Boston Taking low dose aspirin does not protect older women against cognitive decline, finds a large study published on www.bmj.com today.

Identifying ways to prevent dementia is a public health priority. Evidence suggests that aspirin and other anti-inflammatory drugs may protect against dementia, but data from randomised studies to date have been inconclusive. So researchers in the US decided to test the effect of long term use of low dose aspirin on overall cognitive decline among a large sample of women.

Jae Hee Kang and colleagues at Brigham and Women’s Hospital in Boston, Massachusetts identified 6,377 women aged 65 years or more, who were taking part in the Women’s health study between 1998 and 2004.

The women were randomly divided into two groups. Over a period of nearly 10 years, the first group took low dose aspirin (100 mg on alternate days) and the second group took a placebo pill. Each woman had three cognitive assessments at two year intervals to measure general cognition, verbal memory, and category fluency.

At the initial assessment (after 5.6 years of treatment) cognitive performance in the aspirin group was similar to that of the placebo group. Average performance across all tests from the first to the final assessment (after 9.6 years of treatment) was also similar in the aspirin group compared with the placebo group. The risk of substantial decline was also comparable between the groups.

There was some suggestion that women in the aspirin group performed better in the category fluency test than women in the placebo group. However, the authors stress that this result should be interpreted with caution.

They conclude: “In this study, we observed no apparent benefit of low dose aspirin in slowing cognitive decline over four years. Other methods for preserving cognitive function in older people need to be investigated.”