Abstract: Diabetes, Metabolic Syndrome and Obesity: Targets and Therapy Dovepress open access to scientific and medical research Diabetes, Metabolic Syndrome and Obesity For personal use only. Open Access Full Text Article ORIGINAL RESEARCH Infection Rates and Impact of Glucose Lowering Medications on the Clinical Course of COVID-19 in People with Type 2 Diabetes: A Retrospective Observational Study Francesca Mannucci 1 , Giacomo Vitturi 2 , Luca Benacchio 3 , Luca Gino Sbrogiò 4 , Francesca Bano 1 , Annunziata Lapolla 5 , Francesco Piarulli 5 , Maria Cecilia Giron 2 , Angelo Avogaro 6 , Gian Paolo Fadini 6 1 Pharmaceutical Unit, Local Health Unit 6, Padua, Italy; 2Department of Pharmaceutical and Pharmacological Sciences, University of Padova, Padua, Italy; 3Epidemiologic Unit, Local Health Unit 6, Padua, Italy; 4Prevention Department Local Health Unit 6, Padua, Italy; 5Diabetology Service, Local Health Unit 6, Padua, Italy; 6Department of Medicine, University of Padova, Padua, Italy Correspondence: Gian Paolo Fadini, Department of Medicine, University of Padova, Via Giustiniani 2, Padova, 35128, Italy, Tel +39 049 8214318, Fax +39 049 8212184, Email gianpaolo.fadini@unipd.it Purpose: Diabetes is a risk factor for COVID-19 severity, but the role played by glucose lowering medications (GLM) is still unclear. The aim of this study was to assess infection rates and outcomes of COVID-19 (hospitalization and mortality) in adults with diabetes assisted by the Local Health Unit of Padua (North-East Italy) according to the ongoing GLM. Patients and Methods: People with diabetes were identified using administrative claims, while those with SARS-CoV-2 infection were detected by cross referencing with the local COVID-19 surveillance registry. A multivariate logistic regression model was used to verify the association between GLM classes and the outcome. Results: SARS-CoV-2 infection rates were marginally but significantly higher in individuals with diabetes as compared to those without diabetes (RR 1.04, p = 0.043), though such relative 4% increase may be irrelevant from a clinical and epidemiological perspective. 1923 individuals with GLM-treated diabetes were diagnosed with COVID-19; 456 patients were hospitalized and 167 died. Those treated with insulin had a significantly higher risk of hospitalizations for COVID-19 (OR 1.48 p < 0.01) as were those treated with sulphonylureas/glinides (OR 1.34, p = 0.02). Insulin use was also significantly associated with higher mortality (OR 1.90, p < 0.01). Use of metformin was significantly associated with lower death rates (OR 0.62, p = 0.02). The association of other GLM classes with the outcome was not significant. Conclusion: Diabetes does not appear to modify the risk of SARS-CoV-2 infection in a clinically meaningful way, but strongly increases the rates of hospitalization and death. Insulin use was associated with worse outcomes, whereas metformin use was associated with lower mortality. Keywords: diabetes mellitus, SARS-CoV-2, antidiabetic drugs, metformin, hospitalization, odds ratio, administrative claims, Veneto