López-Gómez Juan M, Villaverde Maite, Jofre Rosa, Rodriguez-Benítez Patrocinio, Pérez-García Rafael
Service of Nephrology, Hospital Gregorio Marañón, 28007 Madrid, Spain.
Kidney Int Suppl. 2005 Jan(93):S63-8. doi: 10.1111/j.1523-1755.2005.09314.x.
Excessive interdialytic weight gain (IDWG) is usually related to an overload of sodium and water, and is the most important factor for arterial hypertension in dialysis. On the other hand, food intake also contributes to IDWG, and is the basic factor for nutrition. The objective of this study is to assess the long-term prognostic effect of IDWG and its relationship with the nutritional status and blood pressure in patients in hemodialysis (HD).
We describe the results of a 5-year prospective observation study in which 134 HD patients were included (70 males and 64 females), with ages between 18 and 81. Initially, the average data were collected during 4 weeks, including total IDWG and percentages according to dry weight (IDWG%), nutritional parameters, and blood pressure. Patients were divided into 3 cohorts according to IDWG% (<2.9, 2.9-3.9, and >3.9%, respectively). Student t test, ANOVA, linear regression analysis, and Kaplan-Meier survival curves compared with log-rank test were used as statistical tools.
The mean IDWG% for the whole studied population was 3.5 +/- 1.1% (1.5-8.0%). It was not related to gender, but had an inverse correlation with age (P < 0.000) and serum bicarbonate level (P= 0.009). It was directly correlated with predialysis systolic and diastolic blood pressure, nPCR, urea and creatinine levels (P < 0.01 for all of them), and the body mass index (P < 0.000). Serum levels of albumin (44.7 +/- 4.0 g/dL) and prealbumin (31.9 +/- 7.4 mg/dL) had a direct correlation with total IDWG (P < 0.01). We found no significant relationship between or IDWG% and ferritin and transferrin levels. Five-year actuarial survival was 0.38, 0.52, and 0.63, respectively, in the 3 cohorts for IDWG% (P < 0.01).
Our results show that a greater IDWG is directly associated with a better nutritional status, although it is also associated with higher predialysis blood pressure. The greater the IDWG%, the better the long-term prognosis of the patients. The beneficial effects of IDWG on the nutritional status and prognosis are greater than the negative aspects that depend on its effects on blood pressure. One must distinguish clearly between some isolated instances of not complying with a diet from those situations where a higher IDWG is merely a reflection of a good nutritional status, and one must be careful so that dietary recommendations will not have a negative influence on nutritional aspects. One must watch and correct the trend towards higher acidosis in patients with a greater IDWG.
透析间期体重过度增加（IDWG）通常与钠和水负荷过重有关，是透析患者动脉高血压的最重要因素。另一方面，食物摄入也会导致IDWG增加，并且是营养的基本因素。本研究的目的是评估IDWG对血液透析（HD）患者的长期预后影响及其与营养状况和血压的关系。
我们描述了一项为期5年的前瞻性观察研究结果，该研究纳入了134例HD患者（70例男性和64例女性），年龄在18至81岁之间。最初，在4周内收集平均数据，包括总IDWG及其占干体重的百分比（IDWG%）、营养参数和血压。根据IDWG%（分别为<2.9%、2.9 - 3.9%和>3.9%）将患者分为3组。使用学生t检验、方差分析、线性回归分析以及与对数秩检验比较的Kaplan-Meier生存曲线作为统计工具。
整个研究人群的平均IDWG%为3.5±1.1%（1.5 - 8.0%）。它与性别无关，但与年龄呈负相关（P < 0.000）和血清碳酸氢盐水平呈负相关（P = 0.009）。它与透析前收缩压和舒张压、nPCR、尿素和肌酐水平直接相关（所有P值均<0.01），与体重指数也直接相关（P < 0.000）。血清白蛋白水平（44.7±4.0 g/dL）和前白蛋白水平（31.9±7.4 mg/dL）与总IDWG直接相关（P < 0.01）。我们发现IDWG%与铁蛋白和转铁蛋白水平之间无显著关系。IDWG%的3组患者5年精算生存率分别为0.38、0.52和0.63（P < 0.01）。
我们的结果表明，较高的IDWG与较好的营养状况直接相关，尽管它也与较高的透析前血压相关。IDWG%越高，患者的长期预后越好。IDWG对营养状况和预后的有益影响大于其对血压影响所带来的负面影响。必须清楚区分一些不遵守饮食规定的个别情况与IDWG较高仅仅反映良好营养状况的情况，并且必须谨慎行事，以免饮食建议对营养方面产生负面影响。必须关注并纠正IDWG较高患者酸中毒加重的趋势。
