Seattle, WA - Taking statins for cardiovascular health does not seem to provide any defense against developing dementia, according to an observational study of more than 2700 community-dwelling older adults that appears in the July 2005 issue of the Archives of Neurology [1].

Lead study author Dr Thomas D Rea (University of Washington, Seattle) explained to heartwire that his group "did not find a protective association of statins against the risk of dementia, in contrast to several prior studies that have found a potential protective
effect. . . . It gives caution to statin's role in prevention of dementia and calls for more investigation."

Statins prevent cardiovascular risk in at-risk populations, and, based on previous work, the investigators hypothesized that these drugs were also associated with a lower risk of dementia. If this were proven true, it would have tremendous public-healthcare implications.

The research team used data from the Cardiovascular Health Cognition Study, a subset of the Cardiovascular Health Study. The 2798 participants were over age 65, living in the community, and free of dementia at baseline, as determined by MRI findings and Mini-Mental State Examination (MMSE) scores. The main outcomes were incident all-cause dementia and dementia solely due to Alzheimer's disease (AD). During the 15 030 person-years of follow-up, there were 480 cases of dementia: 245 solely AD, 151 AD and vascular dementia (VaD), 62 VaD, and 22 other types of dementia.

Compared with never-users, statin users showed no change in risk of dementia.

In addition, former use of statins was linked to an elevated risk of all-cause dementia, compared with never-users. "'I think that means that as people begin to develop symptoms of dementia, physicians and family are likely to ask, 'Why are we treating this person for cholesterol when really we should be trying to maintain their quality of life?' "

Several factors might explain why these findings differ from prior case-control studies that suggested a possible role for statins in reducing risk of dementia. This study—and two other recently published prospective studies that presented similar outcomes—used different methods from earlier investigations. Participants were, on average, 75 years old and had been taking statins for five years. Perhaps longer, earlier exposure would be needed.

"The main and only indication for statins is prevention of cardiovascular disease, and it's not approved for use in dementia prevention," Rea told heartwire. "These findings really shouldn't have great impact on current clinical practices, but they point out that there is conflicting information and we might want to gather more data to provide the highest level of evidence, in the form of a randomized trial."