Statins may offer a dementia prevention advantage in people with no history of cognitive dysfunction. In a meta-analysis published in the October issue of Mayo Clinic Proceedings, researchers found that short-term data suggest statins do not adversely affect cognition and long-term data suggest some preventive benefit.

Researchers included 11 studies in their analysis that assessed the relationship between statin use and cognitive dysfunction. The studies were randomized controlled trials or high-quality prospective cohort studies. As outcomes, they used validated cognitive tests for short-term cognition and a new dementia diagnosis for long-term cognition.

Based on three studies with 296 exposures, Digit Symbol Substitution, a validated cognitive test, was the most common short-term outcome. There were no significant differences in the mean change between the statin and placebo groups from baseline to follow-up.

Three long-term studies did not find a link between statin use and new-onset dementia, but five found statins had some protective benefits. The researchers then performed a pooled analysis.

“In the long-term studies, results were consistent with a protective statin effect on dementia, with a 29 percent relative reduction and a 2 percent absolute risk reduction,” wrote the authors, led by Kristopher J. Swiger, MD, of Johns Hopkins University in Baltimore, Md.

Based on their eligibility criteria, several large trials were not part of the analysis, including PROSPER (Prospective Study of Pravastatin in the Elderly at Risk) and the Heart Protection Study. Both found that statin use protected against cardiovascular disease.

Despite these exclusions, the authors argued that their findings are encouraging.

“At present, patients and physicians can be reassured about concerns related to neurocognitive effects of statin therapy, and the evidence does not support a change to practice guidelines,” they wrote.