Objective: Non-calcium containing phosphate binders (non-CPBs) are useful for the treatment of hyperphosphatemia without a concern of hypercalcemia in patients undergoing dialysis. However, due to their relatively high cost, prescribing non-CPBs is restricted in South Korea. This study was conducted to investigate prescribing patterns, especially switching between CPBs and non-CPBs, in dialysis patients in a real-world setting.
Materials and methods: This is an observational study using the National Health Insurance Service claim data. The study population included patients who initiated dialysis between July 2012 and June 2013 and were prescribed phosphate binders at least once during the observation period (2012 - 2016) (n = 10,073). Medication costs and prescribing patterns including switching of phosphate binders were investigated.
Results: Compared with the first year of dialysis, the costs of phosphate binders more than doubled during the 4th year of dialysis (from US$ 28.4 to US$ 60.1), largely due to an increase in the cost of non-CPBs (from US$ 117.5 to US$ 237.8). Many patients continued to change drugs between CPBs and non-CPBs. The continuous prescription period of CPBs was shortened each time a drug was changed. A total of 551 patients (13.4%) changed their medication three times between CPBs and non-CPBs.
Conclusion: Over time on dialysis, use of non-CPB increased and medication costs increased accordingly. Many patients continued to change drugs between CPBs and non-CPBs due to the restricted criteria of the health insurance. Further outcome research is necessary to evaluate the appropriateness of the clinical practice in which CPBs and non-CPBs are alternately used.