Suliman M E, Qureshi A R, Bárány P, Stenvinkel P, Filho J C, Anderstam B, Heimbürger O, Lindholm B, Bergström J
Divisions of Baxter Novum and Renal Medicine, Department of Clinical Science, Karolinska Institutet, Huddinge University Hospital, Stockholm, Sweden.
Kidney Int. 2000 Apr;57(4):1727-35. doi: 10.1046/j.1523-1755.2000.00018.x.
Hyperhomocysteinemia, cardiovascular disease (CVD), and malnutrition are common in patients with end-stage renal disease (ESRD). This study was designed to assess possible relationships between total plasma homocysteine (tHcy), nutritional status, and ischemic CVD.
We performed a cross-sectional study in 117 unselected patients on maintenance hemodialysis (HD) treatment, among whom there was a high prevalence of malnutrition (56%), as assessed by the subjective global nutritional assessment (SGNA), and a high prevalence of CVD (60%), and prospectively, we followed-up the overall mortality for four years.
The level of tHcy was elevated in 95% of the HD patients, and that of total plasma cysteine (tCys) was also significantly elevated, while the plasma concentrations of methionine (Met), serine (Ser), and taurine (Tau) were significantly lower than those in healthy controls. The 65 patients who were malnourished according to the SGNA score had significantly lower levels of serum albumin (SAlb), plasma IFG-1 (p-IGF-1), tHcy, tCys, and Met than the 52 patients with normal nutritional status, whereas the levels of Ser, Tau, plasma folate, and vitamin B12 were similar in the two groups. The prevalence of malnutrition was 30% in the 47 patients without CVD and was significantly higher (70%, P < 0.001) in the 70 patients with CVD, who also had lower tHcy, SAlb, plasma IGF-1, serum creatinine (SCr), and blood hemoglobin. The tHcy levels were positively correlated with SAlb, Met, tCys, and SCr. Stepwise, multiple-regression analysis showed that tCys, SAlb, and normalized protein equivalent of nitrogen appearance (nPNA), an indicator of protein intake, were independent predictors of tHcy. The patients with tHcy <24 micromol/L (median value) had a significantly worse four-year survival than those with a higher tHcy (> or =24 micromol/L).
Our results demonstrate that most of HD patients have grossly elevated tHcy levels, but that the absolute level appears to be dependent on nutritional status, protein intake, and SAlb. The results also suggest that the lower tHcy levels in patients with CVD than in those without CVD may be related to the higher prevalence of malnutrition and hypoalbuminemia in the CVD patients. This is also in accordance with our observation that the patients with lower tHcy had a worse survival rate than those with higher tHcy, considering that malnutrition is a strong risk factor for mortality and that CVD is the most common cause of death in ESRD patients.
高同型半胱氨酸血症、心血管疾病（CVD）和营养不良在终末期肾病（ESRD）患者中很常见。本研究旨在评估血浆总同型半胱氨酸（tHcy）、营养状况和缺血性CVD之间可能存在的关系。
我们对117例未经挑选的维持性血液透析（HD）患者进行了一项横断面研究，通过主观全面营养评估（SGNA）评估发现其中营养不良患病率很高（56%），CVD患病率也很高（60%），并且我们对总体死亡率进行了为期四年的前瞻性随访。
95%的HD患者tHcy水平升高，血浆总半胱氨酸（tCys）水平也显著升高，而甲硫氨酸（Met）、丝氨酸（Ser）和牛磺酸（Tau）的血浆浓度显著低于健康对照组。根据SGNA评分，65例营养不良患者的血清白蛋白（SAlb）、血浆胰岛素样生长因子-1（p-IGF-1）、tHcy、tCys和Met水平显著低于52例营养状况正常的患者，而两组患者的Ser、Tau、血浆叶酸和维生素B12水平相似。47例无CVD患者的营养不良患病率为30%，而70例CVD患者的营养不良患病率显著更高（70%，P<0.001），CVD患者的tHcy、SAlb、血浆IGF-1、血清肌酐（SCr）和血红蛋白水平也较低。tHcy水平与SAlb、Met、tCys和SCr呈正相关。逐步多元回归分析表明，tCys、SAlb和蛋白质摄入指标标准化氮呈现蛋白当量（nPNA）是tHcy的独立预测因素。tHcy<24微摩尔/升（中位数）的患者四年生存率明显低于tHcy较高（≥24微摩尔/升）的患者。
我们的结果表明，大多数HD患者的tHcy水平大幅升高，但绝对水平似乎取决于营养状况、蛋白质摄入量和SAlb。结果还表明，CVD患者的tHcy水平低于无CVD患者可能与CVD患者中更高的营养不良和低白蛋白血症患病率有关。这也与我们的观察结果一致，即tHcy较低的患者生存率比tHcy较高的患者更差，因为营养不良是死亡的一个强风险因素，且CVD是ESRD患者最常见的死亡原因。
