Department of nephrology, Yonsei University Wonju College of Medicine, Wonju, Kang-won, Korea.
Department of Biochemistry and Institute of Basic Medical Science, Yonsei University Wonju College of Medicine, Wonju, Kang-won, Korea.
PLoS One. 2018 Aug 8;13(8):e0202055. doi: 10.1371/journal.pone.0202055. eCollection 2018.
Malnutrition is very complex in patients with end-stage renal disease (ESRD) and is associated with poor prognosis. This is because hemodynamic changes, hormonal changes, persistent inflammatory reactions, and fluid overloads are more complicated as uremia is worsening. Bio-impedance spectroscopy (BIS) is a useful method to estimate fluid balance (Overhydration/ extracellular water, OH/ECW) and nutritional status (Phase angle, PhA). We aimed to evaluate the volume and nutritional status by BIS and to investigate the relationship between the appetite regulating hormones and the parameters of BIS in patients with stage 5 chronic kidney disease not undergoing dialysis (CKD5-ND).
We enrolled a total of 91 CKD5-ND patients. We measured routine serum markers including albumin and NT-proBNP and the appetite regulating hormones, leptin and ghrelin. We defined poor nutritional status as a PhA < 4.5°, and proper nutritional status as a PhA ≥ 4.5°. We also evaluated each patient's nutritional status by assessing their geriatric nutritional risk index (GNRI) and their volume status by measuring NT-proBNP.
Forty-one patients (45%) had poor nutritional status. Patients with a poor nutritional status had significantly higher OH/ECW (29.6 ± 12.7% vs. 6.2 ± 10.3%, p<0.001) and lower levels of leptin (3.8 ± 3.1 vs. 7.0 ± 6.2 ng/mL, p = 0.004) than those with proper nutritional status. PhA was associated with GNRI (r = 0.597, P<0.001) and NT-proBNP was associated with OH/ECW (r = 0.384, P<0.001). Leptin was negatively correlated with OH/ECW (r = -0.288, p = 0.006). In contrast, leptin was positively correlated with PhA (r = 0.263, p = 0.012). In multivariate logistic regression, high level of leptin (OR 7.00, 95% CI 1.74-28.10) was associated with proper nutrition, while an increased OH/ECW (OR 0.65, 95% CI 0.51-0.84) was associated with poor nutrition.
Our study demonstrates that CKD5-ND patients with poor nutrition generally also suffer from excessive body fluid. Low leptin level suggests poor nutrition in CKD5-ND patients. PhA could be used as a nutritional index for ESRD patients.
终末期肾病（ESRD）患者的营养不良非常复杂，与不良预后相关。这是因为随着尿毒症的恶化，血液动力学变化、激素变化、持续的炎症反应和体液超负荷变得更加复杂。生物阻抗谱（BIS）是一种有用的方法，可用于估计液体平衡（超水量/细胞外液，OH/ECW）和营养状况（相位角，PhA）。我们旨在通过 BIS 评估容量和营养状况，并研究食欲调节激素与 5 期慢性肾脏病未透析患者（CKD5-ND）的 BIS 参数之间的关系。
我们共纳入了 91 名 CKD5-ND 患者。我们测量了常规血清标志物，包括白蛋白和 NT-proBNP 以及食欲调节激素，瘦素和 ghrelin。我们将 PhA<4.5°定义为营养不良，PhA≥4.5°定义为营养状况良好。我们还通过评估患者的老年营养风险指数（GNRI）和测量 NT-proBNP 来评估每个患者的容量状态。
41 名患者（45%）存在营养不良。营养状况差的患者 OH/ECW 明显更高（29.6±12.7%比 6.2±10.3%，p<0.001），瘦素水平明显更低（3.8±3.1 比 7.0±6.2ng/mL，p=0.004）。PhA 与 GNRI 相关（r=0.597，P<0.001），NT-proBNP 与 OH/ECW 相关（r=0.384，P<0.001）。瘦素与 OH/ECW 呈负相关（r=-0.288，p=0.006）。相反，瘦素与 PhA 呈正相关（r=0.263，p=0.012）。在多元逻辑回归中，高水平的瘦素（OR 7.00，95%CI 1.74-28.10）与营养良好相关，而 OH/ECW 增加（OR 0.65，95%CI 0.51-0.84）与营养不良相关。
我们的研究表明，营养状况差的 CKD5-ND 患者通常也存在过多的体液。低瘦素水平提示 CKD5-ND 患者存在营养不良。PhA 可作为 ESRD 患者的营养指标。
