Effects of atorvastatin on higher functions

Objective: This study was undertaken to assess the effects of atorvastatin on cognition and higher mental functions. Methods: In this before and after comparison study with controls, group one included 55 subjects aged >= N40 years requiring statins for cardiovascular indications who were started on atorvastatin (10 mg/day). Group two assigned to receive placebo were men and women chosen from the same geographical area and matched for age, sex, education and presence of hypertension and diabetes mellitus. Assessment was done with the Mini-Mental State Examination, Digit Span, Picture Test (average and delayed), Trail Making Test, Controlled Oral Word Association Test, Digit Symbol Substitution Test and Auditory Vigilance and Digit Vigilance Test at baseline and after 6 months. Changes between baseline and 6 months in the above parameters of mental function were compared using suitable statistical tests in the atorvastatin and placebo groups. To limit experiment-wise error, performance scores were grouped into five cognitive domains, which were labeled as attention, psychomotor speed, mental flexibility, working memory and memory retrieval. Summary effect sizes were estimated as z-scores. Results: Both subjects on atorvastatin and placebo showed improvement in the majority of scales consistent with a learning effect on test performance. However, subjects treated with atorvastatin scored significantly over the placebo group in all domains, i.e. tests of attention [z-score=0.54, 95% confidence interval (CI): 0.38-0.64, p=0.001], psychomotor speed (z-score=0.28, 95% CI: O.09-0.47, p < 0.001), mental flexibility (z-score=0.27, 95% CI: 0.22-0.32, p=0.01), working memory (z-score=1.22, 95% CI: 0.93-1.50, p < 0.001) and memory retrieval (z-score=0.59, 95% CI: 0.36-0.82, p < 0.05). Conclusion: The present study concludes that there are significant beneficial effects of atorvastatin in a dose of 10 mg/day for a period of 6 months on higher functions as measured by the above standard neurocognitive tests.