Submitted to: Neuroepidemiology
Publication Type: Abstract only
Publication Acceptance Date: 9/29/2012
Publication Date: 10/30/2012
Citation: Morris, M.S., Wang, H., Jacques, P.F. 2012. Interaction between statin use and saturated fat intake in relation to cognitive test performance. Neuroepidemiology. 39:177-283. Interpretive Summary:
Technical Abstract: Strokes, microvascular disease, and Alzheimer’s disease adversely affect cognitive function in older people. High circulating cholesterol levels and amyloid-beta peptide deposition contribute to these conditions. Statins lower serum cholesterol by interfering with cholesterol biosynthesis, and they may also inhibit amyloid-beta production. Consequently, it is reasonable to hypothesize that statins would help prevent age-related cognitive impairment. However, study results have been mixed, and the US Food and Drug Administration warns of memory loss and confusion as possible consequences of statin use. The circumstances under which statin use might enhance or impair cognitive function deserve attention. Statin users are advised to consume a diet low in saturated fat to obtain maximum benefits. We were interested in potential effect modification by such a diet on the association between statin use and cognitive function. Participants aged > / = 60 years in the US National Health and Nutrition Examination Survey (1999–2002) were administered the Digit-Symbol Substitution Test (DSST) of information processing speed. Dietary data were collected via 24-hour recall; blood was drawn for the determination of many nutritional and health-status indicators, and information on lifestyle factors and chronic disease history was collected via questionnaire. Multiple linear regression analysis was used to assess the effect of meeting (versus not meeting) the 2010 Dietary Guidelines for Americans recommendation for saturated fat intake on the association between statin use and DSST performance among 2206 subjects who did not report a history of stroke. After controlling for demographic, nutritional, and lifestyle factors, the mean DSST score for statin users whose saturated fat intakes comprised at least 10% of their energy intakes was lower than that of non-users who also had high saturated fat intakes (Beta = -2.65, P = 0.035). On the other hand, among subjects who met the current recommendation for saturated fat intake of < 10% of energy, statin users had higher DSST scores than non-users of statins (Beta = 3.20, P = 0.004, P-interaction = 0.002). Whether statin use enhances or impairs cognitive function may depend on saturated fat intake.