Background and purpose: Subclinical findings on MRI of the brain are associated with poorer cognitive and neurological function among older adults. We sought to determine how alcohol consumption is related to these findings.
Methods: As part of the Cardiovascular Health Study, 3660 adults aged 65 years and older underwent MRI of the brain from 1992 to 1994. We excluded 284 participants with a confirmed history of cerebrovascular disease. We assessed self-reported intake of beer, wine, and liquor at the annual clinic visit closest to the date of the MRI and grouped participants into 6 categories: abstainers, former drinkers, <1 drink weekly, 1 to <7 drinks weekly, 7 to <15 drinks weekly, and >/=15 drinks weekly. Neuroradiologists assessed white matter grade, infarcts, ventricular size, and sulcal size in a standardized and blinded manner. We used multivariate regression to control for sociodemographic and clinical characteristics.
Results: We found a U-shaped relationship between alcohol consumption and white matter abnormalities. Compared with abstainers, individuals consuming 1 to <7 drinks had an OR of 0.68, and those consuming >/=15 drinks weekly had an OR of 0.95 (p for quadratic term=0.01). Heavier alcohol consumption was associated with a lower prevalence of infarcts (OR for >/=15 drinks weekly relative to abstainers 0.59; P for trend=0.004), but larger ventricular size (OR for >/=15 drinks weekly relative to abstainers 1.32; P for trend=0.006) and sulcal size (OR for >/=15 drinks weekly relative to abstainers 1.53; P for trend=0.007).
Conclusions: Moderate alcohol consumption is associated with a lower prevalence of white matter abnormalities and infarcts, thought to be of vascular origin, but with a dose-dependent higher prevalence of brain atrophy on MRI among older adults. The extent to which these competing associations influence overall brain function will require further study.