Utilization and costs of medications associated with CKD mineral and bone disorder in dialysis patients enrolled in Medicare Part D

Am J Kidney Dis. 2014 Nov;64(5):770-80. doi: 10.1053/j.ajkd.2014.04.014. Epub 2014 May 13.


Background: Information is limited regarding utilization patterns and costs for chronic kidney disease-mineral and bone disorder (CKD-MBD) medications in Medicare Part D-enrolled dialysis patients.

Study design: Retrospective cohort study.

Setting & participants: Annual cohorts of dialysis patients, 2007-2010.

Predictors: Cohort year, low-income subsidy status, and dialysis provider.

Outcomes: Utilization and costs of prescription phosphate binders, oral and intravenous vitamin D analogues, and cinacalcet.

Measurements: Using logistic regression, we calculated adjusted odds of medication use for low-income subsidy versus non-low-income subsidy patients and for patients from various dialysis organizations, and we report per-member-per-month and average out-of-pocket costs.

Results: Phosphate binders (∼83%) and intravenous vitamin D (77.5%-79.3%) were the most commonly used CKD-MBD medications in 2007 through 2010. The adjusted odds of prescription phosphate-binder, intravenous vitamin D, and cinacalcet use were significantly higher for low-income subsidy than for non-low-income subsidy patients. Total Part D versus CKD-MBD Part D medication costs increased 22% versus 36% from 2007 to 2010. For Part D-enrolled dialysis patients, CKD-MBD medications represented ∼50% of overall net Part D costs in 2010.

Limitations: Inability to describe utilization and costs of calcium carbonate, an over-the-counter agent not covered under Medicare Part D; inability to reliably identify prescriptions filled through a non-Part D reimbursement or payment mechanism; findings may not apply to dialysis patients without Medicare Part D benefits or with Medicare Advantage plans, or to pediatric dialysis patients; could identify only prescription drugs dispensed in the outpatient setting; inability to adjust for MBD laboratory values.

Conclusions: Part D net costs for CKD-MBD medications increased at a faster rate than costs for all Part D medications in dialysis patients despite relatively stable use within medication classes. In a bundled environment, there may be incentives to shift to generic phosphate binders and reduce cinacalcet use.

Keywords: Chronic kidney disease (CKD); Medicare Part D; calcimimetics; dialysis; medication costs; mineral and bone disorder; phosphate binders; vitamin D analogues.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Bone Diseases / economics*
  • Bone Diseases / epidemiology
  • Bone Diseases / therapy*
  • Cinacalcet
  • Drug Utilization / economics*
  • Female
  • Health Expenditures
  • Humans
  • Male
  • Medicare Part D / economics*
  • Middle Aged
  • Naphthalenes / economics
  • Naphthalenes / therapeutic use
  • Phosphate-Binding Proteins / economics
  • Phosphate-Binding Proteins / therapeutic use
  • Poverty / economics
  • Renal Dialysis / economics*
  • Renal Insufficiency, Chronic / economics*
  • Renal Insufficiency, Chronic / epidemiology
  • Renal Insufficiency, Chronic / therapy*
  • United States / epidemiology
  • Vitamin D / economics
  • Vitamin D / therapeutic use
  • Young Adult


  • Naphthalenes
  • Phosphate-Binding Proteins
  • Vitamin D
  • Cinacalcet