New study findings suggest that the cholesterol-lowering drugs know as “statins” do not appear to lower the risk of dementia or Alzheimer’s disease, except possibly in cases of early-onset Alzheimer’s disease.

This runs counter to recent reports indicating that these drugs do, in fact, reduce the risk of dementia and Alzheimer’s disease.

The authors of the current study, reported in the November 9th issue of the medical journal Neurology, believe the discrepancy may have to do with how the data were analyzed.

Dr. Gail Li, from the University of Washington in Seattle, and colleagues assessed the outcomes of 2,356 elderly subjects without dementia who were in a health maintenance organization. The subjects were enrolled in the study between 1994 and 1996 and were evaluated every two years until the end of 2002.

During follow-up, 312 subjects were diagnosed with all-cause dementia and 168 with probable Alzheimer’s disease.

As noted, statin use did not have a significant effect on the risk of dementia or Alzheimer’s disease. Moreover, there was no evidence that higher or lower doses of statin affected the development of dementia.

However, statin use was linked with a lower risk of “probable” Alzheimer’s disease in subjects younger than 80 years who also had a least one copy of APOE E4, a gene mutation associated with increased risk of Alzheimer’s disease. But this relationship was not strong.

“Our results argue against the general premise that statins used for prevention of coronary heart disease will result in prevention of dementia or Alzheimer’s disease, except perhaps in subgroups at high risk for early-onset Alzheimer’s disease or in persons starting statins at a younger age and taking them for longer periods of time,” Li’s team concludes.

SOURCE: Neurology, November 9, 2004.