Sex as an effect modifier in the association between alcohol intake and gastric cancer risk

BACKGROUND The results of previous meta-analyses evaluating the association between the alcohol intake and gastric cancer risk have reported that a statistical significance only for men.AIM To investigate the different association between alcohol intake and gastric cancer risk between men and women.METHODS The selection criteria included a prospective cohort study for evaluating alcohol intake and gastric cancer risk,with relative risks adjusted for potential confounders.Adjusted relative risk(RR)for the potential confounders and its 95%confidence interval(CI)in the highest vs lowest level were extracted from each study and a random-effects meta-analysis was conducted.Subgroup analyses by region,level of adjustment for smoking status,adjusting for body mass index,and year of publication were conducted.RESULTS A meta-analysis of all 27 cohorts showed that alcohol intake increased the risk of gastric cancer(summary RR=1.13,95%CI:1.04-1.23,I2=58.2%).Further,13 men’s cohorts had higher summary RR while maintaining statistical significance,and only seven women’s cohorts had no statistical significance.CONCLUSION The present review suggests that alcohol consumption increases the risk of gastric cancer in men.These findings showed that the sex variable in the association between alcohol intake and gastric cancer risk seemed to be an effect modifier with an interaction term.It is necessary to re-estimate follow-up outcomes after stratifying for sex.

Coffee consumption and risk of type 2 diabetes mellitus in Asians:A meta-epidemiological study of population-based cohort studies

BACKGROUND Previous systematic reviews have consistently reported that coffee consumption has a preventive effect on the occurrence of type 2 diabetes mellitus(T2DM).However,further evaluations between coffee consumption and the risk of T2DM in Asian populations are needed.AIM To conduct a meta-epidemiological study on systematic reviews evaluating the association between coffee consumption and the risk of T2DM in Asian people.METHODS The selection criterion was defined as a population-based prospective cohort study evaluating the association between coffee consumption and the risk of T2DM in Asian populations,reporting the adjusted relative risk(RR)and its 95%confidence interval(CI)for potential confounders.A fixed-effect model metaanalysis was applied to calculate the summary RR and its 95%CI in less than 50%of the I2 value indicating the level of heterogeneity.A two-stage fixed-effects doseresponse meta-analysis(DRMA)was performed to calculate the risk per unit dose(a cup per day).RESULTS A total of seven studies were selected in this meta-epidemiological study.The risk of T2DM in Asian populations was significantly reduced in the highest to the lowest dose group(summary RR=0.73,95%CI:0.66-0.82;I2 value=0.0%).The DRMA showed that drinking one cup of coffee per day reduced the risk of T2DM in Asian populations by 8%(RR=0.92,95%CI:0.90-0.95).CONCLUSION These findings support the conclusion that coffee consumption has a protective effect on the occurrence of T2DM in Asian men and women.

Human papillomavirus infection and gastric cancer risk: A metaepidemiological review

Gastric cancer(GC)is a multifactorial disease,and several modifiable risk factors have been reported.This review summarizes and interprets two previous quantitative systematic reviews evaluating the association between human papillomavirus(HPV)infection and GC risk.The results of two systematic reviews evaluating the same hypothesis showed a statistically significant difference in summary odds ratios and their 95%confidence intervals.Thus,it is necessary to conduct a subgroup analysis of Chinese and non-Chinese studies.Additional meta-analyses that control for heterogeneity are required.Reanalysis showed that all the Chinese studies had statistical significance,whereas the nonnational studies did not.The funnel plot asymmetry and Egger's test confirmed publication bias in the Chinese studies.In addition,the proportion of HPVpositive cases in Chinese studies was 1.43 times higher than that in non-Chinese studies and 2.81 times lower in controls.Therefore,the deduced evidence is currently insufficient to conclude that HPV infection is associated with GC risk.

Use of oral contraceptives and risk of pancreatic cancer in women:A recalculated meta-analysis of prospective cohort studies

In a recent systematic review and meta-analysis of observational studies,the author found potential errors in the selection and extraction processes.The recalculated summary relative risks and the results of a dose-response metaanalysis showed that oral contraceptive use may not be associated with the risk of pancreatic cancer in women.