Diabetes mellitus and HbA1c as predictors of mortality in hospitalized COVID-19 patients

The role of diabetes mellitus (DM) in hospitalized COVID-19 patients and of HbA1c in hospitalized COVID-19 patients with DM were not studied adequately in the past. It was a retrospective cohort study. In this study, data from 305 hospitalized COVID-19 patients was analyzed. The study objective was to determine the association of DM with in-hospital mortality in COVID-19 patients. Another study objective was to determine the association of HbA1c with mortality in COVID-19 patients with DM. In this retrospective study, DM was present in 41.3% (126/305) of the study population. The multivariate Cox regression analysis showed a significant association between DM and mortality (adjusted hazard ratio (aHR): 2.116, 95% CI: 1.088–4.116, p = 0.027). The median HbA1c in diabetic patients was 8.9% (7.5-11.0). HbA1c was found to be associated with mortality in diabetic patients in the multivariate cox-regression analysis (aHR:1.272, 95% CI: 1.028–1.574, p = 0.027). The multivariate Cox regression analysis also showed the association of HbA1c (10.5%≤HbA1c > 10.5%) as a dichotomous variable with in-hospital mortality (aHR: 2.53, 95% CI: 2.606–194.81, p = 0.005) in diabetic patients. DM was independently associated with mortality in hospitalized COVID-19 patients in the multivariate analysis. In COVID-19 patients with DM, HbA1c was associated with mortality as a continuous and dichotomous variable in the multivariate analysis.