EFFECTS OF VITAMIN SUPPLEMENT ON PLASMA HOMOCYSTEINE AND APOLIPOPROTEIN A₁ LEVELS IN CHILDREN WITH NEPHROTIC SYNDROME IN IBADAN, NIGERIA

Abstract

Nephrotic Syndrome (NS), a condition characterized by proteinuria, hypoproteinaemia, and hypercholesterolaemia resulting from damage to the kidneys' glomeruli blood vessel, is a common childhood disease worldwide. Elevated Total Homocysteine (tHcy) has been proposed as a major contributor to morbidity and mortality in children with NS and lowering tHcy level may improve survival in children. Though childhood NS is prevalent in Nigeria, evidence of hyperhomocysteinaemia and the effects of vitamin supplementation on tHcy and lipids arc scanty. Therefore, this study was conducted to evaluate plasma tHcy, lipids and apolipoprotein-AI in NS before and after vitamin supplementation. Using a pre-post, quasi-experimental design, 84 children (42 with NS and 42 age-sex and matched controls) were consecutively recruited at the University College Hospital, Ibadan. A structured questionnaire was used to collect clinical and anthropometric data, Weight and height were measured using a weighing scale and stadiometer. All children with NS were given 5 mg folate and one tablet of vitamin-B-complex daily. Blood samples collected at baseline and 3-month post supplementation, were analysed for tHey using enzyme immuno-assay; Total Cholesterol (TC) and triglycerides using enzymatic colorimetric method; High Density Lipoprotein Cholesterol (HDL-C) with phosphotungstate magnesium precipitation; and Apolipoprotein-A1 (Apo-Al) by turbidimetric method. Serum folate, pyridoxine (B₆) and cyanocobalamin (B₁₂) were determined using high performance liquid chromatography and Serum Creatinine (SC) with fixed-time Jaffe method. Low Density Lipoprotein Cholesterol (LDL-C) was estimated by means of Friedewald formula. Data were analysed using descriptive statistics. Student's t'test and Mann-Whitney U test at p=0.05. The mean age for NS and control were 103.5 ± 32.7 and 100.9± 29.4 months respectively. The mean BMI of NS (17.3 ± 1.6 kg/m² ) was significantly higher than that of control (15.9± 1.2 kg/m²). At baseline, NS had significantly higher value than control with respect to tHcy (11.3 ± 2.6 umol/L versus 5.5 ± 2.3 umol/L), TC (238.8±93.9 mg/dL versus 155.0 ±70.6 mg/dL), triglycerides (161.5 ± 114.4 mg/dL versus 108.4 ± 52.6 mg/dL), LDL-C (191.9 ± 91.2 mg/dL, versus 122.5 ± 70.2 mg/dL) and Apo-AI (173.8 ± 43.4 mg/dL, versus 136.7± 56.9 mg/dL) but no significant difference in HDL-C. In addition, NS had significantly lower values than control for folate (9.1 ± 3.9 ng/mL versus 11.2± 3.1 mg/mL) and cyanocobalamin (268.5 ± 95.7 pg/mL versus 316 ±117.2 pg/mL). The concentrations of pyridoxine (NS: 72.4 ±13.1 nmol/L; control: 75.8 ± 15.2 nmol/L) and creatinine (NS: 0.7 ± 0.4 mg/dL; control: 0.5 ± 0.2 mg/dL) were not significantly different. Vitamin supplementation significantly different. Vitamin supplementation significantly lowered tHcy by 52.6%, TC by 21.1%, triglycerides by 26.1%, LDL-C by 21.2%, Apo-AI by 12.5%, creatinine by 28.6%; but increased folate by 26.4%, cyanocobalamin by 15.4% and pyridoxine by 15.3% when compared with the respective baseline values. Elevated plasma homoocysteine and atherogenic lipids were associated with low serum folate and cyanocobalamin in children with nephrotic syndrome. These abnormalities were improved by supplementation with oral vitamins.