A COMBINED, TAILORED PHARMACIST INTERVENTION WITH DOSE OPTIMIZATION OF PHOSPHATE BINDING DRUGS TO IMPROVE PHOSPHATE CONTROL IN PATIENTS ON DIALYSIS

Abstract

Background: Hyperphosphatemia is a common complication in end-stage renal disease (ESRD) patients despite phosphate binder treatment. Low adherence to phosphate binders due to a high pill burden is an important factor. A combined, tailored pharmacist intervention with dose optimization was implemented focusing on therapeutic-related factors and patient-related factors to obtain phosphate control in hemodialysis (HD) patients. Methods: This study was conducted at a hospital in The Netherlands as a single-centre, intervention study with a within patient pre-post design. In order to identify potential patient adherence barriers, we implemented an individualized intervention. Firstly, multiple pharmacist counselling sessions were performed to identify potential patient adherence barriers with Quick Barrier Scan (QBS), the medication adherence was investigated with the Medication Adherence Report Scale (MARS-5) and the Recognizing and Addressing Limited Pharmaceutical Literacy (RALPH) interview guide was used to explore the patients’ health literacy. Secondly, the pharmacist implemented tailored intervention with dose optimization. Finally, the serum phosphate control was evaluated after the intervention. Results: A total of 28 patients were enrolled in the study for the analysis of serum phosphate level and MARS-5. Mean baseline serum phosphate level was 2.02 mmol/L (SD = 0.45). Serum phosphate level at month 1 decreased to 1.86 mmol/L (SD=0.43). A similar result was found for month 2 and 3 (1.98 mmol/L). However, the paired T-test showed no significant effect in changes in serum phosphate level between pre-intervention and 1,2 and 3 months after intervention (p = 0.125, p = 0.630 and p = 0.690). In addition, the percentage of patients with phosphate regulation (≤ 1.50 mmol/L) increased from 0% (n=28) at baseline, to 21.4%% (n=28) and 17.9% (n=27) and 14.3% (n=28) for 1,2 and 3 months after the intervention respectively. Total MARS-5 scores at pre-intervention resulted in a median (IQR) score of 0.3 (0.0-0.6) and a median (IQR) score of 4.8 (0.4 – 5.0) 3 months after the intervention. Conclusion: This study highlights the importance of personalized patient counselling sessions in combination with lowering phosphate binder pill burden to positive effects on the serum phosphate levels and phosphate binder adherence. However, the change in serum phosphate level was no significant. Notwithstanding the relatively limited sample size, this study offers valuable insights into personalized intervention with dose optimization to improve phosphate control. Therefore, this study lays the groundwork for future research into personalized intervention strategies.