Are there non-linear relationships between alcohol consumption and long-term health?: a systematic review of observational studies employing approaches to improve causal inference
BACKGROUND: Research has long found 'J-shaped' relationships between alcohol consumption and certain health outcomes, indicating a protective effect of moderate consumption. However, methodological limitations in most studies hinder causal inference. This review aimed to identify all observational studies employing improved approaches to mitigate confounding in characterizing alcohol-long-term health relationships, and to qualitatively synthesize their findings.
METHODS: Eligible studies met the above description, were longitudinal (with pre-defined exceptions), discretized alcohol consumption, and were conducted with human populations. MEDLINE, PsycINFO, Embase and SCOPUS were searched in May 2020, yielding 16 published manuscripts reporting on cancer, diabetes, dementia, mental health, cardiovascular health, mortality, HIV seroconversion, and musculoskeletal health. Risk of bias of cohort studies was evaluated using the Newcastle-Ottawa Scale, and a recently developed tool was used for Mendelian RandomizationThe basic idea of the Mendelian randomization is to use genetic variables as instrumental variables ... studies.
RESULTS: A variety of functional forms were found, including reverse J/J-shaped relationships for prostate cancer and related mortality, dementia risk, mental health, and certain lipids. However, most outcomes were only evaluated by a single study, and few studies provided information on the role of alcohol consumption pattern. CONCLUSIONS: More research employing enhanced causal inference methods is urgently required to accurately characterize alcohol-long-term health relationships. Those studies that have been conducted find a variety of linear and non-linear functional forms, with results tending to be discrepant even within specific health outcomes.
TRIAL REGISTRATION: PROSPERO registration number CRD42020185861.
Additional Info
-
Authors
Visontay R.; Sunderland M.; Slade T.; Wilson J.; Mewton L. -
Issue
BMC Med Res Methodol. 2022; 22: 16. Published online 2022 Jan 14. doi: 10.1186/s12874-021-01486-5 -
Published Date
14 january 2022
Related items
- Mediterranean diet: definitions, health effects and metabolic pathways – evidence and future directions
- Association of self-reported alcohol consumption compared with abstention with major adverse cardiovascular events, cancer, and mortality among United States veterans: a cohort study from the Million Veteran Program
- Beyond alcohol: reassessing wine in the context of the Mediterranean diet and drinking patterns
- Alcohol Marketing Exposure and Youth Drinking: A Systematic Review and Meta-Analysis
- Interpreting the Evidence on Wine Consumption and Health: A Narrative Review of the J-Shaped Association and Contemporary Alcohol Guidelines