Predictive value of HbA1c for in-hospital adverse prognosis in COVID-19: a systematic review and meta-analysis

Zhu, Zheng; Mao, Yaqian; Chen, Gang

Background and aims Clinical and laboratory predictors of adverse clinical course and death in COVID-19 patients urgently need to be identified. So far, the association between HbA1c and in-hospital mortality of COVID-19 remains a controversial issue. The aim of this study is to analyze predictive value of HbA1c for adverse prognosis in COVID-19. Methods Both Chinese and English databases were systematically searched using specific keywords associated with the aims until November 21th, 2020. The Newcastle-Ottawa Scale (NOS) was used for quality assessment. A Statistical analysis was carried out using Review Manager 5.3 and STATA 15.1. Results Nine clinical trials were included in this study involving 2577 subjects. The results indicate that the association between elevated HbA1c referred as a continuous variable and adverse prognosis of COVID-19 was not significant (OR, 1.02; 95%CI, 0.95-1.09). However, higher HbA1c levels regarded as a dichotomous variable contributed to an increase mortality of COVID-19 (OR, 2.300; 95%CI, 1.679-3.150). Results were stable in a sensitivity analysis. More studies are needed to demonstrate the effect of HbA1c on hospital mortality. Conclusion Prolonged uncontrolled hyperglycemia increases the risk of adverse prognosis in COVID-19. Patients with higher HbA1c should be monitored strictly to minimize the risk of adverse prognosis in COVID-19.