Supplementary Material for: Dialysis Access as an Area of Improvement in Elderly Incident Hemodialysis Patients: Results from a Cohort Study from the International Monitoring Dialysis Outcomes Initiative

<b><i>Background:</i></b> Commencing hemodialysis (HD) using a catheter is associated with a higher risk of adverse outcomes, and early conversion from central-venous catheter (CVC) to arteriovenous fistula/graft (non-CVC) improves outcomes. We investigated CVC prevalence and conversion, and their effects on outcomes during the first year of HD in a multinational cohort of elderly patients. <b><i>Methods:</i></b> Patients ≥70 years from the MONDO Initiative who commenced HD between 2000 and 2010 in Asia-Pacific, Europe, North-, and South-America and survived at least 6 months were included in this investigation. We stratified by age (70-79 years [younger] vs. ≥80 years [older]) and compared access types (at first and last available date) and their changes. We studied the association between access at initiation and conversion, respectively, and all-cause mortality using Kaplan-Meier curve and Cox regression, and predicted the absence of conversion from catheter to non-CVC using adjusted logistic regression. <b><i>Results:</i></b> In 14,966 elderly, incident HD patients, survival was significantly worse when using a CVC at all times. In Europe, the conversion frequency from CVC to non-CVC was higher in the younger fraction. Conversion from non-CVC to CVC was associated with worsened outcomes only in the older fraction. <b><i>Conclusion:</i></b> These results corroborate the need for early HD preparation in the elderly HD population. Treatment of elderly patients who commence HD with a CVC should be planned considering aspects of individual clinical risk assessment. Differences in treatment practices in predialysis care specific to the elderly as a population may influence access care and conversion rate.

**研究背景：** 经导管启动血液透析（hemodialysis, HD）与不良结局风险升高相关，而早期将中心静脉导管（central-venous catheter, CVC）转换为动静脉瘘/移植物（arteriovenous fistula/graft，非CVC通路）可改善患者结局。本研究针对多国家老年患者队列，调查了HD启动首年的CVC使用率、通路转换情况及其对结局的影响。
**研究方法：** 本研究纳入了MONDO研究计划中2000至2010年间于亚太、欧洲、北美及南美地区启动HD，且年龄≥70岁、生存时长至少6个月的患者。研究按年龄分层：70~79岁组（较年轻组）与≥80岁组（高龄组），并对比了患者首次及末次随访时的血管通路类型及其变化情况。本研究分别采用Kaplan-Meier曲线（Kaplan-Meier curve）与Cox回归（Cox regression）分析，探讨了HD启动时的通路类型、通路转换与全因死亡率之间的关联；并通过校正后logistic回归（adjusted logistic regression）模型，预测了未从导管通路转换为非CVC通路的概率。
**研究结果：** 在14966例新发HD老年患者中，全程使用CVC通路的患者生存率显著更低。在欧洲地区，较年轻组患者的CVC向非CVC通路转换率更高。仅在高龄组中，从非CVC通路转换为CVC通路与不良结局升高相关。
**研究结论：** 本研究结果证实，老年HD患者需尽早开展透析前准备工作。对于经导管启动HD的老年患者，其治疗方案的制定应结合个体临床风险评估进行考量。针对老年群体的透析前治疗模式差异，可能会对血管通路护理及通路转换率产生影响。