透析开始残余肾功能与维持性透析患者预后的关系

目的 评估终末期肾病患者透析开始残余肾功能与维持性透析预后的关系.方法 收集2005年1月1日至2009年9年30日新进入血透或腹透治疗的终末期肾病成年患者资料,随访至2010年3月31日.根据透析开始时估算肾小球滤过率(eGFR)分为≥10.5、8～＜10.5、6～＜8、＜6 ml· min-1·(1.73 m2)-1 4组.eGFR评估采用MDRD简化公式.终点事件为全因死亡和心脑血管死亡.结果 (1)共562例患者入选,透析开始中位eGFR为5.60(2.26～12.62) ml· min-1·(1.73 m2)-1;中位随访时间为17(0～58)个月 ;死亡141例,中位生存期为45.48(43.05 ～47.90)个月.随着透析开始eGFR下降,4组患者Scr、BUN、血尿酸(SUA)、血前白蛋白、血磷、血钙磷乘积、整段甲状旁腺激素(iPTH)、平均动脉压(MAP)逐渐升高 ;血红蛋白(Hb)、男性患者比例、并发糖尿病比例、Charison并发症指数≥5比例逐渐下降,差异均有统计学意义(均P＜ 0.05).随着透析开始eGFR下降,并发左室肥大比例有逐渐升高趋势,但差异无统计学意义.(2)Kaplan-Meier生存曲线显示4组患者总体生存率差异无统计学意义.Cox回归分析显示透析开始eGFR与透析预后无显著关系.对透析非早期(＞3个月)死亡患者进行Kaplan-Meier生存曲线分析,4组患者1年生存率差异无统计学意义.多因素Cox回归分析显示透析开始eGFR是透析1年生存预后的保护因素(HR =0.791,95％CI 0.669～0.935,P＜0.01).(3)以心脑血管死亡为终点事件,多因素Cox回归分析显示,透析开始eGFR是心脑血管生存预后(HR =0.868,95％CI 0.777～0.971,P＜0.05)和1年心脑血管生存预后(HR=0.937,95％CI 0.851～0.992,P＜0.05)的保护因素.(4)多因素Cox回归分析显示,透析开始eGFR增高1 ml·min-1·(1.73 m2)-1,腹膜透析患者死亡风险下降10％(HR=0.90,95％CI 0.81～0.99,P＜ 0.05).血液透析方式4组患者Kaplan-Meier生存率分析显示,差异有统计学意义(Log-rank检验,P=0.047),8～＜10.5组生存率最低,与6～＜8组、＜6组差异有统计学意义(Log-rank检验,P=0.033,P=0.005).多因素Cox回归分析并未显示透析开始eGFR与预后相关.多因素Cox回归分析提示透析开始eGFR增高1 ml·min-1·(1.73 m2)-1,慢性肾小球肾炎患者和慢性肾小球肾炎腹膜透析患者死亡风险分别降低16.6％(HR=0.834,95％CI 0.736～0.946,P＜0.01)和32.1％(HR=0.679,95％CI 0.535～0.862,P＜0.01).以心脑血管死亡为终点,多因素Cox回归分析显示透析开始eGFR增高1 ml·min-1·(1.73 m2)-1,慢性肾小球肾炎患者心脑血管死亡风险下降18.2％(HR=0.818,95％CI 0.669～0.999,P＜0.05).结论 本组患者透析时机明显晚于国际透析指南的标准.随着透析开始eGFR降低,并发症增多及程度加重.早期透析可能无法提高透析患者的总体生存率,但可能有助于改善患者心脑血管及1年总体生存预后和腹膜透析、慢性肾小球肾炎患者的预后.

Association of residual renal function at initiation of dialysis with prognosis in maintenance dialysis patients

Objective To examine the association between residual renal function at initiation of dialysis and prognosis in maintenance dialysis patients. Methods Incident patients with end-stage renal diseases initiating dialysis between 1 January 2005 and 30 September 2009, followed up to 31 March 2010 were enrolled in this study. Residual renal function was evaluated using eGFR estimated by the abbreviated MDRD equation. Patients were classified into four groups according to eGFR of ≥10.5, 8 to <10.5, 6 to <8, <6 ml?min-1?(1.73 m2)-1. The outcome was all-cause and cardiocerebral vascular mortality. Results (1) A total of 562 patients were included. The median eGFR at initiation of dialysis was 5.60 (2.26-12.62) ml?min-1?(1.73 m2)-1. The median follow-up time was 17 (0-58) months from initiation of dialysis and 141 patients died within this period. The median survival time was 45.48 (43.05-47.90) months. With eGFR declined, Scr, BUN, serum uric acid, serum prealbumin, phosphorus, calcium and phosphate product, iPTH, mean arterial pressure (MAP) at initiation of dialysis increased (P<0.05), and hemoglobin, proportion of male, proportion of diabetes comorbidity, proportion of the Charlson comorbidity index≥5 decreased (P<0.05). Though there was no significant difference among the four groups, the proportion of left ventricular hypertrophy comorbidity increased when eGFR declined. (2) There was no significant difference of all-cause mortality among four groups using Kaplan-Meire survival curve. Cox regression model indicated no significant difference of all-cause mortality in levels of eGFR (HR=1.012, 95%CI 0.961-1.065, P=0.654). Without patients died in the first 3 months, the multivariate Cox regression model indicated eGFR at initiation of dialysis was the protective factor to 1 year survival (HR=0.791, 95%CI 0.669-0.935, P<0.01). (3) The multivariate Cox regression model indicated the risk of overall and 1 year cardiocerebral vascular death decreased with eGFR at initiation of dialysis increased (HR=0.868, 95%CI 0.777-0.971, P<0.05; HR=0.937, 95%CI 0.851-0.992, P<0.05, respectively). (4) The multivariate Cox regression model indicated eGFR at initiation of dialysis was benefit to survival of patients treated by peritoneal dialysis, with all-cause death risk decreased by 10% when eGFR increased by 1 ml?min-1?(1.73 m2)-1 (HR=0.90, 95%CI 0.81-0.99, P<0.05). In hemodialysis patients, Kaplan-Meire survival curve was significantly different among the four groups (Log-rank test, P=0.047); the survival of the group of 8 to <10.5 ml?min-1?(1.73 m2)-1 was lower as compared to the groups of 6 to <8 (Log-rank test, P=0.033) and <6 ml?min-1?(1.73 m2)-1 (Log-rank test, P=0.005); but the multivariate Cox regression model indicated no relationship between survival and eGFR. In the subgroup of chronic glomerulonephritis as primary renal disease, the eGFR at initiation of dialysis was the benefit factor, with all-cause death risk decreased by 16.6% (HR=0.834, 95%CI 0.736-0.946, P<0.01) and cardiocerebral vascular death risk decreased by 18.2% (HR=0.818, 95%CI 0.669-0.999, P<0.05) when eGFR increased by 1 ml?min-1?(1.73 m2)-1. In the subgroup of chronic glomerulonephritis treated by peritoneal dialysis, the all-cause death risk decreased by 32.1% with eGFR increased by 1 ml?min-1?(1.73 m2)-1 (HR=0.679, 95%CI 0.535-0.862, P<0.01). Conclusions Early initiation of dialysis may not be associated with improved overall survival, but may reduce cardiocerebral vascular and 1 year all-cause mortality, improve the survival of chronic glomerulonephritis patients and peritoneal dialysis patients.