COVID-19 and diabetes mellitus: An unholy interaction of two pandemics

Abstract

Background and aims: Diabetes mellitus is associated with poor prognosis in patients with COVID-19. On the other hand, COVID-19 contributes to worsening of dysglycemia in people with diabetes mellitus over and above that contributed by stress hyperglycemia. Herein, we have reviewed the two-way interactions between COVID-19 and diabetes mellitus.

Methods: We have performed an extensive literature search for articles in PubMed, EMBASE and Google Scholar databases till April 25, 2020, with the following keywords: "COVID-19", "SARS-CoV-2", "diabetes", "diabetes mellitus", "SARS", "infection" and "management of diabetes mellitus" with interposition of the Boolean operator "AND".

Results: Compromised innate immunity, pro-inflammatory cytokine milieu, reduced expression of ACE2 and use of renin-angiotensin-aldosterone system antagonists in people with diabetes mellitus contribute to poor prognosis in COVID-19. On the contrary, direct β-cell damage, cytokine-induced insulin resistance, hypokalemia and drugs used in the treatment of COVID-19 (like corticosteroids, lopinavir/ritonavir) can contribute to worsening of glucose control in people with diabetes mellitus.

Conclusions: The two-way interaction between COVID-19 and diabetes mellitus sets up a vicious cycle wherein COVID-19 leads to worsening of dysglycemia and diabetes mellitus, in turn, exacerbates the severity of COVID-19. Thus, it is imperative that people with diabetes mellitus take all necessary precautions and ensure good glycemic control amid the ongoing pandemic.

Keywords: COVID-19; Cytokines; Diabetes mellitus; T1DM; T2DM.

Fig. 1

Schematic diagram showing the two-way interaction between the novel coronavirus disease (COVID-19) and diabetes mellitus. Diabetes mellitus contributes to increased disease severity of COVID-19 via compromised innate immunity, exaggerated pro-inflammatory cytokine response and low expression of angiotensin-converting enzyme 2 (ACE2). In addition, use of angiotensin-converting enzyme inhibitors (ACEi)/angiotensin-receptor blockers (ARBs) in people with diabetes mellitus have widely been implicated in contributing to disease severity in COVID-19. On the other hand, COVID-19 leads to worsening of glucose control in people with diabetes mellitus perhaps by direct virus-mediated β-cell damage, augmentation of insulin resistance through cytokines and fetuin A and hypokalemia. In addition, drugs being used in the management of COVID-19 like corticosteroids and lopinavir/ritonavir can also contribute to dysglycemia.