Will Exercise ward off Dementia? - February 2016
Zaldy S. Tan, MD - January 14, 2016
The Framingham study was one of the first to show that regular exercise is recognised as having an inverse relationship with the incidence of stroke, peripheral vascular disease, and congestive heart failure. In contrast, the association between regular exercise and dementia is less clear.
Several studies have demonstrated that higher levels of physical activity lower the risk for cognitive decline and dementia. In the Nurses' Health Study, women with the highest levels of physical activity were 20% less likely than those with the lowest levels to show cognitive decline over a decade later. In another study, focusing on persons 65 years of age and older, participation in 45 minutes of aerobic exercise per week was associated with a decreased risk for dementia compared with those who were more sedentary. However, not all studies support this relationship longer-term. In the Bronx Aging Study, participation in leisure cognitive activities such as reading, playing board games, and playing a musical instrument were associated with a decreased risk for dementia, while physical activity alone (e.g. walking, bicycling, swimming) was not. Well-designed interventional studies using exercise to prevent dementia have yet to be published.
Exercise prescription alone to ward off forms of dementia may be premature, but the other known benefits of regular physical activity make it a sound and evidence-based recommendation to promote overall health. Furthermore, given that regular exercise has been shown to reduce the risk for stroke-a known risk factor for dementia-clinicians have a basis for encouraging regular physical activity in patients who are interested in promoting brain health. - Medscape Online