Chronic dysglycemia and risk of SARS-CoV-2 associated respiratory failure in hospitalised patients.

Background Diabetes is common among patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-induced respiratory failure. We aimed to investigate the relationship between different stages of chronic dysglycemia and development of respiratory failure in hospitalised SARS-CoV-2 positive patients. Methods In this retrospective observational study, we included 385 hospitalised SARS-CoV-2 positive patients at Karolinska University Hospital, Sweden with an HbA1c test obtained within 3 months before admission. Based on HbA1c level and previous diabetes history, we classified patients into the following dysglycemia categories: prediabetes, unknown diabetes, controlled diabetes or uncontrolled diabetes. We used multivariable logistic regression analysis adjusted for age, sex and body mass index, to assess the association between dysglycemia categories and development of SARS-CoV-2-induced respiratory failure. Results Of the 385 study patients, 88 (22.9%) had prediabetes, 68 (17.7%) had unknown diabetes, 36 (9.4%) had controlled diabetes, and 83 (21.6%) had uncontrolled diabetes. Overall, 299 (77.7%) patients were admitted with or developed SARS-CoV-2-induced respiratory failure during hospitalisation. In multivariable logistic regression analysis compared with no chronic dysglycemia, prediabetes (OR 14.41, 95% CI 5.27-39.43), unknown diabetes (OR 15.86, 95% CI 4.55-55.36), and uncontrolled diabetes (OR 17.61, 95% CI 5.77-53.74) was independently associated with increased risk of SARS-CoV-2-induced respiratory failure. Conclusion In our cohort of hospitalised SARS-CoV-2 positive patients with available HbA1c data, prediabetes, undiagnosed diabetes and poorly controlled diabetes were associated with a markedly increased risk of SARS-CoV-2-associated respiratory failure.