Objective:
We investigated three potential errors embedded in epidemiological evidence that could mask the health effects of alcohol, i.e., by using abstainers as reference group, combining alcohol from all drink types, and including protective relationships with ischemic heart disease when assessing overall cardiovascular (CV) risk.
Design and method:
The UK Biobank cohort consists of over 500,000 participants that attended one of 22 assessment centers across the United Kingdom. We calculated baseline alcohol intake as grams per week and followed CV outcomes for a median 6.9 years.
Results:
Never drinkers were at higher risk for all CV events (P < 0.0001), ischemic heart disease (P < 0.0001) and cerebrovascular disease (P < 0.0001). Alcohol from all drink types combined and beer/cider and spirits combined predicted CV events (both P < 0.024) and cerebrovascular events (both P < 0.011). Associations were stronger for beer/cider and spirits for both CV events (hazard ratio, 1.24 vs 1.08, P < 0.0001) and cerebrovascular events (hazard ratio, 1.30 vs 1.15, P < 0.0001). No relationships existed with ischemic heart disease (both P > 0.11). Wine was protective for CV events (P = 0.008) and ischemic heart disease (P < 0.0001), but not cerebrovascular events (P = 0.34). Excluding ischemic heart disease events resulted in the nullification of CV protection from wine (P = 0.95), while alcohol captured from beer/cider and spirits remained predictive (P < 0.0001).
Conclusions:
The use of abstainers as reference group, combining of all drink types including wine when capturing alcohol intake, and embedding the protective relationship between ischemic heart disease and wine in CV risk prediction, masks the health risks associated with alcohol intake and falsely portrays alcohol as protective.
