Review Article

COVID-19 and Diabetes


Following the discovery of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in China, it has been transmitted to travelers through respiratory droplets and distributed worldwide. Viral, environmental, and host factors all play a role in getting infected with the virus and having severe forms of the disease named coronavirus disease 2019 (COVID-19). Diabetes is one of the most important host risk factors in the progression and severity of COVID-19. In diabetes, hyperglycemia and protein glycosylation increase pro-inflammatory cytokines levels and suppress innate and adaptive immune system by impairing the function of neutrophils, macrophages, and lymphocytes, especially regulatory T lymphocytes. The compromised immune system in diabetic patients makes them vulnerable to infectious diseases like COVID-19. Correspondingly, people with diabetes are usually treated with angiotensin-converting enzyme (ACE) inhibitors and angiotensin II Type-I receptor blockers (ARBs), which increase ACE2 expression as a receptor for SARS-CoV-2. Thus, diabetic patients are more likely to develop severe forms of COVID-19 and die due to chronic inflammation and impaired immune function.

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IssueVol 61 No 5 (2023) QRcode
SectionReview Article(s)
SARS-CoV-2 COVID-19 host risk factors diabetes

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Asgharzadeh V, Valiollahzadeh MR, Taghinejad Z, Asgharzadeh M, Rashedi J, Mahdavi poor B, Jalaei Nobari H, Ali Khalili A, Khairy Y, Mir Mazhari AA. COVID-19 and Diabetes. Acta Med Iran. 2023;61(5):257-263.