The specificity of exercise electrocardiography in women grouped by estrogen status

We compared the specificity of exercise electrocardiography in 1880 men and 1818 women with women grouped by menopausal and estrogen replacement status. Specificity for ≥1 mm horizontal or downsloping ST-segment depression was determined using angiography in 781 patients and using two other nonangiography-based methods (a pretest probability-based method and a predictive accuracy-based method) in all patients. Using angiography, the specificities±SE were 84±2 for men, 79±3 for women, 81±5 for premenopausal women, 81±4 for postmenopausal women without estrogen replacement, and 77±5 for women on estrogen replacement. None of these were significantly different. For all patients, the respective specificities using the probability and predictive accuracy-based methods were 97±1 and 94±1 for men, 90±1 and 88±1 for women, 97±1 and 92±2 for premenopausal women, 92±4 and 88±3 for postmenopausal women without estrogen replacement, and 85±4 and 81±3 for women on estrogen replacement. (Men vs. all women groups except premenopausal women — P<0.05). Therefore, the premenopausal women had significantly greater specificity than women on estrogen replacement (P<0.001) and no difference in specificity with men. Women on estrogen replacement had a significantly lower specificity than postmenopausal women not on estrogen replacement (P<0.05). These results suggest that estrogen replacement therapy and not naturally occurring estrogen has a role in producing false positive exercise electrocardiograms in women.