Higher midlife fitness linked to lower all-cause dementia risk

(HealthDay)—Individuals with higher midlife cardiorespiratory fitness levels are significantly less likely to develop all-cause dementia later in life, according to research published in the Feb. 5 issue of the Annals of Internal Medicine.

Laura F. DeFina, M.D., of The Cooper Institute in Dallas, and colleagues conducted a prospective, observational cohort study involving 19,458 community-dwelling, nonelderly adults who had taken a baseline fitness test between 1971 and 2009. The authors sought to examine the correlation between midlife cardiorespiratory fitness levels and dementia later in life.

During 125,700 person-years of Medicare follow-up, the researchers identified 1,659 cases of incident all-cause dementia. Participants in the highest fitness level quintile had a significantly lower risk of all-cause dementia compared with those in the lowest fitness quintile, after multivariable adjustment (hazard ratio, 0.64). Higher fitness levels were also associated with a lower risk of all-cause dementia with and without previous stroke (hazard ratio, 0.74 for both).

"In this cohort of generally healthy, community-dwelling persons having preventive health evaluations, we saw an association between midlife fitness levels measured with treadmill testing and lower risk for dementia in later life independent of other cardiovascular risk factors," the authors write. "The association seemed to be present with or without intervening cerebrovascular events, suggesting that the effect of midlife fitness levels on the prevention of dementia in later life may have both vascular and nonvascular mechanisms."