The Relation between Vitamin D Status and Anemia in Patients with End Stage Renal Disease on Regular Hemodialysis

Abstract

Abstract Background Anemia is a common complication in end stage renal disease patients on regular hemodialysis (HD). several factors are linked to the pathogenesis of anemia in this population. There has been a lot of interest in the non-classical effects of vitamin D, including its association with erythropoiesis and anemia pathogenesis. Objectives To establish whether there is an association between anemia and the status of 25 OH (Hydroxy) vitamin D level in dialysis patients Methods This study is a cross sectional study that enrolled 90 patients on regular hemodialysis. Laboratory tests included Serum calcium, phosphorus, 25(OH) vitamin D and intact parathyroid hormone (iPTH) levels, Hemoglobin level, ferritin level, serum iron, total iron binding capacity and calculation of transferrin saturation. 25(OH) vitamin D level was measured by ELISA (Calbiotech. USA, REF: VD2208. Vitamin D status was classified into deficient (< 20 ng/ml), insufficient (20-30 ng/ml) and sufficient (>30 ng/ml). Results The level of Vitamin D measured in the patients ranged between 3.5 to 66 ng/ml with median 16.35 (8 – 34). 24 patients had vitamin D deficiency (vitamin D levels < 20 ng/dl), Patients with insufficient levels (vitamin D levels 20-30 ng/dl) were 32 patients, while patients with sufficient (> 30 ng/dl) levels were 34 patients. there were no statistically significant relations between vitamin D levels and the gender of the patients (p = 0.536), their age (p = 0.973), duration of HD (p = 0.600), Diabetes mellitus (p = 0.064) and hypertension (p = 0.249). There were statistically significant positive correlations between Vitamin D levels and the level of hemoglobin of the patients (P = 0.000), serum calcium levels (P = 0.000) and serum PO4 levels (P = 0.023). However, significant negative correlation between Vitamin D levels and serum iPTH levels (p = 0.000), serum iron (p = 0.019) and Transferrin saturation (%) (p = 0.012). Using Spearman correlation coefficient, there were highly significant positive correlations between vitamin D3 levels in all patients and both hemoglobin levels (p = 0.000) and serum calcium levels (p = 0.000). Meanwhile, there were highly significant negative correlations between vitamin D3 levels in all patients and serum iPTH levels (p = 0.000) and T.SAT of the patients (p = 0.003). Conclusion There was a significant association between the status of vitamin D and the level of hemoglobin in dialysis population who were studied, other associations with hemoglobin levels included PTH level and calcium.