Marcelli Daniele, Usvyat Len A, Kotanko Peter, Bayh Inga, Canaud Bernard, Etter Michael, Gatti Emanuele, Grassmann Aileen, Wang Yuedong, Marelli Cristina, Scatizzi Laura, Stopper Andrea, van der Sande Frank M, Kooman Jeroen
Fresenius Medical Care, Bad Homburg, Germany;
Fresenius Medical Care, Waltham, Massachusetts;
Clin J Am Soc Nephrol. 2015 Jul 7;10(7):1192-200. doi: 10.2215/CJN.08550814. Epub 2015 Apr 21.
High body mass index appears protective in hemodialysis patients, but uncertainty prevails regarding which components of body composition, fat or lean body mass, are primarily associated with survival.
DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Data between April 2006 and December 2012 were extracted from the Fresenius Medical Care Europe subset of the international MONitoring Dialysis Outcomes initiative. Fresenius Medical Care Europe archives a unique repository of predialysis body composition measurements determined by multifrequency bioimpedance (BCM Body Composition Monitor). The BCM Body Composition Monitor reports lean tissue indices (LTIs) and fat tissue indices (FTIs), which are the respective tissue masses normalized to height squared, relative to an age- and sex-matched healthy population. The relationship between LTI and FTI and all-cause mortality was studied by Kaplan-Meier analysis, multivariate Cox regression, and smoothing spline ANOVA logistic regression.
In 37,345 hemodialysis patients, median (25th-75th percentile) LTI and FTI were 12.2 (10.3-14.5) and 9.8 (6.6-12.4) kg/m(2), respectively. Median (25th-75th percentile) follow-up time was 266 (132-379) days; 3458 (9.2%) patients died during follow-up. Mortality was lowest with both LTI and FTI in the 10th-90th percentile (reference group) and significantly higher at the lower LTI and FTI extreme (hazard ratio [HR], 3.37; 95% confidence interval [95% CI], 2.94 to 3.87; P<0.001). Survival was best with LTI between 15 and 20 kg/m(2) and FTI between 4 and 15 kg/m(2) (probability of death during follow-up: <5%). When taking the relation between both compartments into account, the interaction was significant (P=0.01). Higher FTI appeared protective in patients with low LTI (HR, 3.37; 95% CI, 2.94 to 3.87; P<0.001 at low LTI-low FTI, decreasing to HR, 1.79; 95% CI, 1.47 to 2.17; P<0.001 at low LTI-high FTI).
This large international study indicates best survival in patients with both LTI and FTI in the 10th-90th percentiles of a healthy population. In analyses of body composition, both lean tissue and fat tissue compartments and also their relationship should be considered.
高体重指数对血液透析患者似乎具有保护作用，但关于身体组成的哪些成分（脂肪或瘦体重）与生存率主要相关仍存在不确定性。
设计、地点、参与者与测量：2006年4月至2012年12月的数据取自国际透析结果监测计划的费森尤斯医疗欧洲子集。费森尤斯医疗欧洲保存了一个独特的透析前身体组成测量库，该测量由多频生物阻抗（BCM身体组成监测仪）确定。BCM身体组成监测仪报告瘦组织指数（LTI）和脂肪组织指数（FTI），它们是相对于年龄和性别匹配的健康人群，分别将组织质量除以身高的平方得到的。通过Kaplan-Meier分析、多变量Cox回归和平滑样条ANOVA逻辑回归研究LTI和FTI与全因死亡率之间的关系。
在37345例血液透析患者中，LTI和FTI的中位数（第25 - 75百分位数）分别为12.2（10.3 - 14.5）kg/m²和9.8（6.6 - 12.4）kg/m²。随访时间的中位数（第25 - 75百分位数）为266（132 - 379）天；3458例（9.2%）患者在随访期间死亡。LTI和FTI均处于第10 - 90百分位数（参考组）时死亡率最低，而在LTI和FTI极低水平时显著更高（风险比[HR]，3.37；95%置信区间[95%CI]，2.94至3.87；P<0.001）。LTI在15至20 kg/m²且FTI在4至15 kg/m²时生存率最佳（随访期间死亡概率：<5%）。考虑到两个部分之间的关系时，相互作用具有显著性（P = 0.01）。在LTI较低的患者中，较高的FTI似乎具有保护作用（HR，3.37；95%CI，2.94至3.87；低LTI - 低FTI时P<0.001，降至HR，1.79；95%CI，1.47至2.17；低LTI - 高FTI时P<0.001）。
这项大型国际研究表明，LTI和FTI均处于健康人群第10 - 90百分位数的患者生存率最佳。在身体组成分析中，应同时考虑瘦组织和脂肪组织部分及其关系。
