Study of new onset hyperglycemia and insulin resistance in COVID-19 patients

Background: COVID-19 has been associated with new onset hyperglycemia and insulin resistance, even in patients without pre-existing diabetes. This study aimed to evaluate the prevalence and characteristics of new onset hyperglycemia and insulin resistance in COVID-19 patients. Methods: This case-control study included 90 COVID-19 patients admitted to Era’s Lucknow Medical College and Hospital. Patients were divided into a case group with new onset hyperglycemia (n=57) and a control group with normoglycemia (n=33). Fasting blood glucose, post-prandial glucose, HbA1c, fasting insulin, and HOMA-IR were measured. Disease severity and outcomes were also assessed. Results: The prevalence of new onset hyperglycemia was 61.1% among COVID-19 patients. The case group had significantly higher mean fasting glucose (132.11 versus 90.43 mg/dl, p<0.001), post-prandial glucose (212.53 versus 157.91 mg/dl, p<0.001), HbA1c (5.86% versus 4.03%, p<0.001), fasting insulin (9.24 versus 7.67 μU/ml, p=0.004), and HOMA-IR (2.99 versus 1.72, p<0.001) compared to controls. Insulin resistance was present in 71.9% of cases versus 0% of controls (p<0.001). There was no significant difference in disease severity or mortality between groups. Conclusions: New onset hyperglycemia and insulin resistance are common in COVID-19 patients, even without pre-existing diabetes. This metabolic dysregulation may contribute to worse outcomes and requires further study. Glucose monitoring and management should be considered in all hospitalized COVID-19 patients.