Sex differences in the association between cardiovascular risk factors and coronary artery calcification progression among individuals without coronary artery calcium.

BACKGROUND: Cardiovascular risk factors are determinants of coronary artery calcium (CAC) progression. However, whether the effect of cardiovascular risk factors on CAC progression among participants with CAC = 0 differs by sex remains unclear. METHOD: This study included 1815 participants 33-45 years of age from the Coronary Artery Risk Development in Young Adults study at baseline who had CAC measured both at baseline and five years later. CAC was measured using computed tomography. Risk factor measurements included body mass index (BMI), waist circumference, total cholesterol, triglycerides, glucose, systolic blood pressure (BP), low-density lipoprotein cholesterol, and smoking status. RESULTS: CAC progression was significantly higher among men than women (2.25 (8.68) vs. 0.89 (6.7), P < 0.0001). In the restricted cubic spline models, the associations between systolic BP and CAC progression in women followed a nonlinear relationship. The slope for the regression of systolic BP on CAC progression in women was relatively flat until around 125 mmHg of systolic BP and then started to increase rapidly afterwards, with a β of 0.16. BMI was associated with CAC progression only in men. Similar associations were observed when replacing BMI with waist circumference. There were no sex differences in the associations between CAC progression and smoking. CONCLUSION: Systolic BP in women and BMI (and/or waist circumference) in men may have different contributions to CAC progression between the sexes among participants with CAC = 0. Our study provides evidence that understanding sex differences in cardiovascular risk factors is essential for implementing targeted interventions to prevent CAC progression.