Dataset Information

Is smoking heaviness causally associated with alcohol use? A Mendelian randomization study in four European cohorts.

ABSTRACT: Background:Observational studies have shown that tobacco and alcohol use co-occur, but it is not clear whether this relationship is causal. Methods:Using data from the Avon Longitudinal Study of Parents and Children (ALSPAC) and UK Biobank, we used observational methods to test the hypothesis that smoking heaviness increases alcohol consumption. Mendelian randomization (MR) analyses were then used to test the causal relationship between smoking heaviness and alcohol consumption using 55 967 smokers from four European studies [ALSPAC, The Nord-Trøndelag Health Study (HUNT), the Copenhagen General Population Study (CGPS) and UK Biobank]. MR analyses used rs1051730/rs16969968 as a genetic proxy for smoking heaviness. Results:Observational results provided evidence of an association between cigarettes per day and weekly alcohol consumption (increase in units of alcohol per additional cigarette smoked per day = 0.10, 95% confidence interval (CI) 0.05 to 0.15, P ? 0.001 in ALSPAC; and 0.48, 95% CI 0.45 to 0.52, P ? 0.001 in UK Biobank). However, there was little evidence for an association between rs1051730/rs16969968 and units of alcohol consumed per week across ALSPAC, HUNT, CGPS and UK Biobank (standard deviation increase in units of alcohol per additional copy of the risk allele = -0.004, 95% CI -0.023 to 0.016, P=0.708, I2 = 51.9%). We had 99% and 88% power to detect a change of 0.03 and 0.02 standard deviation units of alcohol per additional copy of the risk allele, respectively. Conclusions:Previously reported associations between smoking and alcohol are unlikely to be causal, and may be the result of confounding and/or reverse causation. This has implications for public health research and intervention research.

SUBMITTER: Taylor M

PROVIDER: S-EPMC6124618 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Is smoking heaviness causally associated with alcohol use? A Mendelian randomization study in four European cohorts.

Taylor Michelle M Rode Line L Bjørngaard Johan J Taylor Amy E AE Bojesen Stig E SE Åsvold Bjørn O BO Gabrielsen Maiken E ME Lewis Glyn G Nordestgaard Børge G BG Romundstad Pål R PR Hickman Matthew M Munafò Marcus R MR

International journal of epidemiology 20180801 4

<h4>Background</h4>Observational studies have shown that tobacco and alcohol use co-occur, but it is not clear whether this relationship is causal.<h4>Methods</h4>Using data from the Avon Longitudinal Study of Parents and Children (ALSPAC) and UK Biobank, we used observational methods to test the hypothesis that smoking heaviness increases alcohol consumption. Mendelian randomization (MR) analyses were then used to test the causal relationship between smoking heaviness and alcohol consumption us ...[more]

PMID: 29509885

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Project description:BackgroundAlterations in the brain cortical structures of patients with chronic kidney disease (CKD) have been reported; however, the cause has not been determined yet. Herein, we used Mendelian randomization (MR) to reveal the causal effect of kidney damage on brain cortical structure.MethodsGenome-wide association studies summary data of estimated glomerular filtration rate (eGFR) in 480,698 participants from the CKDGen Consortium were used to identify genetically predicted eGFR. Data from 567,460 individuals from the CKDGen Consortium were used to assess genetically determined CKD; 302,687 participants from the UK Biobank were used to evaluate genetically predicted albuminuria. Further, data from 51,665 patients from the ENIGMA Consortium were used to assess the relationship between genetic predisposition and reduced eGFR, CKD, and progressive albuminuria with alterations in cortical thickness (TH) or surficial area (SA) of the brain. Magnetic resonance imaging was used to measure the SA and TH globally and in 34 functional regions. Inverse-variance weighted was used as the primary estimate whereas MR Pleiotropy RESidual Sum and Outlier, MR-Egger and weighted median were used to detect heterogeneity and pleiotropy.FindingsAt the global level, albuminuria decreased TH (β = -0.07 mm, 95% CI: -0.12 mm to -0.02 mm, P = 0.004); at the functional level, albuminuria reduced TH of pars opercularis gyrus without global weighted (β = -0.11 mm, 95% CI: -0.16 mm to -0.07 mm, P = 3.74×10-6). No pleiotropy was detected.InterpretationKidney damage causally influences the cortex structure which suggests the existence of a kidney-brain axis.FundingThis study was supported by the Science and Technology Planning Project of Guangdong Province (Grant No. 2020A1515111119 and 2017B020227007), the National Key Research and Development Program of China (Grant No. 2018YFA0902803), the National Natural Science Foundation of China (Grant No. 81825016, 81961128027, 81772719, 81772728), the Key Areas Research and Development Program of Guangdong (Grant No. 2018B010109006), Guangdong Special Support Program (2017TX04R246), Grant KLB09001 from the Key Laboratory of Malignant Tumor Gene Regulation and Target Therapy of Guangdong Higher Education Institutes, and Grants from the Guangdong Science and Technology Department (2020B1212060018).

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Dataset Information

Is smoking heaviness causally associated with alcohol use? A Mendelian randomization study in four European cohorts.

Publications

Is smoking heaviness causally associated with alcohol use? A Mendelian randomization study in four European cohorts.

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