The Effect of Diabetes Mellitus on Outcomes of Patients Admitted with COVID-19

Background and Objectives: Diabetes mellitus is associated with poor clinical outcomes in patients with coronavirus disease 2019 (COVID-19). This study aimed to explore the clinical characteristics of patients with type 2 diabetes with COVID-19, and to determine the impact of type 2 diabetes on clinical outcome of patients with COVID-19. Material and Methods: This single-center, retrospective, observational study enrolled patients admitted from March 2020 to June 2021 with COVID-19. The clinical and biochemical characteristics of patients with known type 2 diabetes, newly diagnosed diabetes, type 2 diabetes with comorbidities and those who succumbed to illness were analyzed. Results: Of 4,559 patients with COVID-19, 2,090 (45.8%) had type 2 diabetes. Patients with COVID-19 with diabetes were older, more likely to receive mechanical ventilation, had higher odds of mortality from COVID-19 as compared with patients without diabetes. In addition, patients with diabetes had significantly higher levels of serum creatinine, C-reactive protein, ferritin, lactate dehydrogenase, and D-dimer. Compared with previously diagnosed patients with diabetes, newly diagnosed patients had higher mortality (33% vs. 27%, P = 0.049). Among patients with COVID-19 and diabetes, nonsurvivors had significantly higher levels of inflammatory markers and had severe impairment of cardiac, renal, and coagulation parameters as opposed to survivors. Conclusion: Patients with COVID-19 with diabetes were more likely to have severe disease and had higher mortality. Presence of chronic kidney disease and coronary artery disease in patients with diabetes with COVID-19 was associated with adverse outcome. Patients with newly diagnosed diabetes had higher odds of severe disease at presentation and had higher mortality.