Prevalence and Correction of 25(OH) Vitamin D Deficiency in Peritoneal Dialysis Patients

Abstract

Background Peritoneal dialysis (PD) patients are at risk for 25(OH) vitamin D deficiency due to effluent loss in addition to traditional risk factors. Objectives To measure 25(OH) vitamin D deficiency in prevalent PD patients, to evaluate a replacement dose, and to determine the effects of correction. Methods 25(OH) vitamin D levels were drawn on prevalent PD patients. Patients deficient in 25(OH) vitamin D were given ergocalciferol, 50 000 IU orally once per week for 4 weeks. Patients scored muscle weakness, bone pain, and fatigue on a scale of 0 (none) to 5 (severe). Serum calcium, phosphate, parathyroid hormone (PTH), and 25(OH) vitamin D, and 1,25(OH)2 vitamin D levels were obtained before and after treatment. Results 25(OH) vitamin D levels were measured in 29 PD patients. Deficiency (<15 ng/mL) was found in 28/29 (97%); 25/29 (86%) had undetectable levels (<7 ng/mL). One course of ergocalciferol corrected the deficiency in all but 1 patient, who required a second course. Scores for muscle weakness and bone pain fell from pre- to posttreatment ( p < 0.001). 1,25(OH)2 vitamin D levels rose post ergocalciferol (from 20 to 26 pg/mL, n = 20, p = 0.09). Serum calcium, phosphate, and PTH levels did not change with ergocalciferol. Conclusions Most PD patients had marked 25(OH) vitamin D deficiency, which was readily and safely corrected with one course of 50000 IU ergocalciferol, having no effect on serum calcium, phosphorus, or PTH, but complaints of muscle weakness and bone pain decreased. A prospective, placebo-controlled double-blinded study is needed to determine whether replacement of 25(OH) vitamin D is beneficial in PD patients.