Physical Activity, Vitamin D, and Incident Atherosclerotic Cardiovascular Disease in Whites and Blacks: The ARIC Study.

CONTEXT

Physical activity (PA) is associated with 25-hydroxyvitamin D [25(OH)D] levels. Both are associated with atherosclerotic cardiovascular disease (ASCVD), but their joint association with ASCVD risk is unknown.

OBJECTIVE

To examine the relationship between PA and 25(OH)D, and assess effect modification of 25(OH)D and PA with ASCVD.

DESIGN

Cross-sectional and prospective study.

SETTING

Community-dwelling cohort.

PARTICIPANTS

A total of 10,342 participants free of ASCVD, with moderate- to vigorous-intensity PA assessed (1987 to 1989) and categorized per American Heart Association (AHA) guidelines (recommended, intermediate, or poor).

MAIN OUTCOME MEASURES

Serum 25(OH)D levels (1990 to 1992) and ASCVD events (i.e., incident myocardial infarction, fatal coronary disease, or stroke) through 2013.

RESULTS

Participants had mean age of 54 years, and were 57% women, 21% black, 30% 25(OH)D deficient [<20 ng/mL (<50 nmol/L)], and <40% meeting AHA-recommended PA. PA was linearly associated with 25(OH)D levels in whites. Whites meeting recommended PA were 37% less likely to have 25(OH)D deficiency [relative risk, 0.63 (95% confidence interval [CI], 0.56, 0.71)]; there was no significant association in blacks. Over 19.3 years of follow-up, 1800 incident ASCVD events occurred. Recommended PA was associated with reduced ASCVD risk [hazard ratio [HR], 0.78 (95% CI, 0.65, 0.93) and 0.76 (95% CI, 0.62, 0.93)] among participants with intermediate [20 to <30 ng/mL (50 to <75 nmol/L)] and optimal [≥30 ng/mL (≥75 nmol/L)] 25(OH)D, respectively, but not among those with deficient 25(OH)D (P for interaction = 0.04).

CONCLUSION

PA is linearly associated with higher 25(OH)D levels in whites. PA and 25(OH)D may have synergistic beneficial effects on ASCVD risk.