Department of Rehabilitation Sciences, Kitasato University Graduate School of Medical Sciences, Kanagawa, Japan; Department of Epidemiology and Prevention, Center for Clinical Sciences, National Center for Global Health and Medicine, Tokyo, Japan.
Department of Physical Therapy, School of Rehabilitation, Hyogo University of Health Sciences, Hyogo, Japan.
J Ren Nutr. 2021 Jul;31(4):370-379. doi: 10.1053/j.jrn.2020.08.006. Epub 2020 Sep 18.
Sarcopenia (especially muscle mass assessed using gold standard techniques) has been suggested as a poorer predictor of mortality than muscle function in patients undergoing hemodialysis. Appropriate methods to estimate muscle mass for use as a good predictor of clinical outcomes remain to be established. We investigated whether the modified creatinine index (mCI), which is a surrogate marker of muscle mass, could predict mortality and cardiovascular (CV) hospitalizations independent of muscle function and other confounders in patients on hemodialysis.
In this retrospective study, outpatients (n = 542; mean age, 65.3 years; 60% men; median dialysis vintage, 29 months; mean BMI, 22.0 kg/m) undergoing hemodialysis were investigated. The mCI, handgrip strength, and gait speed were assessed and related to all-cause mortality and a composite of CV hospitalizations and all-cause mortality. Cox proportional and mixed-effects negative binomial models were fit for mortality and the composite outcomes.
Patients were followed up for a median 3 years (interquartile range: 1.5-5.7). Each per SD increase of mCI (HR:0.63, 95% CI:0.62-0.65), handgrip strength (HR:0.51, 95% CI:0.48-0.54), and gait speed (HR:0.60, 95% CI:0.56-0.64) were significantly associated with lower all-cause mortality rates after adjusting for covariates. The mCI was consistently found to be an independent predictor of mortality after additional adjustment for handgrip strength or gait speed. Furthermore, sarcopenic conditions [i.e., lower mCI, and lower handgrip strength (HR:3.79, 95% CI:2.09-6.87) or slower gait speed (HR:4.20, 95% CI:2.38-7.41)] were significantly associated with a higher risk of mortality after adjusting for covariates. Associations of mCI with multiple CV hospitalizations and mortality were similar to those between mCI and mortality.
The mCI was a good predictor of clinical outcomes and was comparable to muscle function, including handgrip strength and gait speed. The mCI is likely to provide additional diagnostic and prognostic values for sarcopenia in patients on hemodialysis.
在接受血液透析的患者中，肌少症（尤其是使用金标准技术评估的肌肉量）被认为比肌肉功能更能预测死亡率。仍然需要确定合适的方法来估计肌肉量，作为临床结果的良好预测指标。我们研究了改良肌酐指数（mCI）是否可以预测死亡率和心血管（CV）住院，而不受血液透析患者的肌肉功能和其他混杂因素的影响。
在这项回顾性研究中，调查了 542 名门诊患者（平均年龄 65.3 岁；60%为男性；中位透析龄 29 个月；平均 BMI 为 22.0kg/m²）。评估了 mCI、握力和步态速度，并将其与全因死亡率和 CV 住院和全因死亡率的复合结局相关联。使用 Cox 比例和混合效应负二项式模型对死亡率和复合结局进行拟合。
患者中位随访 3 年（四分位距：1.5-5.7）。在调整协变量后，mCI（HR：0.63，95%CI：0.62-0.65）、握力（HR：0.51，95%CI：0.48-0.54）和步态速度（HR：0.60，95%CI：0.56-0.64）每增加一个标准差，全因死亡率均显著降低。在进一步调整握力或步态速度后，mCI 仍然是死亡率的独立预测因素。此外，在调整协变量后，肌少症状态[即较低的 mCI 以及较低的握力（HR：3.79，95%CI：2.09-6.87）或较慢的步态速度（HR：4.20，95%CI：2.38-7.41）]与死亡率升高显著相关。mCI 与多次 CV 住院和死亡率的关联与 mCI 与死亡率的关联相似。
mCI 是临床结局的良好预测指标，与肌肉功能（包括握力和步态速度）相当。mCI 可能为血液透析患者的肌少症提供额外的诊断和预后价值。
