Impact of inflammation on the relationship among alcohol consumption, mortality, and cardiac events: the health, aging, and body composition study

BACKGROUND: Uncertainty remains about the overall survival benefit of alcohol consumption and the mechanisms underlying the cardioprotective effect of light to moderate alcohol intake. Recent evidence suggests an anti-inflammatory effect of light to moderate alcohol consumption. We investigated the relationship of alcohol intake with all-cause mortality and cardiac events and evaluated whether this relationship is mediated or modified by inflammatory markers. METHODS: The analysis included 2487 subjects, aged 70 to 79 years, without baseline coronary heart disease (CHD) or heart failure (HF), participating in the Health, Aging, and Body Composition study. All-cause mortality and incident cardiac events (CHD and HF) were detected during a mean follow-up of 5.6 years. Alcohol consumption and serum levels of interleukin-6 (IL-6) and C-reactive protein (CRP) were assessed at baseline. RESULTS: A total of 397 participants died, and 383 experienced an incident cardiac event. Compared with never or occasional drinkers, subjects drinking 1 to 7 drinks per week had lower age-, sex-, and race-adjusted incidences of death (27.4 vs 20.1 per 1000 person-years, respectively) and cardiac events (28.9 vs 20.8 per 1000 person-years). After adjustment for confounders, compared with never or occasional drinkers, light to moderate drinkers (1-7 drinks per week) showed a decreased risk of death (hazard ratio HR], 0.75; 95% confidence interval CI], 0.56-1.00) and cardiac events (HR, 0.72; CI, 0.54-0.97). Adjustment for potential mediators, and particularly inflammatory marker levels, did not affect the strength of this association. CONCLUSION: Light to moderate alcohol consumption was associated with significantly lower rates of cardiac events and longer survival, independent of its anti-inflammatory effect.