NEW YORK (Reuters Health) - Results of a new study suggest that taking cholesterol-lowering statin drugs may decrease the risk of cognitive impairment and dementia in older adults.

In the study, people at high risk for dementia who took statins were half as likely to develop dementia as those who did not take statins.

"The bottom line is that if a person takes statins over a course of about five to seven years, it reduces the risk of dementia by half, and that's a really big change," Dr. Mary N. Haan, who was involved in the study, said in a written statement. She notes that the study did not look at statins as a treatment for existing dementia, only as a preventative.

Many studies have examined the potential benefits of statins on cognitive function in older adults, with inconsistent results. Haan and colleagues from the University of Michigan in Ann Arbor further examined these issues in a population-based study comprising 1,674 Mexican Americans at least 60 years old and free of cognitive impairment in 1998.

During the five years they were followed, 130 subjects developed dementia or cognitive impairment.

Among the 452 subjects who used statins during the study period, the risk of developing dementia or cognitive impairment was cut by half, Haan and colleagues found.