Management of diabetes in patients with COVID-19

Stefan Bornstein and colleagues¹ seem to be the first to react to an unprecedented challenge regarding management of diabetes in patients with COVID-19 by offering practical recommendations. The authors state that patients with diabetes have an increased risk of severe COVID-19 complications, including acute respiratory distress syndrome.

Because the practical recommendations also state that ACE2 has been identified as the receptor for the spike protein of severe acute respiratory syndrome coronavirus 2, Bornstein and colleagues discuss whether medications that increase ACE2 expression (ACE inhibitors and angiotensin II receptor blockers)² should be continued or discontinued for patients with COVID-19.

Bornstein and colleagues also mention that chronic hyperglycaemia downregulates ACE2 expression. However, the results of clinical observations are controversial; patients with diabetes have shown higher circulating ACE2 activities,³ yet ACE2 expression, according to renal biopsy data in patients with type 2 diabetes and kidney, disease is low.⁴ Differences in results might be due to drug effects. Of note, clinical and experimental data indicate that diabetes is protective against the development of acute respiratory distress syndrome.⁵ Thus, the recommended therapeutic aims for patients with diabetes and COVID-19 (plasma glucose concentration of 4–8 mmol/L and HbA_1c <53 mmol/mol [7%])¹ might end up being too strict. In addition, the recommendations do not mention glucose-lowering drugs as a possible specific influence on the expression of ACE2 and progression of COVID-19, which is currently a topic of discussion. Preliminary answers to most questions regarding diabetes and COVID-19 cannot be obtained earlier than the results of the first observational epidemiological studies, which should be the basis for clinical recommendations.