Post-acute metabolic changes and risk of new-onset diabetes following COVID-19: a systematic review and meta-analysis

Background: COVID-19 has been associated with persistent metabolic disturbances; however, the magnitude, consistency, and underlying mechanisms of post-infection alterations in glucose regulation remain incompletely characterized. Methods: We conducted a systematic review and meta-analysis in accordance with PRISMA guidelines. PubMed and Embase were searched on December 18, 2024, for studies published from 2020 onward. Eligible studies included observational cohort and cross-sectional designs assessing metabolic outcomes at least three months after recovery from COVID-19. Results: Sixteen studies met inclusion criteria. Pooled analysis suggested a 41% increased risk of new-onset diabetes among COVID-19 survivors compared with non-infected individuals (RR 1.41, 95% CI: 1.38-1.44); however, this estimate was predominantly driven by a single large-scale study. Quantitative synthesis demonstrated higher HbA1c (SMD 1.44, 95% CI: 0.36-2.52) and Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) (SMD 0.96, 95% CI: 0.33-1.58), consistent with impaired glycemic control and increased insulin resistance. In contrast, fasting blood glucose (FBG) findings were inconsistent and highly heterogeneous (SMD 0.77, 95% CI: -0.40-1.94). Substantial heterogeneity was observed across outcomes. Conclusion: COVID-19 may be associated with an increased risk of incident diabetes and persistent metabolic dysregulation. However, the limited number of studies contributing to pooled risk estimates and the influence of large registry-based data warrant cautious interpretation. These findings support consideration of metabolic monitoring and longitudinal follow-up in post-COVID care, particularly among individuals at elevated cardiometabolic risk. Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42025630971.