New Evidence for the Phosphorus-Lowering Effects of Niacin

Article Outline

• Acknowledgements
• References
• Copyright

To the Editor:

The April issue of the American Journal of Kidney Diseases included 2 editorials on niacin: my contention that niacin's omission from the recent KDIGO (Kidney Disease: Improving Global Outcomes) bone guideline was unjustified,¹ and a rejoinder from Moorthi et al² arguing that the evidence for its inclusion was inadequate. I have 2 brief comments regarding the points raised by Moorthi et al. First, niacin compounds—niacin (short or long acting), niceritrol, and niacinamide—are not “phosphate binders.” Indeed, their elegant phosphorus-lowering mechanism does not require multiple dosing, high pill burden regimens timed requisitely to meal ingestion, precisely because niacin compounds do not simply trap food-bound phosphorus liberated in the gut. Rather, as I described,² niacin compounds reduce active transport–mediated phosphorus absorption by their direct inhibitory action on the intestinal cotransporter (NaPi-2b; also known as Npt2b and encoded by the SLC34A2 gene).

Second, since my editorial went to press, our unique placebo-controlled data from a 6-month study of 1,547 patients were published,³ irrefragably demonstrating that extended-release niacin causes a sustained reduction in serum phosphorus concentrations across a spectrum of kidney function corresponding to estimated glomerular filtration rates of 30-90 mL/min/1.73 m² (0.50-1.50 mL/s/1.73 m²) and greater. Moreover, this clear phosphorus-lowering effect of extended-release niacin was apparent among the 215 patients with estimated glomerular filtration rates of 30-59 mL/min/1.73 m² (0.50-0.98 mL/s/1.73 m²), stage 3a and 3b chronic kidney disease, specifically. I anticipate eagerly seeing these data added to the next available KDIGO update.

Back to Article Outline

Acknowledgements 

Financial Disclosure: The author declares that he has no relevant financial interests.

Back to Article Outline

References 

1. Bostom A. Binder blinders: niacin of omission?. Am J Kid Dis. 2010;55(4):628–630
   • View In Article
2. Moorthi RN, Moe SM, Drueke T, Uhlig K. All research does not a guideline make!. Am J Kid Dis. 2010;55(4):631–634
   • View In Article
3. Maccubbin D, Tipping D, Kuznetsova O, Hanlon WA, Bostom AG. Hypophosphatemic effect of niacin in patients without renal failure: a randomized trial. Clin J Am Soc Nephrol. 2010;5(4):582–589
   • View In Article
   • CrossRef