Austen S K, Coombes J S, Fassett R G
School of Human Movement Studies, University of Queensland, St. Lucia, Queensland, Australia.
Clin Nephrol. 2003 Dec;60(6):375-85. doi: 10.5414/cnp60375.
Hyperhomocysteinemia is a potential risk factor for vascular disease and is associated with endothelial dysfunction, a predictor of adverse cardiovascular events. Renal patients (end-stage renal failure (ESRF) and transplant recipients (RTR)) exhibit both hyperhomocysteinemia and endothelial dysfunction with increasing evidence of a causative link between the 2 conditions. The elevated homocysteine appears to be due to altered metabolism in the kidney (intra-renal) and in the uremic circulation (extra-renal). This review will discuss 18 supplementation studies conducted in ESRF and 6 in RTR investigating the effects of nutritional therapy to lower homocysteine. The clinical significance of lowering homocysteine in renal patients will be discussed with data on the effects of B vitamin supplementation on cardiovascular outcomes such as endothelial function presented. Folic acid is the most effective nutritional therapy to lower homocysteine. In ESRF patients, supplementation with folic acid over a wide dose range (2 - 20 mg/day) either individually or in combination with other B vitamins will decrease but not normalize homocysteine. In contrast, in RTR similar doses of folic acid normalizes homocysteine. Folic acid improves endothelial function in ESRF patients, however this has yet to be investigated in RTR. Homocysteine-lowering therapy is more effective in ESRF patients than RTR.
高同型半胱氨酸血症是血管疾病的一个潜在危险因素，与内皮功能障碍相关，而内皮功能障碍是不良心血管事件的一个预测指标。肾病患者（终末期肾衰竭（ESRF）患者和肾移植受者（RTR））既存在高同型半胱氨酸血症，又有内皮功能障碍，越来越多的证据表明这两种情况之间存在因果联系。同型半胱氨酸升高似乎是由于肾脏内（肾内）和尿毒症循环中（肾外）代谢改变所致。本综述将讨论针对ESRF患者开展的18项补充治疗研究以及针对RTR患者开展的6项补充治疗研究，这些研究调查了营养疗法降低同型半胱氨酸的效果。将结合维生素B补充剂对心血管结局（如内皮功能）影响的数据，讨论降低肾患者同型半胱氨酸的临床意义。叶酸是降低同型半胱氨酸最有效的营养疗法。在ESRF患者中，单独或与其他B族维生素联合使用大剂量范围（2 - 20毫克/天）的叶酸会降低但不会使同型半胱氨酸恢复正常。相比之下，在RTR患者中，相似剂量的叶酸可使同型半胱氨酸恢复正常。叶酸可改善ESRF患者的内皮功能，然而在RTR患者中尚未对此进行研究。降低同型半胱氨酸的治疗在ESRF患者中比在RTR患者中更有效。
