Are there sex differences in the effect of type 2 diabetes in the incidence and outcomes of myocardial infarction? A matched-pair analysis using hospital discharge data

BACKGROUND: To analyze incidence, use of therapeutic procedures, and in-hospital outcomes in patients with ST elevation myocardial infarction (STEMI) and non-ST elevation myocardial infarction (NSTEMI) according to the presence of type 2 diabetes (T2DM) in Spain (2016–2018) and to investigate sex differences. METHODS: Using the Spanish National Hospital Discharge Database, we estimated the incidence of myocardial infarctions (MI) in men and women with and without T2DM aged ≥ 40 years. We analyzed comorbidity, procedures, and outcomes. We matched each man and woman with T2DM with a non-T2DM man and woman of identical age, MI code, and year of hospitalization. Propensity score matching was used to compare men and women with T2DM. RESULTS: MI was coded in 109,759 men and 44,589 women (30.47% with T2DM). The adjusted incidence of STEMI (IRR 2.32; 95% CI 2.28–2.36) and NSTEMI (IRR 2.91; 95% CI 2.88–2.94) was higher in T2DM than non-T2DM patients, with higher IRRs for NSTEMI in both sexes. The incidence of STEMI and NSTEMI was higher in men with T2DM than in women with T2DM. After matching, percutaneous coronary intervention (PCI) was less frequent among T2DM men than non-T2DM men who had STEMI and NSTEMI. Women with T2DM and STEMI less frequently had a code for PCI that matched that of non-T2DM women. In-hospital mortality (IHM) was higher among T2DM women with STEMI and NSTEMI than in matched non-T2DM women. In men, IHM was higher only for NSTEMI. Propensity score matching showed higher use of PCI and coronary artery bypass graft and lower IHM among men with T2DM than women with T2DM for both STEMI and NSTEMI. CONCLUSIONS: T2DM is associated with a higher incidence of STEMI and NSTEMI in both sexes. Men with T2DM had higher incidence rates of STEMI and NSTEMI than women with T2DM. Having T2DM increased the risk of IHM after STEMI and NSTEMI among women and among men only for NSTEMI. PCI appears to be less frequently used in T2DM patients After STEMI and NSTEMI, women with T2DM less frequently undergo revascularization procedures and have a higher mortality risk than T2DM men. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12933-021-01273-y.