Protective Effects of Home T2DM Treatment with Glucagon-Like Peptide-1 Receptor Agonists and Sodium-Glucose Co-transporter-2 Inhibitors Against Intensive Care Unit Admission and Mortality in the Acute Phase of the COVID-19 Pandemic: A Retrospective Observational Study in Italy.

INTRODUCTION: Type 2 diabetes mellitus (T2DM) is a relevant risk factor for severe forms of COVID-19 (SARS coronavrus 2 [SARS-CoV-2] disease 2019), and calls for caution because of the high prevalence of T2DM worldwide and the high mortality rates observed in patients with T2DM who are infected with SARS-CoV-2. People with T2DM often take dipeptidyl peptidase-4 inhibitors (DPP-4is), glucagon-like peptide-1 receptor agonists (GLP-1ras), or sodium-glucose co-transporter-2 inhibitors (SGLT-2is), all of which have clear anti-inflammatory effects. The study aimed to compare (i) the severity and duration of hospital stay between patients with T2DM categorized by pre-hospitalization drug class utilization and (ii) the COVID-19-related death rates of those three groups. METHODS: We designed an observational, retrospective, multi-center, population-based study and extracted the hospital admission data from the health care records of 1916 T2DM patients over 18 years old who were previously on GLP-1ra, SGLT-2i, or DPP-4i monotherapy and were hospitalized for COVID-19 (diagnosis based on ICD.9/10 codes) between January 2020 and December 2021 in 14 hospitals throughout Italy. We analyzed general data, pre-admission treatment schedules, date of admission or transfer to the intensive care unit (ICU) (i.e., the index date; taken as a marker of increased COVID-19 disease severity), and death (if it had occurred). Statistics analyzed the impact of drug classes on in-hospital mortality using propensity score logistic regressions for (i) those admitted to intensive care and (ii) those not admitted to intensive care, with a random match procedure used to generate a 1:1 comparison without diabetes cohort replacement for each drug therapy group by applying the nearest neighbor method. After propensity score matching, we checked the balance achieved across selected variables if a balance was ever achieved. We then used propensity score matching between the three drug classes to assemble a sample in which each patient receiving an SGLT-2i was matched to one on a GLP-1ra, and each patient on a DPP-4i was matched to one on a GLP-1ra, adjusting for covariates. We finally used GLP-1ras as references in the logistic regression. RESULTS: The overall mortality rate (MR) of the patients was 14.29%. The MR in patients with COVID was 53.62%, and it was as high as 42.42% in the case of associated T2DM, regardless of any glucose-lowering therapy. In those on DPP-4is, there was excess mortality; in those treated with GLP-1ras and SGLT-2is, the death rate was significantly lower, i.e., almost a quarter of the overall mortality observed in COVID-19 patients with T2DM. Indeed, the odds ratio (OR) in the logistic regression resulted in an extremely high risk of in-hospital death in individuals previously treated with DPP-4is [incidence rate (IR) 4.02, 95% confidence interval (CI) 2.2-5.7) and only a slight, nonsignificantly higher risk in those previously treated with SGLT-2is (IR 1.42, 95% CI 0.6-2.1) compared to those on GLP-1ras. Moreover, the longer the stay, the higher the death rate, which ranged from 22.3% for ≤ 3-day stays to 40.3% for 4- to 14-day stays (p < 0.01 vs. the former) and 77.4% for over-14-day stays (p < 0.001 vs. both the others). DISCUSSION: Our data do not support a protective role of DPP-4is; indeed, this role has already been questioned due to previous observations. However, the data do show a strong protective effect of SGLT-2is and GLP-1ras. Beyond lowering circulating glucose levels, those two drug classes were found to exert marked anti-phlogistic effects: SGLT-2is increased adiponectin and reduced urate, leptin, and insulin concentrations, thus positively affecting overall low-grade inflammation, and GLP-1ras may also greatly help at the lung tissue level, meaning that their extra-glycemic effects extend well beyond those acknowledged in the cardiovascular and renal fields. CONCLUSIONS: The aforedescribed observational clinical data relating to a population of Italian inpatients with T2DM suggest that GLP-1ras and SGLT-2is can be considered antidiabetic drugs of choice against COVID-19, and might even prove beneficial in the event of any upcoming pandemic that has life-threatening effects on the pulmonary and cardiovascular systems.

The Impact of GLP-1 RAs and DPP-4is on Hospitalisation and Mortality in the COVID-19 Era: A Two-Year Observational Study.

Novel antidiabetic drugs have the ability to produce anti-inflammatory effects regardless of their glucose-lowering action. For this reason, these molecules (including GLP-1 RAs and DPP-4is) were hypothesized to be effective against COVID-19, which is characterized by cytokines hyperactivity and multiorgan inflammation. The aim of our work is to explore the potential protective role of GLP-1 RAs and DPP-4is in COVID-19 (with the disease intended to be a model of an acute stressor) and non-COVID-19 patients over a two-year observation period. Retrospective and one-versus-one analyses were conducted to assess the impact of antidiabetic drugs on the need for hospitalization (in both COVID-19- and non-COVID-19-related cases), in-hospital mortality, and two-year mortality. Logistic regression analyses were conducted to identify the variables associated with these outcomes. Additionally, log-rank tests were used to plot survival curves for each group of subjects, based on their antidiabetic treatment. The performed analyses revealed that despite similar hospitalization rates, subjects undergoing home therapy with GLP-1 RAs exhibited significantly lower mortality rates, even over a two-year period. These individuals demonstrated improved survival estimates both within hospital and non-hospital settings, even during a longer observation period.