Glycosylated hemoglobin is associated with systemic inflammation, hypercoagulability, and prognosis of COVID-19 patients

BACKGROUND: Diabetes is a risk factor for the progression and prognosis of coronavirus disease (COVID-19), but the relationship between glycosylated hemoglobin (HbA1c) level, inflammation, and prognosis of COVID-19 patients has not been explored. METHODS: This was a retrospective study of COVID-19 patients who underwent an HbA1c test. Their demographic data, medical history, signs and symptoms of COVID-19, laboratory test results, and final outcomes of COVID-19 treatment were collected and analyzed. RESULTS: A total of 132 patients were included and divided into three groups based on their blood glucose status. There were significant differences in SaO(2), serum ferritin level, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), fibrinogen (Fbg) level, and IL6 level among the three groups. A pairwise comparison of the groups showed that groups B and C were significantly different from group A in terms of CRP, ESR, and Fbg, IL6, and serum ferritin levels (P < 0.05). Correlation analysis showed that there was a linear negative correlation between SaO(2) and HbA1c (r = −0.22, P = 0.01), while there was a linear positive correlation between serum ferritin, CRP, Fbg, and ESR levels and HbA1c (P < 0.05). CONCLUSIONS: High HbA1c level is associated with inflammation, hypercoagulability, and low SaO(2) in COVID-19 patients, and the mortality rate (27.7%) is higher in patients with diabetes. Determining HbA1c level after hospital admission is thus helpful assessing inflammation, hypercoagulability, and prognosis of COVID-19 patients.