher in open‐label trials .Table Q‐Q plot of the regression residuals indicated that the assumption of normality was not violated . However, the efficacy in PFS did not significantly differ between the Asian and non‐Asian subgroups . Generally, OS is a relatively solid endpoint in oncology trials compared to PFS. Consistent with our analysis results .In this systematic review, approximately 25% of the patients in the formal analyses of OS and PFS were Asian . Similar to a previous report,s Figure , the magEGFR) mutations and disease progression after platinum‐based ChT and an EGFR tyrosine kinase inhibitor were eligible and constituted 8.8% of the patients in the pembrolizumab monotherapy arm and 7.6% of the patients in the docetaxel arm. Moreover, a meta‐analysis demonstrated that pembrolizumab significantly prolonged OS for patients with wild‐type EGFR, not mutant EGFR.EGFR mutations being the most prevalent in Asian patients.According to the regression diagnostics of the two models Figure , KEYNOTEm = 17) used an open‐label design. The use of placebos may help reduce bias, but placebo production can be challenging and time‐consuming. The accrual rate may be influenced by the placebo design, and accrual projections are crucial, particularly if competitive studies are being conducted simultaneously. Consequently, objective and reliable outcome measurements, independent outcome adjudications , and sensitivity analyses with censoring rules could be employed to minimize this risk. These practical issues are unavoidable in trial design. Further investigation is warranted to understand the relationship between an open‐label design and any observed differences between Asian and non‐Asian patients.In RCTs, masking is crucial to ensure an unbiased estimate of the treatment effect; an open‐label design can introduce bias and exaggerate the results.p = 0.0085 and 0.0411, respectively). However, sex was discovered in another meta‐analysis not to be significantly associated with the efficacy of ICIs.The strengths of this meta‐analysis include its rigorous data extraction and thorough meta‐regression analysis; these provide comprehensive assessments of the relative efficacy of pembrolizumab for Asian participants and insight into global trial design. These encouraging results may help promote the expansion of global trials in Asia. The inaccessibility of individual patient data is a major limitation, rendering comparisons of demographic and disease characteristics between subgroups challenging. Because of restricted data sources, the efficacy for Asian patients was not compared to other subdivided races and ethnicities. In the meta‐regression model for OS, the lower proportions of ECOG PS scores of 0 (≤50.28%) and men (≤81.92%) in the experimental arms resulted in superior OS benefits for the non‐Asian subgroups ; formal analysis (supporting); investigation (lead); software (supporting); validation (supporting); visualization (lead); writing – original draft (lead). Ching‐Hung Lin: Investigation (supporting); writing – review and editing (supporting). I‐Chun Chen: Investigation (supporting); writing – review and editing (supporting). Ying‐Chun Shen: Investigation (supporting); writing – review and editing (supporting). Dwan‐Ying Chang: Investigation (supporting); writing – review and editing (supporting). Tom Wei‐Wu Chen: Investigation (supporting); writing – review and editing (supporting). Shu‐Min Huang: Project administration (supporting). Fu‐Chang Hu: Formal analysis (lead); investigation (lead); methodology (lead); software (lead); visualization (lead); writing – review and editing (supporting). Yen‐Shen Lu: Conceptualization (lead); data curation (lead); formal analysis (lead); funding acquisition (lead); investigation (lead); methodology (lead); resources (lead); supervision (lead); validation (lead); writing – review and editing (lead).This work was supported by the National Science and Technology Council, Taiwan (MOST 110‐2314‐B‐002‐218).Ching‐Hung Lin reports honoraria from AstraZeneca, Eli Lilly, Novartis, and Pfizer, consulting for AstraZeneca, Eli Lilly, Novartis, and Pfizer. Tom Wei‐Wu Chen reports honoraria from AstraZeneca, Daiichi Sankyo, Eisai, Eli Lilly, Novartis, and Roche, consulting for AstraZeneca, Blueprint Medicines, Daiichi Sankyo, Eisai, and Roche, and research funding from Eisai and Epizyme. Yen‐Shen Lu reports honoraria from AstraZeneca, Daiichi Sankyo, Eisai, EuroPharma, Eli Lilly, Merck Sharp & Dohme, Novartis, Pfizer, and Roche, consulting for Eli Lilly, Novartis, Pfizer, and Roche, and research funding from AstraZeneca, Merck Sharp & Dohme, and Novartis. The remaining authors declare no conflicts of interest.The funder did not play a role in the design of the study; the collection, analysis, and interpretation of the data; the writing of the manuscript; and the decision to submit the manuscript for publication.The authors of this study are solely responsible for the interpretation and presentation of the data.Results in this manuscript have been presented in part on a poster at the 2022 Taipei International Breast Cancer Symposium and selected for online publication abstract by the 2023 ASCO Annual Meeting.Appendix S1.Click here for additional data file.


Gut microbiota imbalances have been suggested as a contributing factor to atrial fibrillation (AF), but the causal relationship is not fully understood.To explore the causal relationships between the gut microbiota and AF using Mendelian randomization (MR) analysis.Summary statistics were from genome-wide association studies (GWAS) of 207 gut microbial taxa  (the Dutch Microbiome Project) and two large meta-GWASs of AF. The significant results were validated in FinnGen cohort and over 430,000 UK Biobank participants. Mediation MR analyses were conducted for AF risk factors, including type 2 diabetes, coronary artery disease (CAD), body mass index (BMI), blood lipids, blood pressure, and obstructive sleep apnea, to explore the potential mediation effect of these risk factors in between the gut microbiota and AF.Eubacterium ramulus  adjusted p-value = 0.023) and genus Holdemania . Genus Holdemania was associated with incident AF risk in the UK Biobank. The proportion of mediation effect of species Eubacterium ramulus via CAD was 8.05% , while the proportion of genus Holdemania on AF via BMI was 12.01% .Two microbial taxa causally associated with AF: species This study provided genetic evidence to support a potential causal mechanism between gut microbiota and AF and suggested the mediation role of AF risk factors.The online version contains supplementary material available at 10.1186/s12933-023-02045-6. Atrial fibrillation (AF) is a supraventricular tachyarrhythmia with uncoordinated atrial electrical activation and ineffective atrial contraction consequently, which affects adults globally, with an estimated prevalence between 2% and 4% . PatientSeveral observational cohort studies have suggested that imbalances in gut microbiota composition may contribute to AF. These studies have investigated the differences in gut microbiota between patients with AF and control subjects, as well as the variations in gut microbiota among AF patients with different subtypes, including persistent and paroxysmal AF and AF with different duration –10. The Mendelian randomization (MR) is an analysis methodology that uses genetic variants associated with a proposed risk factor as surrogates to determine the causal effect of that exposure on an outcome of interest. This approach mimics the randomization process used in randomized controlled trials . Large-sIn the present study, we evaluated the causal effects of gut microbiota and AF using a two-sample MR study design. We prioritized two gut microbial taxa that have potential causal effects on AF and validated our findings in independent datasets using either summary-level or individual-level data. We also performed mediation MR analysis to identify the mediation effects of the risk factors of AF in between the associations of gut microbiota and AF. Our results demonstrated a potential causal association between specific gut microbiota and AF and suggested that several AF risk factors play a mediation role in these associations.The study design is illustrated in Fig. We selected summary data from a GWAS of 7,738 individuals of European descent from the Dutch Microbiome Project (DMP) to obtain species-level data on gut microbiota and own as strong statistical power as possible (Supplementary Table − 5) defined in the original study and had an effect allele frequency (EAF) > 0.01. The threshold P < 1 × 10− 5 for instrumental variables inclusion of gut microbiota is less stringent, it was selected to maximize the amount of instrument and the genetic variance explained by genetic predictors, a criterion that has been used in several MR studies related to gut microbiome previously [2 < 0.001 within ± 10,000 kilobases (kb) distance using the 1000 Genomes European reference panel separately. When palindromic SNPs were present, the forward strand alleles were inferred using allele frequency information. Additionally, we used proxies of SNPs as substitutes with r2 ≥ 0.8 if the SNPs could not be found in the corresponding outcome GWAS summary data. Then we calculated the F-statistics of all SNP in our analysis.We used genetic variants of microbial taxa that passed the GWAS testing P value threshold  for individual gut microbial taxa for each participant. We selected SNPs strongly associated with these microbial taxa from the DMP cohort’s GWAS. These same SNPs served as instrumental variables in our two-sample MR framework. The assigned weights for each SNP were determined based on their respective effect sizes, as obtained from the GWAS in DMP cohort.AF was defined based on the occurrence of one or more International Classification of Disease, 10th Revision  codes or 9th Revision (4273) codes in electronic health records from hospital inpatient admissions or the death register. Hospital inpatient data were censored on Sept 30, 2021 (England), July 31, 2021 (Scotland), and Feb 28, 2018 . Follow-up for all participants started from the date of recruitment to the date when AF was diagnosed, the date of death, or the date of loss to follow-up, whichever occurred first. Prevalent AF was defined as any event with a date of occurrence before and on the participant’s first visit for recruitment into the study and was excluded from the survival analysis. Incident AF was defined as an event occurring after excluding baseline AF history and documented after the recruitment visit.The Cox proportional hazards model was used to investigate the relationship between wt-GRS and incident AF events after adjustment for age, sex, genotype measurement batch, assessment center, and the top 40 genetic principal components. The proportional hazard assumption was tested using the Schoenfeld residual method, and did not show evidence for violation of the proportional hazard assumptions. To account for possible influence of selective survival, we estimated the cumulative incidence of AF from competing-risks regression based on Fine-Gray models while taking into account death as a competing risk event.To understand potential causal mechanisms between gut microbial taxa and AF, we conducted mediation MR analyses for AF risk factors  or R platform (version 4.2.1). The “TwoSampleMR”, “Mendelian Randomization” packages were used for statistical analyses.In this study, we report MR findings according to the STROBE-MR (Strengthening the Reporting of Mendelian Randomization Studies) guidelines  of 1.08 and a 95% confidence interval (CI) of 1.04 to 1.12 . This result was supported by the MR sensitivity analyses of MR-PRESSO and weighted median. The other significant taxon was genus Holdemania . There was no evidence of directional pleiotropy (Egger intercept P = 0.111) and heterogeneity of genetic instruments  in our analysis    ; genus Holdemania was significantly associated with BMI   Fig. . The resEubacterium ramulus via CAD was 8.05% , while the mediation effect of genus Holdemania on the risk of AF via BMI was 12.01%  .The proportion of the mediation effect of species The main findings of this study are summarized in Fig. Eubacterium ramulus and genus Holdemania, which were significantly associated with the risk of AF. To the best of our knowledge, this is the first study to show a link between these two gut microbial taxa and AF. Furthermore, CAD might mediate the effect of Eubacterium ramulus, while BMI mediates the effect of Holdemania on AF. Our analysis provided genetic evidence for a potential causal relationship between specific gut microbiota and AF and suggested a potential mediating pathway of gut microbiota, risk factors of AF, and the AF.In the present large-scale and comprehensive MR study, we identified two gut microbial taxa, species Eubacterium ramulus, known as a kind of flavonoid-degrading intestinal bacterium, can convert members of various flavonoid subclasses, such as flavonols, flavanonols, flavones, flavanones, and isoflavones into phenolic acids [Eubacterium ramulus may contribute to the increased risk of AF by partially reducing the bioactivity of flavonoids through its degradative ability, resulting in a diminished protective effect of dietary flavonoids. Our mediation analysis revealed that CAD mediates the effect of Eubacterium ramulus on AF. This is the first study to report a significant association between the species Eubacterium ramulus and CAD. Previous studies have demonstrated that CAD is a significant risk factor for AF [Species ic acids . Flavonoic acids –40. Specr for AF , 41. OurHoldemania and AF, previous studies have linked genus Holdemania with a number of health issues. Genus Holdemania is associated with clinical indicators of impaired lipid metabolism [Holdemania. [Holdemania is positively associated with gout disease [Holdemania is enriched in the feces of Parkinson’s disease patients [Holdemania may play a negative role in overall health and is a reflection of lifestyle. In our mediation analysis, we observed that BMI played a mediating role between genus Holdemania and AF. On one hand, this finding is consistent with previous studies that have established a significant association between BMI and AF [Holdemania and pregestational BMI in pregnant women, providing further evidence for this potential mediation pathway [Holdemania is involved in the degradation of mucin, the major component of the gut mucus barrier. Excessive degradation of mucin can promote intestinal barrier damage and trigger a systemic inflammatory response, which may partially account for its association with these diseases [Even though there is no direct evidence of the relationship between genus tabolism . In physdemania. . Additio disease  and is f disease  Furthermpatients . Its abupatients  and highpatients . These fI and AF . On the  pathway . Previoudiseases .Eubacterium ramulus and genus Holdemania and AF, the evidence remains limited and of relatively low quality. Therefore, in the future, larger clinical studies and animal and cellular mechanism studies are warranted to confirm the health effects and mechanisms of these bacteria.Overall, while some research supports the link between species Previous MR studies have investigated the relationship between gut microbiota and AF –53. The Our study has several key strengths. Firstly, we performed MR analysis using the largest European population-based GWAS study of AF and validated it in an independent population. We included nearly all current available AF GWAS studies. Secondly, we used the species-level analysis to define gut microbiota taxa, which is more conducive to the next step of animal experiments and mechanism research. Lastly, we conducted a mediation analysis to help understand the potential mechanism pathways of association between gut microbiota and AF.− 5 as the genome-wide significance level to define significant associated genetic loci, as the primary GWAS and other MR of gut microbiota used. Nevertheless, the IV is strong and qualified for the following analysis. Secondly, previous studies have pointed out certain differences in gut dysbiosis between AF subtypes [https://sb452.shinyapps.io/overlap/). The results indicated that our findings were unlikely to be biased by weak instruments. Fourthly, though several approaches were conducted to assess and adjust for potential heterogeneity or pleiotropic effects, we could not completely rule out the influence of unknown heterogeneity or pleiotropic effects. Lastly, as our analysis was primarily conducted in European populations, the results should be cautiously generalized to other ethnic populations, as there may be ethnicity-specific associations between host genomes and the gut microbiome.Several limitations of our study should be acknowledged. Firstly, the sample size of the GWAS summary data for species-level gut microbiome taxa was the largest one to date, it may not have been sufficient to detect all potential causal relationships given the high heterogeneity of the gut microbiota between populations. We used a P value of 1 × 10subtypes , 8. Howesubtypes . NeverthIn this MR study, we identified two gut microbial taxa that have a potential causal effect on AF. Our findings provide genetic evidence that changes in the gut microbiota may be a significant predisposing factor for AF occurrence. These results offer new insights into AF pathophysiology and identify potential therapeutic targets for AF. Further research is needed to confirm these findings and to understand the underlying mechanisms involved.Below is the link to the electronic supplementary material.Supplementary Material 1Supplementary Material 2