In-Hospital Mortality and Predictors Among People with Diabetes in Lubumbashi, Democratic Republic of the Congo: A Prospective Observational Study

Background: Diabetes mellitus (DM) is a growing public health challenge in sub-Saharan Africa, where limited diagnostic capacity and delayed care contribute to high morbidity and mortality. However, data on in-hospital mortality determinants among people with diabetes in the Democratic Republic of the Congo (DRC) are scarce. This study assessed in-hospital mortality and predictors among people with diabetes admitted to tertiary hospitals in Lubumbashi. Methods: A prospective observational cohort study was conducted over 20 months (January 2022-August 2023) in three hospitals in Lubumbashi. A total of 324 adults (≥18 years) with confirmed DM were enrolled and prospectively followed from hospital admission until discharge or death. Sociodemographic, clinical, laboratory, and treatment-related data were collected using standardised forms. The primary outcome was in-hospital mortality within 60 days of admission. Kaplan-Meier analysis was performed to estimate 60-day survival, and the Log rank test was used to compare survival distributions. Cox proportional hazards regression identified independent predictors of mortality, with adjusted hazard ratios (aHRs) and 95% confidence intervals (95% CIs) reported. Results: Of the 324 hospitalised people with diabetes, 41 deaths occurred, yielding an in-hospital mortality rate of 12.7%. The deceased patients had a mean time to death of 4.9±4.1 days. The overall restricted mean survival time for the cohort was 53.0±1.0 days. Several factors were independently associated with increased mortality: older age (aHR=1.05; 95% CI: 1.03-1.09; p