老年肾功能不全患者血浆同型半胱氨酸水平及其影响因素

目的研究老年肾功能不全（CRF）患者血浆同型半胱氨酸（Hcy）水平及其影响因素。方法采用快速高压液相层析法测定82例老年CRF患者和40例正常人的Hcy水平,同时用离子夺获分析法和微离子酶免疫分析法分别检测血浆叶酸（FA）和维生素B12（VitB12）水平。结果CRF患者高Hcy血症（HHcy）发生率高达86.6%,为正常对照组的34.6倍（P〈0.01）;且血浆Hcy的浓度随着血肌酐浓度的升高或内生肌酐清除率（Ccr）的降低而升高,有明显的相关性（P〈0.01）。CRF患者的血浆FA和VitB12与正常对照组均无明显差别,血浆tHcy水平与血浆FA浓度均呈负相关关系。血液透析后血浆Hcy水平较血液透析前下降约36%,但仍显著高于正常对照组（P〈0.01）。透析后20 h回复到透析前水平的76.6%～87.3%,在采用血仿膜和聚砜膜透析的患者之间,血浆tHcy水平无明显差异。结论老年CRF患者普遍存在HHcy血症,并且肾功能损害的程度与Hcy浓度明显相关,但没有明显的FA和VitB12缺乏,CRF时肾脏损害削弱了对Hcy的代谢或清除能力,可能是CRF患者血浆tHcy水平增高的主要原因。

Hyperhomocysteinema level in elderly patients with chronic renal failure and its influencing factors

Objective To study the hyperhomocysteinema level in elderly patients with chronic renal failure(CRF) and its influencing factors.Methods Plasma Hcy levels in 82 elderly patients with various degrees of CRF and 40 healthy controls were measured by rapid microcolumn high pressure liquid chromatography.The level of folic acid(FA) was determined by ion capture assay,and the level of cyanocobalamin(VB12) determined by microparticle enzyme immunoassay.Results The incidence of hyperhomocysteinemia in the patients with CRF was 86.6%,which was 34.6 times of that in healthy individuals(P<0.01).Linear regression analysis showed a significant correlation between plasma Hcy and creatinine concentration(r=0.368,P<0.01)or creatinine clearance(r=-0.357,P<0.01).Whereas,there was no significant difference in the levels FA and VB12 between the elderly patients with CRF and the healthy controls.The level of tHcy was negatively correlated with the level of FA in all subjects.The post-hemodialysis plasma Hcy levels decreased by 36%,and was significantly higher than that of healthy controls(P<0.01).The plasma Hcy level returned to 76.6%~87.3% of pre-hemodialysis level 20 hours after hemodialysis.There was no difference in clearance of tHcy between hemophan and polysulfone dialyzer.Conclusions Hyperhomocysteinemia is common in the elderly patients with various degrees of CRF.Plasma Hcy concentration in CRF is significantly related to the degree of renal failure.But the level of FA and VB12 are normal.It is considered that the renal dysfunction in elderly patients with CRF results in damage to clearance,which may be one cause of tHcy elevation in elderly patients with CRF.