Abstract
BACKGROUND: To compare the results of myocardial perfusion imaging (MPI) of asymptomatic postmenopausal women and age-matched men and to investigate the effect of diabetes mellitus (DM) on gender differences and the risk estimation of coronary heart disease (CHD). METHODS: Sixty-seven postmenopausal women and 27 men low in Framingham Global Risk Score (FGRS) were recruited from year 2008 to 2009 in northern Taiwan. Each subject underwent blood tests, a cardiopulmonary exercise test, an electrocardiograph (ECG), and MPI. RESULTS: Women had similar percentages of predicted oxygen consumption and ECG changes at peak exercise, but lower oxygen pulse and rate-pressure product. They also had significantly higher summed stress score (SSS), summed rest score (SRS), and summed difference score (SDS) than men, despite showing much lower scores for the FGRS than men. Women with DM had a lower 10-year risk of CHD assessed by the United Kingdom Prospective Diabetes Study (UKPDS) risk engine, but significantly higher SSS and SDS than men. In the subjects with abnormal MPI, the extent of ischemia was small to moderate in men, whereas in 50% of the women, the extent of ischemia was large. CONCLUSION: The results of this preliminary study suggest that asymptomatic postmenopausal women had more abnormalities in MPI and those with DM had a higher SSS and SDS than age-matched men. The risk of CAD may still be underestimated by the UKPDS.