Regular Exercise Lowers Dementia risk

Healthnotes Newswire (April 6, 2006)-Older people who exercise regularly have a lower risk of developing dementia than those who don't, according to the Annals of Internal Medicine (2006;144:73-81).

Dementia, one of the most common debilitating conditions of the elderly, is characterized by progressive memory loss and problems with normal thought (cognitive) function. Millions of people in the United States have Alzheimer's disease and other forms of dementia, and that number is increasing as the population ages. The risk of dementia is partly determined by genetics, but some lifestyle factors also play a role. In particular, studies have found that antioxidants and omega-3 fatty acids in the diet might protect against cognitive decline and dementia. Exercise has also been found to reduce the risk of Alzheimer's disease and other forms of dementia.

The 1,740 people who participated in the current study were at least 65 years old and were living in the community (not in nursing homes). Cognitive testing was done prior to enrollment in the study, and only people without evidence of impaired cognitive function or dementia were selected to participate. Follow-up testing was done after two, four, and six years to monitor changes in cognitive function. Physical exercise was assessed at the beginning of the study using a questionnaire. Those who had exercised for 15 minutes or more three or more times per week for the previous year were identified as regular exercisers. Other lifestyle factors, health history, and physical function were also evaluated at the beginning of the study.

Regular exercisers were found to be 32% less likely to develop dementia during the study than people who did not exercise regularly. A significant relationship between poor physical functioning at the beginning of the study and increased risk of developing dementia was also noted. The degree of protection conferred by exercise was greatest among those with poor physical functioning - regular exercise reduced their risk by 42%.

These results add to the evidence that exercise has a beneficial effect on dementia risk. The link between poor physical functioning and increased benefits from exercise was an important finding from this study, suggesting that it is never too late to begin an exercise program. More research is needed to confirm this link; in the meantime, healthcare providers can add protection against dementia to the list of reasons to recommend regular exercise to all seniors in their care, including- and perhaps most importantly- those with poor physical ability.