Impact of type 1 diabetes mellitus on mortality rate and outcome of hospitalized patients with myocardial infarction

INTRODUCTION: Type 1 diabetes mellitus (T1D) is associated with an increased cardiovascular risk. We aimed to investigate the influence of T1D on myocardial infarction (MI) patients' mortality. MATERIALS AND METHODS: The German nationwide inpatient sample 2005-2016 was used for statistical analysis. Hospitalized MI patients were stratified for T1D and impact of T1D on in-hospital outcomes was investigated. RESULTS: In total, 3,307,703 hospitalizations of MI patients (37.6 % females, 56.8 % aged ≥70 years) were counted in Germany 2005-2016 and included in this analysis. In 18,625 (0.6 %) of the cases additionally T1D was coded. Overall, 410,737 (12.4 %) in-hospital deaths occurred within the investigation period. MI patients with T1D were younger (64.0 [IQR 52.0-75.0] vs. 73.0 [62.0-81.0] years, P < 0.001), more often female (38.7 % vs. 37.6 %, P < 0.001) and obese (13.2 % vs. 9.3 %, P < 0.001). Comorbidities like peripheral arterial (14.2 % vs. 6.4 %, P < 0.001) and kidney disease (38.5 % vs. 27.2 %, P < 0.001) were more prevalent in MI patients with T1D. T1D was an independent risk factor for in-hospital death (OR 1.23 [95%CI 1.18-1.29], P < 0.001), recurrent MI (OR 1.56 [95%CI 1.35-1.80], P < 0.001), and stroke (OR 1.75 [95%CI 1.63-1.88], P < 0.001). While percutaneous coronary intervention (PCI, 37.8 % vs. 42.0 %, P < 0.001) was less often, coronary artery bypass grafting (CABG, 7.4 % vs. 4.6 %, P < 0.001) was more often performed in MI patients with T1D, confirmed by regression analysis (PCI: OR 0.66 [95%CI 0.64-0.68], P < 0.001; CABG: OR 1.54 [95%CI 1.45-1.63], P < 0.001). CONCLUSIONS: T1D represents an important and independent risk factor for mortality in MI patients. The results emphasize the high vulnerability of T1D patients who suffer from MI.