Variability in Cinacalcet Prescription across US Hemodialysis Facilities.

BACKGROUND AND OBJECTIVES: Calcimimetic drugs used to treat secondary hyperparathyroidism are being considered for inclusion in the Medicare ESRD Prospective Payment System bundle after an evaluation period. Understanding of utilization patterns of calcimimetics across dialysis facilities may help align financial incentives with clinical objectives. Our study's purpose was to describe the distribution of cinacalcet prescription across United States hemodialysis facilities and to explore factors that may influence cinacalcet utilization. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We used monthly cross-sectional data from the Dialysis Outcomes and Practice Patterns Study in 2014 to characterize the distribution of cinacalcet prescription across 203 United States hemodialysis facilities (10,521 patients). On the basis of associations with parathyroid hormone levels from patient-level analyses, we used linear mixed-effects regressions to estimate the associations between three facility-level exposures (black race, <65 years old, and having ≥3 years on dialysis [vintage]) and the prevalence of cinacalcet prescription, adjusting for facility- and patient-level potential confounders.
RESULTS: The mean percentage of patients in each facility with cinacalcet prescription was 23% in June 2014 (median, 22%; interquartile range, 13%-30%). Adjusted for facility-level and nonexposure patient-level variables, the difference in prevalence of cinacalcet prescription between facilities with the highest and lowest quartiles of percentage of black patients was 7.8% (95% confidence interval [95% CI], 0.8% to 14.8%; P for trend =0.03). The adjusted prevalence difference was 7.3% for the percentage of patients aged <65 years (95% CI, -0.1% to 14.7%; P for trend =0.06) and 11.9% for the percentage of patients with ≥3 years of dialysis (95% CI, 2.4% to 21.4%; P for trend =0.02). These associations changed appreciably, becoming much weaker or even reversing, after further adjusting for the patient-level exposure variables.
CONCLUSIONS: Facilities treating more patients who are black, under age 65 years, and having dialysis vintage ≥3 years have higher average levels of cinacalcet prescription. However, these differences were strongly attenuated after accounting for the unbalanced distributions of these patient case-mix variables.