Impact of diabetes mellitus on clinical outcomes in patients affected by Covid-19

Abstract

A possible association could exist between type 2 diabetes mellitus (T2DM) and Coronavirus-19 (Covid-19) infection. Indeed, patients with T2DM show high prevalence, severity of disease and mortality during Covid-19 infection. However, the rates of severe disease are significantly higher in patients with diabetes compared with non-diabetes (34.6% vs. 14.2%; p < 0.001). Similarly, T2DM patients have higher rates of need for Intensive Care Unit (ICU, 37.0% vs. 26.7%; p = 0.028). Thus, about the pneumonia of Covid-19, we might speculate that the complicated alveolar-capillary network of lungs could be targeted by T2DM micro-vascular damage. Therefore, T2DM patients frequently report respiratory symptoms and are at increased risk of several pulmonary diseases. In addition, pro-inflammatory pathways as that involving interleukin 6 (IL-6), could be a severity predictor of lung diseases. Therefore, it looks intuitive to speculate that this condition could explain the growing trend of cases, hospitalization and mortality for patients with T2DM during Covid-19 infection. To date, an ongoing experimental therapy with monoclonal antibody against the IL-6 receptor in Italy seems to have beneficial effects on severe lung disease and prognosis in patients with Covid-19 infection. Therefore, should patients with T2DM be treated with more attention to glycemic control and monoclonal antibody against the IL-6 receptor during the Covid-19 infection?

Keywords: Covid-19; Micro-vascular disease; Several disease; Type 2 diabetes mellitus.

Fig. 1

Proportion of severity endpoints among main recent studies. We performed a broad literature research in PubMed up to March 12, 2020. All articles dealing with coronavirus disease 2019 were screened. Main studies reporting characteristics and outcomes of patients affected by coronavirus disease with data referring to those with or without diabetes were extracted. Summary proportion estimates of the outcomes of interest were pooled, using inverse-variance weights obtained from a random-effects meta-analysis with 95% confidence interval. Statistical significance was set at p < 0.05. All analyses were performed in Open Meta-Analyst. In the study by Young et al., data stratified by diabetes referred to patients requiring or not requiring supplemental O2, which included but was not restricted to Intensive Care Unit (ICU)