Division of Nephrology, Taipei Tzu Chi Hospital, Buddhist Tzu Chi Medical Foundation, and School of Medicine, Tzu Chi University, Hualien, Taiwan.
Division of Renal Medicine, Department of Internal Medicine, Tungs' Taichung MetroHarbor Hospital, Taichung, Taiwan.
Am J Clin Nutr. 2018 Apr 1;107(4):664-672. doi: 10.1093/ajcn/nqy006.
Normal-weight obesity (NWO), defined by a normal body mass index (BMI) and high body fat percentage, has been shown to be associated with cardiometabolic dysfunction and an increased risk of cardiovascular disease and mortality in the general population. However, little is known about the clinical implications of NWO among patients with chronic kidney disease (CKD).
The aim of this study was to assess the characteristics and outcomes of nondiabetic CKD patients with NWO.
A total of 178 nondiabetic patients with stages 3-5 CKD were prospectively followed for a median of 4.9 y. The patients were classified into 3 different adiposity phenotypes: nonobese [BMI (in kg/m2) <25 and fat mass percentage (FM%) ≤25% for men or ≤35% for women], NWO (BMI <25 and FM% >25% for men or >35% for women), and preobese-obese (BMI ≥25). FM% was determined using the Body Composition Monitor, a multifrequency bioimpedance spectroscopy device. The outcome was a composite of cardiovascular events or all-cause mortality.
The prevalence of NWO was 28.1% among nondiabetic CKD patients with a normal BMI. NWO patients were older, had lower lean body mass, and had higher plasma interleukin-6 concentrations than nonobese patients. However, homeostatic model assessment for insulin resistance levels did not differ between the 2 groups. NWO patients showed a significant 3-fold higher risk of the composite outcome (HR 2.96, 95% CI: 1.13, 7.77; P < 0.05) than did nonobese patients in the fully adjusted model. Preobese-obese patients were not at increased risk compared to nonobese patients.
NWO was associated with the worst prognosis among the 3 different adiposity phenotypes in nondiabetic CKD patients. Our findings suggest the importance of using direct measures of adiposity for risk assessment in CKD patients who are normal-weight. This trial was registered at clinicaltrials.gov as NCT03285074.
正常体重肥胖症（NWO）定义为身体质量指数（BMI）正常但体脂百分比高，已被证实与普通人群中的心脏代谢功能障碍以及心血管疾病和死亡率增加有关。然而，对于慢性肾脏病（CKD）患者中的 NWO，人们知之甚少。
本研究旨在评估非糖尿病 CKD 患者中 NWO 的特征和结局。
共有 178 名非糖尿病、CKD 3-5 期患者前瞻性随访中位数为 4.9 年。这些患者被分为 3 种不同的肥胖表型：非肥胖[BMI（kg/m2）<25 且体脂百分比（FM%）男性≤25%或女性≤35%]、NWO（BMI<25 且男性 FM%>25%或女性>35%）和超胖-肥胖[BMI≥25]。FM%使用身体成分监测仪（一种多频生物阻抗光谱设备）来确定。结局为心血管事件或全因死亡率的复合结果。
在 BMI 正常的非糖尿病 CKD 患者中，NWO 的患病率为 28.1%。NWO 患者年龄较大，瘦体重较低，白细胞介素-6 浓度较高，而两组间胰岛素抵抗的稳态模型评估值没有差异。在完全调整的模型中，NWO 患者发生复合结局的风险显著增加 3 倍（HR 2.96，95%CI：1.13，7.77；P<0.05）。与非肥胖患者相比，超胖-肥胖患者的风险没有增加。
在非糖尿病 CKD 患者的 3 种不同肥胖表型中，NWO 与最差的预后相关。我们的研究结果表明，在 BMI 正常的 CKD 患者中，使用直接的肥胖测量方法进行风险评估非常重要。本试验在 clinicaltrials.gov 注册为 NCT03285074。
