Determinants of Quality of Life in Children with Inborn Errors of Metabolism Receiving a Restricted Diet

Objective To investigate the determinants of quality of life (QoL) in children with inborn errors of metabolism with restricted diet (IEMRDs) using a single theory-based multidimensional model. Study design In this multicenter cross-sectional study, data from children with IEMRDs (except phenylketonuria) aged 8 to 17 years and their parents were collected from January 2015 to December 2017. Measurements included a child’s self-reported QoL, self-rated behavioral problems and anxiety, and parental anxiety. Based on hypotheses from a literature-built theoretical model linking demographic, clinical, family environment and psychosocial characteristics to QoL either directly or indirectly, associations of these factors with a child's self-rated QoL were examined using a structural equation modeling (SEM) approach. Results A total of 312 children (mean [SD] age, 12.2 [2.6] years; 160 [51%] boys) were included. Higher trait anxiety and behavioral problems in children were the most important factors associated with poorer QoL (standardized path coefficients = −0.71 and −0.23, respectively). Additionally, higher parent trait anxiety, younger age at diagnosis, and having a disease requiring an emergency diet were associated with poorer QoL in these children. The final model fit the data closely according to conventional goodness-of-fit statistics and explained 86% of QoL variance. Conclusions Psychosocial factors appear to be major determinants of QoL impairment in children with IEMRDs. These factors should be particularly addressed in clinical practice as part of the global treatment plan for a child with IEMRD. Future studies based on longitudinal design should consider coping strategies when exploring potential predictive factors of QoL.