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.

引言：多项研究表明，骨髓增生异常综合征（myelodysplastic syndrome, MDS）患者的输血独立（transfusion independence, TI）状态对其总生存期（overall survival, OS）具有积极影响。为验证这一结论，本研究针对MDS患者的TI状态与OS之间的关联开展了系统评价与荟萃分析（PROSPERO ID: CRD42014007264）。
方法：研究对5个关键书目数据库进行了全面检索，并辅以补充检索手段。纳入研究需满足以下条件：招募年龄＞18岁的成人MDS患者，且分析了输血状态对OS的影响。
结果：最终纳入55项研究（共计89篇引文）。绝大多数研究均报告了具有统计学意义的风险比（hazard ratio, HR），证实TI患者或治疗后获得TI的患者总生存期更优。本研究开展随机效应荟萃分析：基线状态即为TI的患者，其死亡风险较输血依赖（transfusion-dependent, TD）患者降低59%[HR=0.41；95%可信区间（credible interval, CrI）0.29~0.56]，且该效应与疾病严重程度未呈现显著交互作用（交互系数HR=1.38；95% CrI 0.62~3.41）。针对治疗后获得TI的患者的荟萃分析未能实施，但相关研究均一致报告了获得TI的患者可获得生存获益。
结论：本研究结果显示，与TD患者相比，TI患者的合并死亡风险降低59%。