Phenylketonuria (PKU), a rare metabolic disorder, causes cognitive impairment unless treated with a strict, protein-restricted diet, but few studies have examined the relationship between treatment compliance and parental wellbeing. In the present study, 46 primary caregivers of children with PKU completed measures of psychological distress, parenting stress (related to caring for a child with an illness), resilience, perceived social support and child dependency. Treatment adherence was assessed using the proportion of blood phenylalanine concentrations within target range in the preceding year. Results indicated that 59% of caregivers showed clinical levels of psychological distress, which was predicted by their parenting stress and resilience. Whilst the proportion of blood phenylalanine concentrations in range was not associated with parental distress, it was predicted by child age and caregiver's perceived support from family. Despite experiencing high levels of distress, the results indicated that caregivers' ability to adhere to treatment was not affected. Interventions to reduce parenting stress and boost caregiver resilience may have a positive effect on parental wellbeing. Additionally, interventions to promote treatment adherence benefit parents of older children, with a focus on promoting support from family members. Further research with larger sample sizes and longitudinal designs is needed to further establish causal mechanisms.
Keywords: Adherence; Children; Distress; Parent; Phenylketonuria; Wellbeing.