Coronary Artery Calcium Progression Among the US and Japanese Men

Background The risk of coronary heart disease remains low in Japan, although distributions of several coronary risk factors have become comparable with those in the United States. We prospectively compared coronary atherosclerosis burden, measured with coronary artery calcium (CAC) progression, between men in the 2 countries. Methods In 2 population-based samples of 1712 US White, Black, Hispanic, Chinese men (baseline, 2000–2002) and 697 Japanese men in Japan (2006–2008) aged 45–74 years without clinical cardiovascular disease, we quantified CAC progression by serial computed tomography with medians of 3.4 and 5.2 years between scans, respectively. Results Among White, Black, Hispanic, Chinese, and Japanese men free of baseline CAC, CAC incidence was observed in 35.2%, 26.9%, 29.2%, 18.9%, and 29.2%, respectively. After adjustment for times between scans, demographics, behaviors, coronary risk factors, and their changes between scans, White men had significantly higher CAC incidence than Japanese men (re...