Statin reduces dementia risk.

A popular anticholesterol drug cuts older adults' chances of developing dementia by more than half, according to a new review of 4.5 million medical records.

Earlier research offered a mixed picture of cholesterol-reducing statins and their ability to prevent Alzheimer's disease and other dementias. Researchers at Boston University and the Veterans Administration (VA) in Washington, D.C., suspected that the confusion may have arisen from the failure of those studies to sort out the effects of various statin medications.

Researchers from the two institutions reviewed the records of patients treated at VA hospitals from 2002 to 2005.

Of three statin drugs on the market today, simvastatin (Zocor) offered the greatest protection against dementia. Patients 65 and older who took it for at least 7 months during the 3-year study period were 54 percent less likely to develop clinical dementia as were patients taking nonstatin heart medicines. Simvastatin also cut the risk of a Parkinson's disease diagnosis by 49 percent.

Atorvastatin (Lipitor) reduced dementia risk by 9 percent, while lovastatin (Mevacor) offered no such advantage.

The huge study included 700,000 patients who took simvastatin and 50,000 who took atorvastatin. Patients averaged 75 years of age. The team published its results online July 19 in BMC Medicine.--B.V.