Reduced pre-hospital and in-hospital survival rates after out-of-hospital cardiac arrest of patients with type-2 diabetes mellitus: an observational prospective community-based study

Aims Out-of-hospital cardiac arrest (OHCA) remains a major cause of death. We aimed to determine whether type-2 diabetes mellitus (T2DM) is associated with reduced pre-hospital and in-hospital survival rates after OHCA. Methods and results An observational community-based cohort study was performed among 1549 OHCA patients with ECG-documented ventricular tachycardia/ventricular fibrillation (VT/VF). We compared pre-hospital and in-hospital survival rates between T2DM patients and non-diabetic patients. Analyses among T2DM patients were stratified according to current T2DM treatment, used as proxy for T2DM severity. Proportions of neurologically intact survival were analysed. Pre-hospital survival rates were lower in T2DM patients (n = 275) than in non-diabetic patients (n = 1274); 48.7 vs. 55.8% (univariate P = 0.032). Type-2 diabetes mellitus was associated with lower pre-hospital survival [OR 0.75 (0.58-0.98); after evaluation of the risk factors, we found no relevant confounding]. Patients treated with insulin only had lower pre-hospital survival rates than patients treated with oral glucose-lowering drugs only (37.3 vs. 53.3%, univariate P = 0.034), partially explained by location of OHCA and EMS response time [ORadj 0.62 (0.33-1.17)]. In-hospital survival rates were also lower in T2DM patients (n = 134) than in non-diabetic patients (n = 711); 40.3 vs. 57.7%, univariate P < 0.001. In those patients whose cause ofOHCAwas retrieved (n = 771), T2DM was significantly associated with lower in-hospital survival [ORadj 0.57 (0.37-0.87)]. Neurologically intact status at discharge was similarly high among T2DM and nondiabetic patients (94.4 vs. 94.6%, P = 0.954). Conclusion T2DM is associated with lower pre-hospital and in-hospital survival rates after OHCA. Neurologically intact status at hospital discharge is high both among T2DM and non-diabetic patients.