Abstract 107: A Field Synopsis of Sex in Clinical Prediction Models for Cardiovascular Disease

Abstract

Introduction: Incorporating sex in Clinical Prediction Models (CPMs) may support sex-specific clinical decision making. Risk scores commonly used in CVD prevention, such as the Pooled Cohort Equation and the Framingham risk score for 10 year CVD risk, present sex-specific algorithms, yet to date, there has been no systematic summary of the role of sex across CPMs. To better understand the potential influence these models might have on sex-specific care, we conducted a field synopsis of the role of sex in CPMs for CVD. Methods: We identified CPMs in the Tufts PACE CPM Database, a systematic review of CVD CPMs published from 1/1990-5/2012. We report the proportion of models including the effect of sex on CVD incidence or prognosis, summarize the directionality of sex effects (harm or protection associated with female sex), and explore factors influencing the inclusion of sex. Results: Out of 592 CPMs with CVD as either an index condition or outcome, 173 (34%) contained a coefficient for sex and 27 (5%) presented sex-stratified models. Sex was over 2.5 times more likely to be included in models predicting CVD incidence in a general population sample versus models predicting prognostic outcomes among patients with known CVD (79% (54/68) vs. 29% (146/498), p<0.0001). Among the 366 CVD-related models that did not include sex as a covariate or stratification variable, 71% reported that sex had been considered as a candidate for inclusion based on clinical or statistical criteria. Being a woman was associated with lower risk of death in 8 of 8 models predicting mortality among patients with heart failure that included sex as a covariate (see figure), yet a higher risk of death among women undergoing revascularization procedures in 10 of 12 CPMs. In multivariable analysis, the number of outcome events (OR=2.6, 95% CI 1.6-4.4, p=0.0002) and a cohort defined as a population sample at risk for developing CVD (OR=6.2, 95% CI 2.7-14.1, p<0.0001) were significantly associated with inclusion of sex in CPMs. Conclusions: Sex is included in about one third of published CPMs, but more frequently in models predicting incidence of CVD. The importance of sex-specific care may be especially well established for primary prevention. The rapidly growing literature on CPMs may yield important insights to guide sex-specific CVD prevention and treatment.