Sex-based analysis of NSTEMI processes of care and outcomes by hospital: a nationwide cohort study

BACKGROUND: Contemporary studies demonstrate that non-ST-segment elevation myocardial infarction (NSTEMI) processes of care vary according to sex. Little is known regarding variation in practice between geographical areas and centres. METHODS: We identified 305 014 NSTEMI admissions in the United Kingdom (UK) Myocardial Ischaemia National Audit Project (MINAP), 2010-17, including female sex (110 209). Hierarchical, multivariate logistic regression models were fitted, assessing for differences in primary outcomes according to sex. Risk-standardized mortality rates (RSMR) were calculated for individual hospitals to illustrate the correlation with variables of interest. 'Heat maps' were plotted to show regional and sex-based variation in the opportunity-based quality indicator score (surrogate for optimal processes of care). RESULTS: Women presented older (77 years vs. 69 years, P < 0.001) and were more often Caucasian (93% vs. 91%, P < 0.001). Women were less frequently managed with an invasive coronary angiogram (58% vs. 75%, P < 0.001) or percutaneous coronary intervention (35% vs. 49%, P < 0.001). In our hospital-clustered analysis, we show a positive correlation between the RSMR and the increasing proportion of women treated for NSTEMI (R2 = 0.17, P < 0.001). There was a clear negative correlation between the proportion of women who had an optimum OBQI score during their admission and RSMR (R2 = 0.22, P < 0.001), with a weaker correlation in men (R2 = 0.08, P < 0.001). Heat maps according to the Clinical Commissioning Group (CCG) demonstrate significant regional variation in the OBQI score, with women receiving poorer quality care throughout the UK. CONCLUSION: There was a significant variation in the management of patients with NSTEMI according to sex, with widespread geographical variation. Structural changes are required to enable improved care for women.