Higher exercise capacity, but not omega-3 fatty acid consumption, predicts lower coronary artery calcium scores in women and men with coronary artery disease

Abstract

Background and aims: Higher coronary artery calcium (CAC) scores are associated with increased cardiovascular (CVD) events and mortality. Exercise capacity is predictive of CVD events. Our aim was to examine the relationship between exercise capacity and CAC in women and men.

Methods: CAC was measured in 203 men and 38 women with clinical coronary artery disease using multidetector coronary tomography. They were randomized to 3.36 g eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) daily or none for 30 months. Maximal exercise treadmill testing was performed at baseline with calculation of metabolic equivalents of task (METs) achieved as a measure of exercise capacity.

Results: Despite similar ages at baseline (64.0 ± 6.7 vs 62.7 ± 7.8 years, respectively, p = 0.225), women had lower CAC scores compared to men: 106.7 Agatston units [AU] vs 535.3, respectively, p < 0.001, and at every age (p < 0.001). Female CAC scores did not equal those of men until women were 20 years older. Higher levels of METs were associated with lower CAC scores in both women and men. After multivariate adjustment, METs was the most important predictor of CAC score in women at baseline and 30 months (p = 0.001 and 0.029, respectively) whereas only age predicted in men (p = 0.019 and 0.004, respectively). Annual CAC progression was significantly greater in men compared to women (94.8 AU/year vs 38.0, respectively, p = 0.014). No difference was observed in CAC progression in the EPA + DHA group compared to control in either men or women.

Conclusions: The association of higher METs with lower CAC scores in both women and men supports recommending exercise to maximize cardiorespiratory fitness as this may minimize CAC scores and thus, potentially decrease risk for CVD events. This may be especially important for women since METs independently predicted baseline and 30 month CAC in women.

Trial registration: ClinicalTrials.gov NCT01624727.

Keywords: Coronary artery calcium score; Docosahexaenoic acid; Eicosapentaenoic acid; METs; Omega-3 fatty acids; Sex differences; Women.