Physical activity and subclinical MRI cerebral infarcts: the ARIC Study.

BACKGROUND: We hypothesized that physical activity (PA), which is often associated with reduced risk of ischemic stroke, may also be associated with reduced risk of subclinical cerebral infarcts.

OBJECTIVES: We studied the cross-sectional association between PA and subclinical cerebral infarcts among African-Americans in the Atherosclerosis Risk in Communities (ARIC) Study.

METHODS: PA self-reported at baseline and images from cerebral MRI examination obtained 6 years later were evaluated for presence and location of subclinical infarcts > or = 3 mm in size. After exclusions, 944 participants were eligible for study.

RESULTS: The results suggested an inverse relationship between odds of having a subclinical cerebral infarct and level of PA on several measures, although the multivariable adjusted odds ratios (OR) were statistically significant only for the sport score. A 1-unit increase in the sport score, indicating more leisure PA, was associated with an adjusted OR for having a subclinical cerebral infarct of 0.62 (0.44-0.87), with a statistically significant monotonic trend across quartiles of the score (P = 0.01). There was no association of work scores with subclinical infarcts.

CONCLUSIONS: In African-Americans, sport PA was inversely related to subclinical MRI-detected cerebral infarcts assessed six years later.