Diabetes Mellitus and SARS-CoV-2 Infection: Pathophysiologic Mechanisms and Implications in Management

Abstract

Introduction: Currently, diabetes mellitus (DM) as well as coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are major public health issues worldwide. Background: It has been suggested that patients with DM are more vulnerable to SARS-CoV-2 infection and suffer from more severe forms of the disease. Methods: A literature search was performed using PubMed, Scopus and Google search engines. Results: Angiotensin converting enzyme-2 (ACE2) is the major receptor of SARS-CoV-2 in the human host. The differential expression of ACE2 in the lungs of patients with DM makes them more susceptible to COVID-19. Additionally, acute or chronic hyperglycemia renders individuals in an immune-suppressive state, with impaired innate and adaptive immunity function, contributing also to the severity of COVID-19 infection among patients with DM. Other factors contributing to a more severe course of COVID-19 include the co-existence of obesity in T2DM; the endothelial inflammation induced by the SARS-CoV-2 infection, which aggravates the endothelial dysfunction observed in both T1DM and T2DM; and the hypercoagulability presented in COVID-19 infection that increases the thrombotic tendency in DM. Conclusion: This review summarizes the pathophysiologic mechanisms underlying the co-existence of both pandemics as well as the current recommendations and future perspectives regarding optimal treatment of inpatients and outpatients with DM in the era of SARS-CoV-2 infection. Notably, the current recommended drugs for the treatment of severe COVID-19, dexamethasone and remdesivir, may cause hyperglycemia, an adverse effect that physicians should bear in mind, when caring for patients with DM and COVID-19.

Ophthalmic Screening in Patients with Coronavirus Disease 2019: A Prospective Cohort Study

“…Pulmonary expression of ACE-2 (the major receptor for SARS-CoV-2), immunocompromised state, obesity, pre-existing endothelial dysfunction, and the tendency to hypercoagulability are all features that render diabetic patients more vulnerable to SARS-CoV-2 [29,30]. Among patients hospitalized for COVID-19, uncontrolled hyperglycemia and new-onset or deterioration of pre-existing T2D frequently occur [28].…”

“…Among patients hospitalized for COVID-19, uncontrolled hyperglycemia and new-onset or deterioration of pre-existing T2D frequently occur [28]. Furthermore, corticosteroids, which are recommended for the treatment of patients with COVID-19, are known to trigger hyperglycemia [30]. Moreover, ACE-2 is an inhibitor of the renin-angiotensin-aldosterone system, which is a major mediator in blood pressure regulation.…”

COVID-19 induces proatherogenic alterations in moderate to severe non-comorbid patients: A single-center observational study

“…Although our data do not determine whether the alterations observed during infection were also present before the infection, they were strictly related to the severity of the cases. Particularly, it is worth mentioning that some of the current clinical drugs used for COVID-19 treatment, such as dexamethasone and remdesivir, may cause hyperglycemia [53] worsening the situation. In addition, the difference observed amongst groups regarding the interval of days for blood collection could be due to individual variability in the manifestation of the symptoms and the time of searching for medical assistance, as well as in obtaining the Free and Informed Consent form signed.…”

The effect of COVID-19 pandemic on the attendance and clinical outcomes of patients with ophthalmic disease: A mini-review

“…During the lockdown period the number of patients attending regular follow-up visits or receiving intravitreal, laser or surgical treatments was significantly decreased compared to the same period of previous years, as presented in a number of publications from different countries. Furthermore, a significant percentage of patients with retinal disease have diabetes and/or obesity which are known risk factors for Covid-19 and these patients are often hesitant in attending their appointments [ 16 , 17 ].…”