COVID-19 and Diabetes: What Should We Expect?

Abstract

Patients with diabetes are at increased risk of the severe course of the coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We read with great interest the article of Pfützner et al. 1 in the Journal of Diabetes Science and Technology (JDST). The authors pointed out the relationship between periodontal diseases, diabetes, and increased COVID-19 mortality. Along with the possibility of salivary gland infection, some reports on the literature have also shown hyposalivation and taste alterations in COVID-19 patients. In this letter, we would like to call the attention of the possible long-term oral consequences that individuals affected by COVID-19 may present, especially regarding diabetes. The SARS-CoV and the SARS-CoV-2 share similarities. Both viruses use angiotensin-converting enzyme 2 (ACE-2) as receptor for entry into target cells and transmembrane serine protease 2 for priming. 2 ACE-2 is expressed in several tissues, including salivary glands and pancreas. In the pancreas, the previous SARS-CoV was found to damage islets, reduce insulin release, and cause acute insulin-dependent diabetes mellitus. 3 It was reported that, after hospitalization, more than 50% of the patients with SARS-CoV infection became diabetic. 3 Interestingly, the SARS-CoV-2 infection was shown to cause ketosis or ketoacidosis and induced diabetic ketoacidosis for those with diabetes. 4 The SARS-CoV-2 could also infect and cause damage to α-cells and β-cells of the pancreas, aggravating its function. 5,6 Thus, it is possible that COVID-19 trigger diabetes in some individuals. Literature reports that patients with diabetes often present oral repercussions, including periodontal diseases and salivary gland dysfunction, among others. It is well known that oxidative stress plays an important role in diabetes. Oxidative stress has also been suggested as a link between diabetes and periodontal disease. Interestingly, literature also suggested oxidative stress as a player in COVID-19 infection. According to our group experience, the salivary glands present oxidative damage and disturbances in the metabolism and antioxidant 948041D STXXX10.

Periodontal Diseases and COVID-19: A Scoping Review

“…Six articles mentioned risk factors or comorbidities that may be common to COVID-19 and periodontal diseases. 15,21,22,25,29,32 One was a letter to the editor, 25 three were short reports, 15,21,29 and two were reviews (►Table 2). 22,32 Hypothesized Common Risk Factors and Comorbidities…”

“…27 Among the six for which this was not clearly indicated, we considered that five were short reports 12,15,16,19,21 -one of which reported an ongoing clinical trial, 16 and one was a review. 23 The information relating to the topic found in the papers was the SARS-CoV-2 entry mechanism, [12][13][14]16,18,21,[24][25][26][27][28][30][31][32]36 the mechanism of how periodontitis might influence the entry of SARS-CoV-2 into cells or might worsen COVID-19, [15][16][17][18][19]21,[23][24][25][26][27][28]30,[32][33][34][35][36] and antiviral targets to treat COVID-19 (►Table 1). 14,18,24,27…”

Meta-Analysis: The Effect of Diabetes Mellitus Comorbidity on the Risk of Death in Covid-19 Patients

“…SARS-CoV-2 infection has been shown to cause ketosis or ketoacidosis and to cause diabetic ketoacidosis in those with diabetes. SARS-CoV-2 can also infect and cause damage to α cells and β cells of the pancreas (Pedrosa et al, 2020).…”

Xerostomia and Taste Alterations in COVID-19

“…Even though the mechanism behind the quantitative and qualitative alterations in saliva of COVID-19 patient is still unclear, 5 the effect of the SARS-CoV-2 infection in the salivary glands is believed to contribute to explain these alterations. 3,6 It is worth to note, however, that the reported taste disturbances in patients with COVID-19 have only been subjective in nature, and it is not quite clear if these patients experience disturbances in their sense of taste or whether they are experiencing disturbances in flavor 3 .…”

“…8 Besides, it has been also hypothesized that alterations in saliva composition and flow could be directly or indirectly caused by SARS-CoV-2 infection in salivary glands could. 3,6 This might lead to both xerostomia and taste alterations. Overall, studies are still necessary to unveil the precise pathophysiological mechanism by which SARS-CoV-2 causes the reported xerostomia and taste disturbances.…”