The Longitudinal Effects of Moderate Alcohol Use on Mood and Cognition in Late Life Depression

Introduction Alcohol use disorder interferes with antidepressant treatment in older adults with major depression (LLD) and is associated with suicidal ideation. Less is known about the effects of moderate alcohol use in LLD on mood and cognitive outcomes over time. Much of the evidence on alcohol use and cognition and mood stems from epidemiological research and not clinical studies of depressed older adults. The purported benefits of moderate alcohol use on older adults’ cognitive functioning have often been reported. Yet, not all studies report a positive association between moderate alcohol use and cognitive functioning, and there is also other evidence to suggest moderate alcohol use is correlated with markers of poorer brain health in older adults (e.g., atrophy). In respect to mood, epidemiological research suggests little to no association between moderate alcohol use and depression in older adults or even an inverse association with increased social interactions as a mediator. Given the times at conflicting evidence and the lack of longitudinal studies in well-defined clinical samples, we hypothesized that depressed older adults who were moderate drinkers would experience greater cognitive decline compared to depressed non-drinkers. We also hypothesized that moderate alcohol use would have a detrimental effect on depression illness course in older adults with LLD. Methods This study used data from Neurocognitive Outcomes of Depression in the Elderly (NCODE) study. NCODE participants underwent annual neuropsychological evaluations with the Consortium to Establish a Registry of Alzheimer's Disease (CERAD) cognitive battery as well as other tests of executive functioning and processing speed (e.g., Trail Making Test). Participants also underwent annual depression severity ratings with a geriatric psychiatrist using the Montgomery Asberg Depression Rating Scale (MADRS). We used patients self-reported alcohol use at the time of study entry and characterized them as either abstainers (n=81) and moderate drinkers (n=30). We were also able to define a small sample of risky drinkers (n=10) and included this group for exploratory reasons. Alcohol use was based upon NIAAA guidelines for older adult alcohol consumption. Risky alcohol use exceeded NIAAA alcohol consumption guidelines for older adults (meaning >=3 drinks per day or >=8 drinks per week) and moderate alcohol use was defined as Results In terms of cognition, we found that the total CERAD score of moderate and heavy drinkers significantly declined compared to no alcohol use patients (e.g.,moderate alcohol use x time interaction term estimate = -.00410, DF = 898, t = -5.02, p Conclusions Moderate alcohol consumption appears to have a beneficial impact on depression severity and a detrimental impact on cognitive functioning in LLD patients followed for upwards of five years. Larger samples are needed to confirm the findings in this small and exploratory study.