GENDER DIFFERENCES IN REFERRAL TRENDS AND CLINICAL CHARACTERISTICS IN EVALUATION OF STABLE CORONARY ARTERY DISEASE (CAD) BY MYOCARDIAL SCINTIGRAPHY:A 20-YEAR ANALYSIS FROM A TERTIARY REFERRAL CENTER

Background There are gender differences in management of stable CAD, with evidence of delayed diagnosis in women. Differences in referral patterns and clinical risk of patients can impact outcomes. We compared differences in baseline risk and use of myocardial scintigraphy among male and female patients with suspected CAD in a tertiary center in Italy, over 20 years. Methods This is a cross-sectional observational study of 20,953 patients (31% women, mean age 66.8 y) who were evaluated across 5 yearly intervals from 2000 to 2020. Temporal trends in risk factors and test results were compared between men and women. Results Men were more likely to be referred, however there was a steady increase in number of women referred for evaluation. Among women, there was a significant increase in prevalence of hypertension, but no change in smoking or diabetes. Over time, women were noted to have significant decrease in presence of ischemic myocardium at risk, identified by semi-quantitative scores including SRS, SSS, SDS at rest and increase in Ejection Fraction, compared to men. (p<0.05) Conclusion There are gender differences in proportions and clinical risk of patients referred for stress testing. Trends suggest a substantial change in risk of inducible myocardial ischemia, likely related to better sensitivity of nuclear cameras vs differential risk assessment in women. Our findings are relevant to understanding gender differences in risk stratification and diagnostic accuracy in CAD, and its effect on outcomes.