Factors leading to high morbidity and mortality of COVID-19 in patients with type 2 diabetes.

Coronavirus disease 2019 (COVID-19) is a recent pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a novel coronavirus. Diabetes (mostly type 2 diabetes mellitus, T2DM) and hyperglycemia are among the major comorbidities in patients with COVID-19 leading to poor outcomes. Reports show that patients with diabetes and COVID-19 are at an increased risk for developing severe complications including acute respiratory distress syndrome, multi-organ failure, and death. Here we explore potential mechanistic links that could explain the observed higher morbidity and mortality in this patient population. Patients with T2DM have an underlying increased level of inflammation associated with obesity and insulin resistance in addition to other comorbidities including hypertension, obesity, cardiovascular disease, dyslipidemia, and being older. We review evidence that T2DM with hyperglycemia are among factors that lead to elevated expression of angiotensin-converting enzyme 2 (ACE2) in lungs and other tissues; ACE2 is the cellular "receptor" and port of viral entry. The preexisting chronic inflammation with augmented inflammatory response to the infection and the increasing viral load leads to extreme systemic immune response ("cytokine storm") that is strongly associated with increased severity of COVID-19. Based on the available evidence, it is recommended by a panel of experts that safe but stringent control of blood glucose, blood pressure, and lipids be carried out in patients with T2DM, measures that could potentially serve to decrease the severity of COVID-19 should these patients contract the viral infection. Once the infection occurs, then attention should be directed to proper glycemic control with use of insulin and frequent monitoring of blood glucose levels.

Challenging Issues in the Management of Cardiovascular Risk Factors in Diabetes During the COVID-19 Pandemic: A Review of Current Literature.

The COVID-19 outbreak was declared a pandemic on March 2020. Many patients with SARS-CoV-2 infection have underlying chronic medical conditions such as diabetes, cardiovascular disease (CVD), and hypertension. Patient-related outcomes are worse if there are associated comorbidities. We do not have enough evidence regarding the most appropriate management of patients with diabetes during COVID-19 infection. Insulin resistance and CVD together increase the inflammatory state of the body, which can contribute to and perhaps mediate the increase of COVID-19 severity. Hence, in addition to management of dysglycemia, other CVD risk factors should be targeted. We explore the possible pathophysiologic links between diabetes and COVID-19 and discuss various options to treat dysglycemia, hypertension, and dyslipidemia in the era of COVID-19.