title: Exploring causal associations of alcohol with cardiovascular and metabolic risk factors in a Chinese population using Mendelian randomization analysis.
abstract: Observational studies suggest that moderate alcohol consumption may be protective for cardiovascular disease, but results may be biased by confounding and reverse causality. Mendelian randomization, which uses genetic variants as proxies for exposures, can minimise these biases and therefore strengthen causal inference. Using a genetic variant in the ALDH2 gene associated with alcohol consumption, rs671, we performed a Mendelian randomization analysis in 1,712 diabetes cases and 2,076 controls from Nantong, China. Analyses were performed using linear and logistic regression, stratified by sex and diabetes status. The A allele of rs671 was strongly associated with reduced odds of being an alcohol drinker in all groups, but prevalence of alcohol consumption amongst females was very low. The A allele was associated with reduced systolic and diastolic blood pressure and decreased total and HDL cholesterol in males. The A allele was also associated with decreased triglyceride levels, but only robustly in diabetic males. There was no strong evidence for associations between rs671 and any outcomes in females. Our results suggest that associations of alcohol consumption with blood pressure and HDL-cholesterol are causal. Alcohol also appeared to have adverse effects on triglyceride levels, although this may be restricted to diabetics.
authors.affiliation: MRC Integrative Epidemiology Unit (IEU) at the University of Bristol, Oakfield House, Oakfield Grove, Bristol, UK.|UK Centre for Tobacco and Alcohol Studies and School of Experimental Psychology, University of Bristol, Bristol, BS8 1TU, UK.
authors.forename: Amy E
authors.initials: AE
authors.lastname: Taylor
authors.affiliation: Department of Epidemiology &Biostatistics at Nanjing Medical University School of Public Health, 818 East Tianyuan Rd, Nanjing 211166, P.R. China.|Department of Chronic Non-communicable Disease Control, Zhejiang Provincial Center for Disease Control and Prevention, 3399 Binsheng Rd, Hangzhou 310053, P.R. China.
authors.forename: Feng
authors.initials: F
authors.lastname: Lu
authors.affiliation: MRC Integrative Epidemiology Unit (IEU) at the University of Bristol, Oakfield House, Oakfield Grove, Bristol, UK.|School of Social and Community Medicine, University of Bristol, Oakfield House, Oakfield Grove, Bristol, BS8 2BN, UK.
authors.forename: David
authors.initials: D
authors.lastname: Carslake
authors.affiliation: Department of Epidemiology &Biostatistics at Nanjing Medical University School of Public Health, 818 East Tianyuan Rd, Nanjing 211166, P.R. China.
authors.forename: Zhibin
authors.initials: Z
authors.lastname: Hu
authors.affiliation: Department of Epidemiology &Biostatistics at Nanjing Medical University School of Public Health, 818 East Tianyuan Rd, Nanjing 211166, P.R. China.|Department of Chronic Non-communicable Disease Control, Wuxi Center for Disease Control and Prevention, 499 Jincheng Rd, Wuxi 214023, P.R. China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Qian
authors.affiliation: Department of Epidemiology &Biostatistics at Nanjing Medical University School of Public Health, 818 East Tianyuan Rd, Nanjing 211166, P.R. China.
authors.forename: Sijun
authors.initials: S
authors.lastname: Liu
authors.affiliation: Department of Epidemiology &Biostatistics at Nanjing Medical University School of Public Health, 818 East Tianyuan Rd, Nanjing 211166, P.R. China.
authors.forename: Jiaping
authors.initials: J
authors.lastname: Chen
authors.affiliation: Department of Epidemiology &Biostatistics at Nanjing Medical University School of Public Health, 818 East Tianyuan Rd, Nanjing 211166, P.R. China.
authors.forename: Hongbing
authors.initials: H
authors.lastname: Shen
authors.affiliation: MRC Integrative Epidemiology Unit (IEU) at the University of Bristol, Oakfield House, Oakfield Grove, Bristol, UK.|School of Social and Community Medicine, University of Bristol, Oakfield House, Oakfield Grove, Bristol, BS8 2BN, UK.
authors.forename: George Davey
authors.initials: GD
authors.lastname: Smith
mesh_terms: D000328:Adult; D000368:Aged; D000428:Alcohol Drinking; D000444:Aldehyde Dehydrogenase / Q000235:genetics*; D000071396:Aldehyde Dehydrogenase, Mitochondrial; D000483:Alleles; D044466:Asian People / Q000235:genetics*; D001794:Blood Pressure; D016022:Case-Control Studies; D002681:China; D008076:Cholesterol, HDL / Q000097:blood; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000473:pathology*; D005260:Female; D006801:Humans; D016014:Linear Models; D016015:Logistic Models; D008297:Male; D057182:Mendelian Randomization Analysis; D008875:Middle Aged; D016017:Odds Ratio; D012307:Risk Factors; D012737:Sex Factors; D014280:Triglycerides / Q000097:blood
chemical_list: D008076:Cholesterol, HDL; D014280:Triglycerides; C096127:ALDH2 protein, human; D000444:Aldehyde Dehydrogenase; D000071396:Aldehyde Dehydrogenase, Mitochondrial