Supplementary Material for: Association between Transfusion Status and Overall Survival in Patients with Myelodysplastic Syndromes: A Systematic Literature Review and Meta-Analysis

Introduction: Multiple studies show that transfusion independence (TI) in myelodysplastic syndrome (MDS) has a positive impact on overall survival (OS). To assess this, a systematic review and meta-analysis of the association between TI and OS in patients with MDS was conducted (PROSPERO ID: CRD42014007264). Methods: Comprehensive searches of 5 key bibliographic databases were conducted and supplemented with additional search techniques. Included were studies that had recruited adults aged >18 years with MDS and had examined the impact of transfusion status on OS. Results: Fifty-five studies (89 citations) were included. The vast majority reported a statistically significant hazard ratio (HR) for OS in favor of TI patients or in patients who acquired TI after treatment. A random-effects meta-analysis was conducted. Patients classed as TI at baseline showed a 59% decrease in the risk of death compared with transfusion-dependent (TD) patients [HR 0.41; 95% credible interval (CrI) 0.29-0.56], and this effect did not appear to interact significantly with illness severity (interaction coefficient HR 1.38; 95% CrI 0.62-3.41). A meta-analysis of studies where patients acquired TI was not possible, but those studies consistently reported a survival benefit for those who acquired TI. Conclusion: The findings revealed a 59% pooled reduction in mortality among TI patients when compared with TD patients.