Outcomes in Patients With Hyperglycemia Affected by COVID-19: Can We Do More on Glycemic Control?

OBJECTIVE: An important prognostic factor in any form of infection seems to be glucose control in patients with type 2 diabetes. There is no information about the effects of tight glycemic control on coronavirus disease 2019 (COVID-19) outcomes in patients with hyperglycemia. Therefore, we examined the effects of optimal glycemic control in patients with hyperglycemia affected by COVID-19. RESEARCH DESIGN AND METHODS: Fifty-nine patients with COVID-19 hospitalized with moderate disease were evaluated. On the basis of admission glycemia >7.77 mmol/L, patients were divided into hyperglycemic and normoglycemic groups. Interleukin 6 (IL-6) and D-dimer levels were evaluated at admission and weekly during hospitalization. The composite end point was severe disease, admission to an intensive care unit, use of mechanical ventilation, or death. RESULTS: Thirty-four (57.6%) patients were normoglycemic and 25 (42.4%) were hyperglycemic. In the hyperglycemic group, 7 (28%) and 18 (72%) patients were diagnosed with diabetes already before admission, and 10 (40%) and 15 (60%) were treated without and with insulin infusion, respectively. The mean of glycemia during hospitalization was 10.65 ± 0.84 mmol/L in the no insulin infusion group and 7.69 ± 1.85 mmol/L in the insulin infusion group. At baseline, IL-6 and D-dimer levels were significantly higher in the hyperglycemic group than in the normoglycemic group (P < 0.001). Even though all patients were on standard treatment for COVID-19 infection, IL-6 and D-dimer levels persisted higher in patients with hyperglycemia during hospitalization. In a risk-adjusted Cox regression analysis, both patients with hyperglycemia and patients with diabetes had a higher risk of severe disease than those without diabetes and with normoglycemia. Cox regression analysis evidenced that patients with hyperglycemia treated with insulin infusion had a lower risk of severe disease than patients without insulin infusion. CONCLUSIONS: Insulin infusion may be an effective method for achieving glycemic targets and improving outcomes in patients with COVID-19.