Vitamin D Level in Predialysis Chronic Kidney Disease Patients Stage 3 to 5 and Predictors of its Deficiency

Abstract

Background: Vitamin D deficiency is commonly encountered in patients with chronic kidney disease (CKD) with or without undergoing dialysis. This study was conducted to assess vitamin D level in patients diagnosed with predialysis CKD stage 3 – 5, and to determine the predictors of its deficiency in such patients. Materials and Methods: This cross-sectional study included 75 patients who were divided into three equal groups of CKD-3, CKD-4 and CKD-5. All cases were subjected to detailed history taking, physical examination and measurement of estimated glomerular filtration rate (eGFR) according to Cockcroft-Gault formula. In addition, laboratory investigations included CBC, renal function tests, serum ferritin, intact parathyroid hormone (iPTH) and vitamin D level. Results: Patient demographics and other co-morbidities were comparable among the three groups. Serum vitamin D had mean values of 24.84, 20.52 and 11.24 ng/ml in patients with stages III, IV and V respectively, with significant difference between the three groups. Vitamin D deficiency was more common in CKD-5 cases. On the contrary, serum parathyroid hormone and ferritin were significantly higher levels, in patients with higher stages. There was statistically significant positive correlation of serumvitamin D with eGFR, Hb, calcium and albumin. On the other hand, serum vitamin D was negatively correlated with phosphate, PTH, urea andcreatinine. Conclusion: It is evident that higher stages of CKD are associated with more vitamin D deficiency.