Barriers to and Facilitators of Phosphate Control in Children With CKD

Managing mineral and bone disorder in children with chronic kidney disease (CKD) requires control of serum phosphate levels. However, hyperphosphatemia is common, particularly in adolescents, reflecting suboptimal adherence to phosphate-binder medications and a reduced phosphate diet. We explored phosphate-related knowledge and adherence barriers in children, and their caregivers, using a sequential explanatory mixed-methods study design.

Children aged 8 to 18 years with CKD stages 4 and 5, on dialysis or post-transplantation, and caregivers, were recruited from 3 UK pediatric kidney centers. The Phosphate Understanding and Knowledge Assessment questionnaire was used to assess knowledge. Online focus groups explored real-world challenges to phosphate control.

Forty-eight children and 43 caregivers were recruited; 44 (92%) children and 33 (75%) caregivers completed the questionnaire. Median knowledge scores were 64.3% (interquartile range, 55.3-78.6) for children and 72.7% (interquartile range, 64.3-85.7) for caregivers (P = 0.04). Older children scored higher (P = 0.01, R ² = 0.13), but knowledge did not correlate with serum phosphate. Dietary restriction was perceived as more challenging than using phosphate-binders (59% children; 71% caregivers). Forty-six participants, including 30 child-caregiver dyads, joined focus groups. The following 5 themes were identified encapsulating the experiences of families: practical advice and support are valued; personalized strategies are preferred to facilitate sense-making; the social environment of the child and family is disrupted; education and self-management skills can influence success; and the journey requires acceptance, adaptation, and perseverance.

In pediatric CKD, poor adherence to phosphate advice originates more from social and practical barriers than knowledge deficits. Our findings can inform personalized strategies to improve adherence in real-world settings.