Readmission in patients with hematologic malignancies: A systematic review and meta-analysis.

OBJECTIVE: This study was performed to quantify readmission rates across different follow-up time windows among patients with hematologic malignancies (HM) and to systematically evaluate associated influencing factors. METHODS: Eight databases were searched up to October 22, 2025. Studies reporting readmission rates in patients with HM were included. Methodological quality was assessed using the Joanna Briggs Institute Critical Appraisal Checklist. Meta-analysis was performed using R (version 4.5.2). Heterogeneity was explored through sensitivity and subgroup analyses. Publication bias was assessed using funnel plots and Egger's test. RESULTS: A total of 104 studies were included. Among HSCT recipients, the pooled readmission rates were 33.19% within 7 days, 23.93% within 30 days, 32.53% within 90 days, 36.23% within 100 days, 47.69% within 180 days, and 56.55% within one year. Among patients not undergoing HSCT, the corresponding rates were 21.54% within 30 days, 36.12% within 90 days, and 35.81% within 180 days. In the disease-specific analysis of 30-day readmission among patients not undergoing HSCT, the pooled rates were 22.20% for leukemia, 13.67% for lymphoma, and 26.67% for multiple myeloma, with no statistically significant subgroup difference (P = 0.458). Among HSCT recipients, readmission rates differed significantly by transplantation type at 30, 100, and 180 days and at one year (P = 0.033, 0.009, <0.0001, and <0.0001, respectively). CONCLUSION: Early readmissions may reflect acute treatment-related complications, whereas longer-term readmission patterns may additionally be influenced by transplant-related morbidity, patient characteristics, and healthcare-system factors.