Does poor glucose control increase the severity and mortality in patients with diabetes and COVID-19?

Diabetes in often associated with an increased severity and mortality in patients with COVID-19. We aimed to find out whether the severity and mortality in patients with diabetes with COVID-19 has any correlation to the level of glycemic control.

A Boolean search was made in PubMed database using the specific keywords related to our objectives up till May 14, 2020 and full text of article retrieved with the supplements published in English language.

Two studies available so far have studied the outcomes of severity and mortality in patients with diabetes stratified on glycemic control. Both the studies have unequivocally found that patients with poorly-controlled hyperglycemia (blood glucose >180 mg/dl) have significantly higher level of poor prognostic markers biochemically, compared to the well-controlled arms (blood glucose <180 mg/dl). Moreover, significant increase in severity and mortality was observed in cohorts with poorly-controlled blood glucose due to any cause (diabetes or stress hyperglycemia), compared to the well-controlled cohorts with COVID-19, even after the adjustment of multiple confounders.

Poorly-controlled hyperglycemia increases the severity and mortality in patients with COVID-19. All treating physician must strive for a good glycemic control (blood glucose <180 mg/dl) in patients with or without diabetes.