Association Between HbA1c and Clinical Severity Among Hospitalized COVID-19 Patients at the University of Lahore Teaching Hospital

Abstract

Background: Chronic dysglycemia has emerged as a significant modifier of COVID-19 outcomes, with elevated HbA1c levels potentially contributing to increased disease severity through mechanisms involving impaired immunity, endothelial dysfunction, and heightened inflammation. Understanding the prognostic value of HbA1c in hospitalized patients is essential for optimizing risk stratification and clinical management. Objective: To evaluate HbA1c levels and assess their association with clinical severity among hospitalized COVID-19 patients at the University of Lahore Teaching Hospital. Methods: A cross-sectional observational study was conducted among 70 adults with PCR-confirmed COVID-19. HbA1c was measured within 24 hours of admission, and patients were categorized into HbA1c < 7.0% and HbA1c ≥ 7.0%. Demographic, clinical, and laboratory data were collected, and disease severity was classified using national and WHO guidelines. Group comparisons and multivariable logistic regression were performed to determine the independent association between HbA1c and severe/critical illness. Results: Patients with HbA1c ≥ 7.0% exhibited higher inflammatory markers, lower admission oxygen saturation, and significantly greater frequencies of severe/critical disease (66.7% vs 37.5%), ICU admission (60.0% vs 30.0%), and mechanical ventilation (40.0% vs 17.5%). Elevated HbA1c independently predicted severe/critical COVID-19 (adjusted OR 2.78, 95% CI 1.10–7.01). Conclusion: Elevated HbA1c is strongly associated with increased COVID-19 severity and adverse in-hospital outcomes, underscoring the importance of early glycemic assessment in hospitalized patients.