Systematic Review and Meta-analyses Investigating Whether Risk Stratification Explains Lower Rates of Coronary Angiography Among Women With Non–ST-Segment Elevation Acute Coronary Syndrome

BACKGROUND: Guidelines recommend that all non-ST-segment elevation acute coronary syndrome (NSTEACS) patients with high-risk features receive a coronary angiogram. We hypothesised that the widely reported gender disparity in the use of angiography might be the result of women more frequently being stratified into the lower-risk category. OBJECTIVES: The aim of the study was to review studies reporting risk stratification of NSTEACS patients by gender, compare risk profiles, and assess impact on use of coronary angiography. METHODS: PubMed, Scopus, and EMBASE databases were searched on June 17, 2014, using MeSH terms/subheadings and/or key words with no further limits. The search revealed 1230 articles, of which 25 met our objective. RESULTS: Among the 28 risk-stratified populations described in the 25 articles, women were more likely to be stratified as high-risk in 13 studies; men were more likely to be stratified as high-risk in 3 studies. After meta-analyses, women had a 23% higher odds of being stratified as high-risk than did men (P = .001). Lower-risk patients were more likely to receive an angiogram in 15 study populations. CONCLUSIONS: Contrary to our hypothesis, this review showed that women with NSTEACS are more likely than men to be considered high-risk when stratified using a range of risk assessment methods. Lower rates of angiography in women form part of a broader treatment-risk paradox, which may involve gender bias in the selection of patients for invasive therapy.