Risk Factors for COVID-19: Diabetes, Hypertension, and Obesity

Introduction: The recent global pandemic of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has involved more than 7 million people worldwide and been associated with more than 400,000 deaths. No clear information is known about all the potential risk factors for COVID-19 or what factors adversely influence its clinical course and mortality. Therefore, we analyzed the role of obesity, type 2 diabetes, and hypertension as risk factors for COVID-19. Methods: We identified articles for inclusion by searching PubMed and Google Scholar (last accessed 15 June 2020). Retrospective review of literature. Analysis of epidemiological data concerning obesity prevalence and COVID-19 incidence, particularly in Italy and the USA. Results: Data from several retrospective studies of prevalence showed that patients with hypertension, type 2 diabetes, and obesity may have more severe COVID-19, intensive care unit admission, and higher mortality rates, but it is not definitively clear if this is an independent association. In general, the prevalence of obesity in patients with COVID-19 seems to bethe same as that of the general population throughout the world; however, obesity seems to be associated with more severe disease and mortality in younger (< 60 years) patients. Similar effects seem to occur in patients with diabetes and/or hypertension but at older ages (> 60 years). In strict connection, it has been proposed that the use of drugs inhibiting angiotensin-converting enzyme 2 (ACE-2) or dipeptidyl dipeptidase 4 (DPP-4) might influence viral activity and disease severity since ACE-2 and DPP-4 receptors mediate SARS-CoV- 2 entry into the host cells; however, no evidence exists to date that shows that this may be the case. Conclusion: Overall, diabetes, hypertension, and obesity seem to negatively affect the clinical course and disease outcome in patients with COVID-19. However, these data need further confirmation by studies with more accurate data registration.