Heavy Drinking Associated with Greater Risk for Myocardial Infarction in a Study that Measured Alcohol More than Once

Most studies of the association between alcohol use and myocardial infarction (MI) use a single baseline measure of consumption and assume it doesn’t change over subsequent years. Suspecting that such studies might yield biased results, researchers in Finland measured the association between alcohol use and MI among 1030 men in a prospective heart disease risk-factor cohort study, including 3 assessments of consumption (at study entry, 2–9 years later, and 5–10 years after that). Average weekly alcohol use over a year was categorized into 4 groups: <12 g,* 12–83 g, 84–167 g, and ≥168 g. Adjusted analyses controlled for age, working status, diabetes, smoking, cardiovascular disease, body mass index, HDL cholesterol, systolic blood pressure, insulin, and fibrinogen. Incidents of MI were recorded over the latter 14-year period of follow-up.

• In a model examining 1 assessment of alcohol consumption, relative risks (RRs) for MI were 1.10, 1.05, and 0.98 for subjects consuming <12 g, 84–167 g, and ≥168 g alcohol per week, respectively, compared with 12–83 g per week (not statistically significant).

• In an adjusted model that also included all 3 measurements of alcohol consumption, RRs were 1.27, 1.27, and 1.71 for subjects consuming <12 g, 84–167 g, and ≥168 g alcohol per week, respectively, with a significant increased risk among only the heaviest drinkers.

Comments:

Of note, alcohol consumption did not reduce the risk for MI in any models. However, these results indicate that, when assessing the relationship between MI and alcohol use, the association may differ when alcohol use is assessed and included in statistical models over time and when the analysis is adjusted for various confounders. Observational studies of alcohol use and health outcomes should not rely on 1 short-term measurement of consumption. Clinicians and the public should use caution when interpreting the results of such studies, which currently comprise the bulk of the evidence supporting associations between drinking, cardiovascular disease, and death.

Nicolas Bertholet, MD, MSc

Reference:

Ilomäki J, Hajat A, Kauhanen J, et al. Relationship between alcohol consumption and myocardial infarction among ageing men using a marginal structural model. Eur J Publ Health. March 11, 2011 (E-pub ahead of print), doi: 10.1093/eurpub/ckr013.