Prevalence of protein-energy wasting (PEW) and evaluation of diagnostic criteria in Japanese maintenance hemodialysis patients

Background and Objectives: The International Society of Renal Nutrition and Metabolism (ISRNM) has recently recommended the use of the term “protein-energy wasting” (PEW). PEW is a state of malnutrition with decreased body stores of protein and energy fuel in hemodialysis patients and is known as a risk factor for morbidity and mortality. We examined the prevalence of PEW and the characteristics of PEW patients in a hemodialysis center in Japan. Methods and Study Design: Fifty-nine outpatients undergoing maintenance hemodialysis at Iga City General Hospital were evaluated. We observed their biochemical data, body composition, dietary intake, and the number of steps prospectively. PEW was defined according to ISRNM criteria. Results: Nine patients (15% of total) were diagnosed as having PEW. Among indicators of PEW criteria, the relevance ratios of “reduced muscle mass” and “unintentional low dietary energy intake” were significantly higher in PEW than in non-PEW. The number of steps was lower, and serum levels of glucose and C-reactive protein were higher in PEW. Conclusion: About 15% of Japanese hemodialysis patients are estimated to have PEW. Our results suggested that major contributing factors to PEW were reduced muscle mass, unintentional low dietary energy intake, lower amount of exercise, insulin resistance, and chronic inflammation.

背景与目的：国际肾营养与代谢协会（ISRNM）最近推荐使用术语“蛋白质能量消耗（PEW）”。PEW 是血液透析患者体内蛋白质和能量储存减少的一种营养不良状态，并且被认为是患病率和死亡率的危险因素。我们在日本的一个血液透析中心研究了PEW 的患病率和PEW 患者的特征。方法与研究设计：我们评估了58 名在伊贺市综合医院做维持性血液透析的门诊患者，并观察了他们的生化数据、体成分、膳食摄入量和行走的步数。根据ISRNM 标准诊断PEW。结果：9 名（占总数的15%）患者被诊断为PEW。在PEW 诊断标准指标中，PEW 患者“肌肉量减少”和“无意识的低膳食能量摄入”的比例高于非PEW 患者。PEW 患者中行走的步数较低，而血清葡萄糖和C-反应蛋白水平较高。结论：约有15%的日本血液透析患者患有PEW。我们的研究结果表明：引起PEW 的主要因素是肌肉量减少、无意识的低膳食能量摄入、运动量低、胰岛素抵抗和慢性炎症。