Alcohol consumption and frontal lobe shrinkage: Study of 1432 non-alcoholic subjects

Objectives - To evaluate the influences of chronic alcohol consumption on brain volume among social drinkers, as it is well known that alcohol misusers have a high risk of brain shrinkage. Methods - Frontal lobe volumes on MRI were compared with the current alcohol habits of consecutive 1432 non-alcoholic subjects. Results - After adjusting for other variables, age was found to be the most powerful promoting factor for the shrinkage with a odds ratio of 2.8 (95% confidence interval (95% CI) 1.23-3.06) for each 10 years of age. Regarding alcohol habit, 667 of the subjects were abstainers, and 157, 362, and 246 of the subjects were light (average 88.2 g ethanol/week), moderate (181.2 g/week), and heavy (418.1 g/week) drinkers, respectively. Moderate alcohol consumption did not increase the incidence of frontal lobe shrinkage (odds ratio 0.98; 95% CI 0.73-1.33), whereas heavy drinkers were at a higher risk compared with abstainers (1.80; 1.32-2.46). The contributory rate of alcohol consumption for frontal lobe shrinkage was 11.3%. Conclusion - The brain tends to shrink physiologically with age. Heavy alcohol consumption seems to exaggerate this shrinkage in social drinkers. Moderate alcohol consumption does not seem to affect brain volume.