Collections > Electronic Theses and Dissertations > Association of Mid-Life Alcohol Consumption with Stroke and Cognitive Decline in the Atherosclerosis Risk in Communities Study

One in three adults will experience stroke or develop dementia in their lifetime, underscoring the need to identify modifiable factors to delay or prevent disease. Alcohol, a common exposure in most populations, may confer cardiovascular benefits at light-to-moderate doses. Its association with stroke and cognitive function is uncertain. This dissertation aims to estimate the associations between mid-life alcohol consumption and incident stroke and rate of cognitive decline using data from the Atherosclerosis Risk in Communities Study, a biracial population-based cohort of 15,792 adults aged 45-64 at baseline with >20 years of follow-up. Alcohol consumption was self-reported as usual drinks per week; categorized as never, former, light (≤3), moderate (4-17), and heavier (≥18). One-third of participants were light drinkers, roughly one-fifth each were moderate, never and former drinkers and only 4% reported heavier consumption. Suspected strokes were obtained through self-report and hospital surveillance, validated using medical records, and adjudicated by physician experts. Light and moderate consumption were not strongly associated with ischemic stroke (HR=0.98, 95% CI 0.79-1.21; 1.06, 0.84-1.34) while heavier drinking was associated with a 31% increased rate relative to abstention in Cox proportional-hazard regression. Specification of intake with quadratic splines did not support a J-shaped relationship with stroke; we noted a roughly linear relative increase across intake. Moderate, but not light, consumption increased hemorrhage rates. Cognitive status was assessed at visits 2, 4, and 5 using three validated tests. Linear regression with generalized estimating equations estimated the difference in 20-year decline by alcohol intake. We used multiple imputation with chained equations to address informative attrition in sensitivity analysis. Global 20-year cognitive change did not differ between light drinkers and abstainers (0.019 z-score units; 95% CI -0.032, 0.070) and was somewhat faster for heavier drinkers (-0.041; -0.0152, 0.070). No consistent pattern in 20-year change was observed across tests, but effects were somewhat larger on tests of verbal fluency and executive function. Light-to-moderate consumption at mid-life was not associated with reduced stroke risk or slower cognitive decline compared with abstention over 20 years of follow-up in the ARIC study. Heavier consumption tended to increase the risk for both outcomes.