Aman Rajpal, Leili Rahimi and Faramarz Ismail-Beigi
The Corona Virus Disease 2019(COVID-19) pandemic caused by the SARS-Cov-2 corona virus has affected millions of people globally with a higher rate of mortality in patients with Type 2 Diabetes Mellitus (T2DM). Several mechanisms have been suggested for the severity of COVID-19 illness in patients with diabetes including increased virus entry, decreased viral clearance, diminished T-cell function, increased susceptibility to high levels of inflammation and cytokine storm. Hyperglycemia and severe COVID-19 have been shown to have a bidirectional relationship. Hyperglycemia, even in the absence of diabetes, can lead to increased susceptibility for the infection as well as increased severity of COVID-19. In addition, patients with severe COVID-19 may exhibit extreme levels of hyperglycemia or new-onset diabetes, which has been associated with worse outcomes. Some recent data have also suggested a link between outpatient glycemic control (prior to the infection) and severity of COVID-19. The available evidence suggests that improved glycemic control, both prior to infection as well as during hospitalization, are important measure in reducing the risk of severe COVID-19.