Nerbass Fabiana Baggio, Draibe Sérgio Antônio, Feiten Simone Flach, Chiarello Paula Garcia, Vannucchi Hélio, Cuppari Lilian
Nutrition Program, Federal University of São Paulo, SP, Brazil.
J Am Diet Assoc. 2006 Feb;106(2):267-70. doi: 10.1016/j.jada.2005.10.035.
This cross-sectional study aimed to investigate the prevalence of hyperhomocysteinemia, the determinants of plasma total homocysteine concentrations, and the relationship of total homocysteine with nutritional parameters in a sample of patients with chronic kidney disease (CKD) and not yet on dialysis. The study was done with outpatients from the Nephrology Division of the Federal University of São Paulo and Oswaldo Ramos Foundation. Sixty-six patients with CKD (70% male; age 58.6+/-15.6 years [mean+/-standard deviation]) with moderate to severe renal impairment (creatinine clearance=29.8+/-14.3 mL/min [0.5+/-0.24 mL/sec]), clinically stable, and older than 18 years were included. A group of 20 healthy subjects from the clinic staff was also studied for reference values for plasma homocysteine, folate, and vitamin B-12 concentration. Fasting blood samples were collected to determine plasma total homocysteine, folate, vitamin B-12, and creatinine. To calculate creatinine clearance, a 24-hour urine collection sample was obtained. The assessment of nutritional status included anthropometric parameters. Pearson correlation, Mann-Whitney test, and multiple linear regression analysis were used for statistical analyses. The main results showed that the concentration of total homocysteine in the patients was significantly increased compared with the healthy subjects (3.4+/-1.7 vs 1.41+/-0.42 mg/L [25.4+/-12.2 vs 10.4+/-3.1 micromol/L]; P<0.001). Plasma folate and plasma vitamin B-12 were in the normal range and did not differ between patients and healthy individuals. A high prevalence of hyperhomocysteinemia (total homocysteine >1.89 mg/L [14 micromol/L]) was found in the patients (89%). Plasma total homocysteine did not correlate with any of the nutritional parameters studied and did not differ between patients in terms of whether they were using or not using folic acid supplementation (3.07+/-1.09 vs 3.55+/-1.78 mg/L [22.7+/-8.1 vs 26.3+/-13.2 micromol/L]; P=0.47), although plasma folate was significantly higher in the supplemented group (12.6+/-3.0 vs 8.0+/-3.6 ng/mL [28.5+/-6.8 nmol/L vs 18.1+/-8.2 nmol/L]; P<0.001). According to the multiple regression analysis, the determinants of total homocysteine were only plasma folate, plasma vitamin B-12, and creatinine clearance (r2=0.20). In conclusion, a high prevalence of hyperhomocysteinemia was found in our sample of nondialyzed patients with CKD. The determinants of total homocysteine levels were plasma folate, plasma vitamin B-12, and creatinine clearance. No association between nutritional parameters and total homocysteine was observed.
这项横断面研究旨在调查尚未接受透析的慢性肾脏病（CKD）患者样本中高同型半胱氨酸血症的患病率、血浆总同型半胱氨酸浓度的决定因素，以及总同型半胱氨酸与营养参数之间的关系。该研究对圣保罗联邦大学肾脏病科和奥斯瓦尔多·拉莫斯基金会的门诊患者进行。纳入了66例CKD患者（70%为男性；年龄58.6±15.6岁[平均值±标准差]），这些患者有中度至重度肾功能损害（肌酐清除率=29.8±14.3 mL/分钟[0.5±0.24 mL/秒]），临床稳定，年龄大于18岁。还对20名来自诊所工作人员的健康受试者进行了研究，以获取血浆同型半胱氨酸、叶酸和维生素B-12浓度的参考值。采集空腹血样以测定血浆总同型半胱氨酸、叶酸、维生素B-12和肌酐。为计算肌酐清除率，采集了24小时尿液样本。营养状况评估包括人体测量参数。采用Pearson相关性分析、Mann-Whitney检验和多元线性回归分析进行统计分析。主要结果显示，与健康受试者相比，患者的总同型半胱氨酸浓度显著升高（3.4±1.7 vs 1.41±0.42 mg/L[25.4±1
