Immunogenicity and Safety of SARS-CoV-2 mRNA Vaccines in a Cohort of Patients With Type 1 Diabetes.

Patients with type 1 diabetes (T1D) may develop severe outcomes during coronavirus disease 2019 (COVID-19), but their ability to generate an immune response against the SARS-CoV-2 mRNA vaccines remains to be established. We evaluated the safety, immunogenicity, and glycometabolic effects of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccines in patients with T1D. A total of 375 patients (326 with T1D and 49 subjects without diabetes) who received two doses of the SARS-CoV-2 mRNA vaccines (mRNA-1273, BNT162b2) between March and April 2021 at ASST Fatebenefratelli Sacco were included in this monocentric observational study. Local and systemic adverse events were reported in both groups after SARS-CoV-2 mRNA vaccination, without statistical differences between them. While both patients with T1D and subjects without diabetes exhibited a parallel increase in anti-SARS-CoV-2 spike titers after vaccination, the majority of patients with T1D (70% and 78%, respectively) did not show any increase in the SARS-CoV-2-specific cytotoxic response compared with the robust increase observed in all subjects without diabetes. A reduced secretion of the T-cell-related cytokines interleukin-2 and tumor necrosis factor-α in vaccinated patients with T1D was also observed. No glycometabolic alterations were evident in patients with T1D using continuous glucose monitoring during follow-up. Administration of the SARS-CoV-2 mRNA vaccine is associated with an impaired cellular SARS-CoV-2-specific cytotoxic immune response in patients with T1D.

Indirect and Direct Effects of SARS-CoV-2 on Human Pancreatic Islets.

Recent studies have shown that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection may induce metabolic distress, leading to hyperglycemia in patients affected by coronavirus disease 19 (COVID-19). We investigated the potential indirect and direct effects of SARS-CoV-2 on human pancreatic islets in 10 patients who became hyperglycemic after COVID-19. Although there was no evidence of peripheral anti-islet autoimmunity, the serum of these patients displayed toxicity on human pancreatic islets, which could be abrogated by the use of anti-interleukin-1ß (IL-1ß), anti-IL-6, and anti-tumor necrosis factor α, cytokines known to be highly upregulated during COVID-19. Interestingly, the receptors of those aforementioned cytokines were highly expressed on human pancreatic islets. An increase in peripheral unmethylated INS DNA, a marker of cell death, was evident in several patients with COVID-19. Pathology of the pancreas from deceased hyperglycemic patients who had COVID-19 revealed mild lymphocytic infiltration of pancreatic islets and pancreatic lymph nodes. Moreover, SARS-CoV-2-specific viral RNA, along with the presence of several immature insulin granules or proinsulin, was detected in postmortem pancreatic tissues, suggestive of ß-cell-altered proinsulin processing, as well as ß-cell degeneration and hyperstimulation. These data demonstrate that SARS-CoV-2 may negatively affect human pancreatic islet function and survival by creating inflammatory conditions, possibly with a direct tropism, which may in turn lead to metabolic abnormalities observed in patients with COVID-19.

Acute and long-term disruption of glycometabolic control after SARS-CoV-2 infection.

Patients with coronavirus disease 2019 (COVID-19) are reported to have a greater prevalence of hyperglycaemia. Cytokine release as a consequence of severe acute respiratory syndrome coronavirus 2 infection may precipitate the onset of metabolic alterations by affecting glucose homeostasis. Here we describe abnormalities in glycometabolic control, insulin resistance and beta cell function in patients with COVID-19 without any pre-existing history or diagnosis of diabetes, and document glycaemic abnormalities in recovered patients 2 months after onset of disease. In a cohort of 551 patients hospitalized for COVID-19 in Italy, we found that 46% of patients were hyperglycaemic, whereas 27% were normoglycaemic. Using clinical assays and continuous glucose monitoring in a subset of patients, we detected altered glycometabolic control, with insulin resistance and an abnormal cytokine profile, even in normoglycaemic patients. Glycaemic abnormalities can be detected for at least 2 months in patients who recovered from COVID-19. Our data demonstrate that COVID-19 is associated with aberrant glycometabolic control, which can persist even after recovery, suggesting that further investigation of metabolic abnormalities in the context of long COVID is warranted.

Sitagliptin Treatment at the Time of Hospitalization Was Associated With Reduced Mortality in Patients With Type 2 Diabetes and COVID-19: A Multicenter, Case-Control, Retrospective, Observational Study.

OBJECTIVE: Poor outcomes have been reported in patients with type 2 diabetes and coronavirus disease 2019 (COVID-19); thus, it is mandatory to explore novel therapeutic approaches for this population. RESEARCH DESIGN AND METHODS: In a multicenter, case-control, retrospective, observational study, sitagliptin, an oral and highly selective dipeptidyl peptidase 4 inhibitor, was added to standard of care (e.g., insulin administration) at the time of hospitalization in patients with type 2 diabetes who were hospitalized with COVID-19. Every center also recruited at a 1:1 ratio untreated control subjects matched for age and sex. All patients had pneumonia and exhibited oxygen saturation <95% when breathing ambient air or when receiving oxygen support. The primary end points were discharge from the hospital/death and improvement of clinical outcomes, defined as an increase in at least two points on a seven-category modified ordinal scale. Data were collected retrospectively from patients receiving sitagliptin from 1 March through 30 April 2020. RESULTS: Of the 338 consecutive patients with type 2 diabetes and COVID-19 admitted in Northern Italy hospitals included in this study, 169 were on sitagliptin, while 169 were on standard of care. Treatment with sitagliptin at the time of hospitalization was associated with reduced mortality (18% vs. 37% of deceased patients; hazard ratio 0.44 [95% CI 0.29-0.66]; P = 0.0001), with an improvement in clinical outcomes (60% vs. 38% of improved patients; P = 0.0001) and with a greater number of hospital discharges (120 vs. 89 of discharged patients; P = 0.0008) compared with patients receiving standard of care, respectively. CONCLUSIONS: In this multicenter, case-control, retrospective, observational study of patients with type 2 diabetes admitted to the hospital for COVID-19, sitagliptin treatment at the time of hospitalization was associated with reduced mortality and improved clinical outcomes as compared with standard-of-care treatment. The effects of sitagliptin in patients with type 2 diabetes and COVID-19 should be confirmed in an ongoing randomized, placebo-controlled trial.