Gender differences in use of invasive diagnostic and therapeutic procedures for acute ischaemic heart disease in Chinese adults

OBJECTIVE: To investigate gender differences in the use of diagnostic and therapeutic procedures for acute ischaemic heart disease (IHD) in Chinese adults and assess whether socioeconomic or health system factors contribute to such differences. METHODS: In 2004–2008, the China Kadoorie Biobank recruited 512 726 adults from 10 diverse areas in China. Data for 38 928 first hospitalisations with IHD (2911 acute myocardial infarction (AMI), 9817 angina and 26 200 other IHD) were obtained by electronic linkage to health insurance records until 31 December 2016. Multivariate Poisson regression models were used to estimate women-to-men rate ratios (RRs) of having cardiac enzyme tests, coronary angiography and coronary revascularisation. RESULTS: Among the 38 928 individuals (61% women) with IHD admissions, women were less likely to have AMI (5% vs 12%), but more likely to have angina (26% vs 24%) or other IHD (69% vs 64%). For admissions with AMI, there were no differences in the use of cardiac enzymes between women and men (RR=1.00; 95% CI, 0.97 to 1.03), but women had lower use of coronary angiography (0.80, 0.68 to 0.93) and coronary revascularisation (0.85, 0.74 to 0.99). For angina, the corresponding RRs were: 0.97 (0.94 to 1.00), 0.66 (0.59 to 0.74) and 0.56 (0.47 to 0.67), respectively; while for other IHD, they were 0.97 (0.94 to 1.00), 0.87 (0.76 to 0.99) and 0.61 (0.51 to 0.73), respectively. Adjusting for socioeconomic and health system factors did not significantly alter the women-to-men RRs. CONCLUSIONS: Among Chinese adults hospitalised with acute IHD, women were less likely than men to have coronary angiography and revascularisation, but socioeconomic and health system factors did not contribute to these differences.