Is the incidence of dementia declining?
We really want this to be true, because it would mean a lot less suffering for our parents’ generation and in our own. It’s personal and as we age the threat of dementia feels closer and closer. Unfortunately, when we hear news about the incidence of dementia declining we need to remind ourselves that researchers are just beginning to examine this issue — right now we don’t really know.
In a study published in the May 8, 2012 issue of Neurology (abstract), researchers explained how they examined two cohorts of aging seniors in the Rotterdam Study. Beginning in 1990 researchers enrolled 10,994 men and women aged 55 and over and began following them up every two to three years, “aiming to investigate the prevalence and incidence of and risk factors for chronic diseases in the elderly.”
The researchers looked at two smaller groups of elderly participants, one group 1990 and a second similar group in 2000, and everyone in these smaller cohorts was free of dementia when they were initially examined.
The data, including information from brain scans, indicate that the brains in the second cohort were healthier (less atrophy) and that the incidence of dementia noticeably declined. The decline, however, was not large enough to be statistically significant (the difference between the two groups could have occurred by chance). However, researchers (and the journal editors) felt that the decline was so close to being significant that the findings should be published and that close attention should be paid, given the greater attention to the cardiovascular risk factors that contribute to dementia in the rapidly growing older population.
The fight against dementia continues.
- Obama administration presents national plan to fight Alzheimer’s disease – Department of Health and Human Service
- Aging and the Incidence of Dementia – Linked commentary/editorial in Neurology – not available to the public so check a medical library.
- Are Fewer People Developing Dementia? – Medscape article
- U.S. launches National Strategy to Combat Alzheimer’s Disease – PBS News Hour, May 15, 2012