Trends in mineral metabolism treatment strategies in patients receiving hemodialysis in the United States

Background and objectives With multiple medications indicated for mineral metabolism, dialysis providers can apply various strategies to achieve target phosphate and parathyroid hormone (PTH) levels. We describe common prescribing patterns and practice variation in mineral metabolism treatment strategies over the last decade. Design, setting, participants, & measurements In a cohort of adults initiating hemodialysis at Dialysis Clinic, Inc. facilities, we assessed prescriptions of vitamin D sterols, phosphate binders, and cinacalcet longitudinally. To identify the influence of secular trends in clinical practice, we stratified the cohort by dialysis initiation year (2006–2008, 2009–2011, and 2012–2015). To measure practice variation, we estimated the median odds ratio for prescribing different mineral metabolism treatment strategies at 12 months post–dialysis initiation across facilities using mixed effects multinomial logistic regression. Sensitivity analyses evaluated strategies used after detection of first elevated PTH. Results Among 23,549 incident patients on hemodialysis, there was a decline in vitamin D sterol–based strategies and a corresponding increase in strategies without PTH-modifying agents (i.e., phosphate binders alone or no mineral metabolism medications) and cinacalcet-containing treatment strategies between 2006 and 2015. The proportion with active vitamin D sterol–based strategies at dialysis initiation decreased across cohorts: 15% (2006–2008) to 5% (2012–2015). The proportion with active vitamin D sterol–based strategies after 18 months of dialysis decreased across cohorts: 52% (2006–2008) to 34% (2012–2015). The odds of using individual strategies compared with reference (active vitamin D sterol with phosphate binder) varied from 1.5-to two-fold across facilities in 2006–2008 and 2009–2011 cohorts, and increased to two-to three-fold in the 2012–2015 cohort. Findings were similar in sensitivity analyses starting from first elevated PTH measurement. Conclusions Over time, mineral metabolism management involved less use of vitamin D sterol–based strategies, greater use of both more conservative and cinacalcet-containing strategies, and increased practice variation, suggesting growing equipoise.