Effect of low dose nicotinic acid on hyperphosphatemia in patients with end stage renal disease.

Hyperphosphatemia is a risk factor for ectopic calcification and coronary artery diseases in end stage renal diseases (ESRD). The aim of this study was to assess the effect of low-dose nicotinic acid on hyperphosphatemia in patients with ESRD. This randomized, double-blind clinical trial was done on 70 ESRD patients with serum phosphoure ≥5.5 mg/dl. Patients were randomly divided into two equal groups (n = 35) and the intervention group received niacin 25 mg/day as the initial dose. After 4 weeks, in patients who did not respond to treatment, niacin dose was increased up to 50 mg/dl. At the end of week 8, in case there was no treatment effect, the dose was raised to 100 mg/day. The appropriate response to treatment was defined as serum phosphorous level reductions <5.5 mg/dl. The age was 50.5 ± 14.3 years and duration of dialysis 5.1 ± 5.3 months. In the niacin group, mean phosphorus level decreased from 6.7 ± 0.84 mg/dl at the end of the 1(st) month to 5.8 ± 1.0 mg/dl at the end of the 2(nd) month and to 4.4 ± 1.4 mg/dl at the end of the 3(rd) month (P = 0.004). In the placebo group, mean phosphorus level increased from 6.5 ± 1.2 mg/dl to 7.2 ± 0.91 mg/dl at the end of the 3(rd) month (P = 0.006). In the niacin group, high density lipoprotein (HDL) increased significantly from 45.00 ± 14.9 to 47.2 ± 11.6 (P = 0.009). We conclude that niacin (100 mg/day) decreased phosphorus serum level and increased HDL serum level in patients on dialysis.