Barriers to medication adherence and its relationship with outcomes in pediatric dialysis patients

Medication adherence is a major factor determining outcome in children with chronic disease. Children with end-stage renal disease are challenged with requirements for renal replacement therapy in addition to complicated medication regimens. We assessed barriers to medication adherence in 22 pediatric patients receiving chronic dialysis [63.6 % hemodialysis (HD), 36.4 % peritoneal dialysis (PD); age 15.9 +/- 0.7 years, dialysis vintage 31.6 +/- 6.5 months]. Adherence was assessed by a 16-question survey with a maximum score (difficulty) of 64. The overall mean adherence score was 30.9 +/- 2.4 (range 16-49; median 27.5). There was a trend for lower adherence scores in patients on HD (27.5 +/- 2.9) compared to those on PD (36.8 +/- 3.7) (p = 0.06). Compared to HD patients, the mean score/question was significantly higher in PD patients (1.7 +/- 0.2 vs. 2.4 +/- 0.2, respectively; p = 0.006). Of the 16 questions, HD and PD patients gave a mean response of a parts per thousand currency sign1.2 for five and zero questions, respectively. Neither gender, age nor dialysis vintage was related to adherence scores. There was also a trend for adherence scores to be higher in females (35.6 +/- 3.7) than in males (27.5 +/- 2.9) (p = 0.1), but this difference did not reach statistical significance. Markers of mineral bone disease were similar in HD and PD patients. Among all targets in HD and PD patients combined, there was no relationship between adherence scores and number of targets reached (r = -0.09, p = 0.7). There are many barriers to medication adherence in pediatric patients receiving dialysis. In our patient group the difficulties were more evident in patients receiving PD than in those receiving HD.