Common anti-cholesterol drugs show promise for reducing the risk of Alzheimer’s disease, a University of Southern California-led (USC) study of medicare data reveals.

The new study shows that, based on a sample of 399,979 medicare beneficiaries, men and women who took statins two years or more lowered their risk of Alzheimer’s disease in the period spanning from 2009 to 2013.

The incidence of Alzheimer’s disease was reduced for beneficiaries frequently prescribed statins (high users), compared to low users, USC and University of Arizona researchers found. Among women who were high users, the incidence rate was 15 per cent lower. Among men, the rate was 12 per cent lower.

Researchers noted that black men were the only group that did not show a statistically significant reduction in risk, likely due to sample size.

‘We may not need to wait for a cure to make a difference for patients currently at risk of the disease. Existing drugs, alone or in combination, may affect Alzheimer’s risk,’ said lead and corresponding author Julie Zissimopoulos, Associate Director of the USC Leonard D Schaeffer Centre for Health Policy and Economics and Assistant Professor at USC Price School of Public Policy.

Prior studies have shown a link between cholesterol and the hallmark of Alzheimer’s disease: the beta-amyloid plaques that interfere with memory and other brain functions.

‘We looked to statins as a candidate because they are widely-used and have resulted in the reduction of cholesterol,’ she said.