School of Medicine, University of California San Francisco, 533 Parnassus Avenue, U404, Box 0532, San Francisco, CA, 94143-0532, USA.
Department of Pediatrics, Division of Pediatric Nephrology, Cincinnati Children's Hospital, Cincinnati, OH, USA.
Pediatr Nephrol. 2019 Sep;34(9):1557-1563. doi: 10.1007/s00467-019-04249-z. Epub 2019 Apr 8.
Few studies have examined how changes in BMI [body mass index] over time associate with risk of adverse outcomes in children receiving renal replacement therapy [RRT]. The objective of this study was to examine the association between annualized changes in BMI and the risk of death in children treated with RRT.
We performed a retrospective cohort study of 1182 pediatric dialysis and transplant patients in the Pediatric Growth and Development Special Study of the United States Renal Data System. Quintiles of annualized change in BMI z-score (with cutoffs of - 0.50, - 0.13, 0.09, 0.57) were used as the primary predictor, with the middle quintile (- 0.13 to 0.09) serving as the reference category. Cox models were used to examine the association between exposure and death, with time of analysis starting from the second BMI measurement.
Median follow-up time to death or censoring was 6 years. Median age was 14.6 years, and 61% of children had a functional graft at cohort entry. There was a U-shaped association between BMI change and mortality risk: a large decline in annualized BMI z-score change (> - 0.50) was associated with an increased risk of death (adjusted hazard ratio [aHR] 1.54 (95% CI 1.17-2.03), p = 0.002). A large increase in annualized BMI z-score change (> 0.57) was also associated with an increased risk of death (aHR 1.44 (95% CI 1.07-1.92), p = 0.02). No interaction was noted between annualized BMI change and initial treatment modality (dialysis or transplant, p = 0.15).
Maintenance of a stable BMI in pediatric patients receiving RRT may be associated with improved survival.
很少有研究探讨随着时间的推移 BMI（体重指数）的变化如何与接受肾脏替代治疗（RRT）的儿童不良结局的风险相关。本研究的目的是检验 BMI 年增长率与接受 RRT 治疗的儿童死亡风险之间的关系。
我们对美国肾脏数据系统儿科生长与发育特殊研究中的 1182 名儿科透析和移植患者进行了回顾性队列研究。将 BMI z 分数年增长率的五分位数（切点为-0.50、-0.13、0.09、0.57）作为主要预测因子，中间五分位数（-0.13 至 0.09）作为参考类别。Cox 模型用于检验暴露与死亡之间的关系，分析时间从第二次 BMI 测量开始。
中位随访时间到死亡或删失为 6 年。中位年龄为 14.6 岁，61%的患儿在入组时具有功能移植物。BMI 变化与死亡率风险之间存在 U 型关系：年增长率的大幅下降（> -0.50）与死亡风险增加相关（调整后的危险比[aHR]1.54[95%CI1.17-2.03]，p=0.002）。年增长率的大幅增加（>0.57）也与死亡风险增加相关（aHR 1.44[95%CI1.07-1.92]，p=0.02）。未观察到年增长率与初始治疗方式（透析或移植）之间的交互作用（p=0.15）。
在接受 RRT 的儿科患者中维持稳定的 BMI 可能与改善生存率相关。
