Over the years, a small body of research has suggested that too-low cholesterol levels might be associated with changes in affect or behavior. Researchers from the University of Pennsylvania examined this issue in a double-blind, randomized trial involving older adults.
Eighty healthy volunteers (age, 65 or older; mean total cholesterol level, 215 mg/dL) received simvastatin (titrated to 20 mg/day) or placebo for 15 weeks. During the study period, depression scores (as indicated on the standardized CES-D scale) remained similar in the groups. However, on another scale (the Lawton scale), in which subjects recorded affective states in daily diary entries, a statistically significant decrease in positive affect (e.g., happiness, contentment, energy) emerged in the simvastatin group compared with the placebo group. At 90 days, 31% of simvastatin recipients and 10% of placebo recipients were judged to have clinically significant changes on the Lawton scale. The change in positive affect was statistically significant only among subjects whose final serum cholesterol was lower than 148 mg/dL (a level reached by half the simvastatin recipients but no placebo recipients).
These findings support the hypothesis that aggressive cholesterol lowering might result in subtle affective changes in older adults. It is unclear whether lowered cholesterol levels, by simvastatin specifically or due to a general statin class effect, were responsible for the findings. Because statin use is increasing in older populations, additional research in this area is needed.
Reference:
Morales K et al. Simvastatin causes changes in affective processes in elderly volunteers. J Am Geriatr Soc 2006 Jan; 54:70-6.