An observational study of therapeutic procedures and in-hospital outcomes among patients admitted for acute myocardial infarction in Spain, 2016-2022: the role of diabetes mellitus.

Background: We used the Spanish national hospital discharge data from 2016 to 2022 to analyze procedures and hospital outcomes among patients aged ≥ 18 years admitted for ST-elevation myocardial infarction (STEMI) and non-ST-elevation myocardial infarction (NSTEMI) according to diabetes mellitus (DM) status (non-diabetic, type 1-DM or type 2-DM).

Methods: We built logistic regression models for STEMI/NSTEMI stratified by DM status to identify variables associated with in-hospital mortality (IHM). We analyzed the effect of DM on IHM.

Results: Spanish hospitals reported 201,950 STEMIs (72.7% non-diabetic, 0.5% type 1-DM, and 26.8% type 2-DM; 26.3% female) and 167,285 NSTEMIs (61.6% non-diabetic, 0.6% type 1-DM, and 37.8% type 2-DM; 30.9% female). In STEMI, the frequency of percutaneous coronary intervention (PCI) increased among non-diabetic people (60.4% vs. 68.6%; p < 0.001) and people with type 2-DM (53.6% vs. 66.1%; p < 0.001). In NSTEMI, the frequency of PCI increased among non-diabetic people (43.7% vs. 45.7%; p < 0.001) and people with type 2-DM (39.1% vs. 42.8%; p < 0.001). In NSTEMI, the frequency of coronary artery by-pass grafting (CABG) increased among non-diabetic people (2.8% vs. 3.5%; p < 0.001) and people with type 2-DM (3.7% vs. 5.0%; p < 0.001). In the entire population, lower IHM was associated with undergoing PCI (odds ratio [OR] [95% confidence interval] = 0.34 [0.32-0.35] in STEMI; 0.24 [0.23-0.26] in NSTEMI) or CABG (0.33 [0.27-0.40] in STEMI; 0.45 [0.38-0.53] in NSTEMI). IHM decreased over time in STEMI (OR = 0.86 [0.80-0.93]). Type 2-DM was associated with higher IHM in STEMI (OR = 1.06 [1.01-1.11]).

Conclusions: PCI and CABG were associated with lower IHM in people admitted for STEMI/NSTEMI. Type 2-DM was associated with IHM in STEMI.