Predictors of Health-Related Quality of Life in boys with Duchenne muscular dystrophy from six European countries.

Duchenne muscular dystrophy (DMD) is a progressive, genetically determined neuromuscular disease that affects males and leads to severe physical disability in early teenage years. Over the last decades, patient-reported outcomes such as Health-Related Quality of Life (HRQoL) gained great interest in clinical research. However, little is known about factors affecting HRQoL in boys with DMD. Data from the multi-center CARE-NMD project of boys with DMD from six European countries collected between 2011 and 2012 were analyzed (8-17 years old; n = 321). HRQoL was measured using the KIDSCREEN-10 index, the Pediatric Quality of Life Inventory (PedsQL) and the Neuromuscular Module of the PedsQL (NMM). Linear regression models served to examine influences of socio-demographic, disease- and treatment-specific as well as participation- and environment-related factors on overall and disease-specific HRQoL. Proportions of explained variance varied across models using different outcomes (18-34%). Overall HRQoL according to the KIDSCREEN-10 index was associated with household income, the frequency of attending a clinic with specialized staff, the number of days spent outside home, and the attitude of the local community, but no significant association with age occurred. Overall HRQoL according to the generic PedsQL and disease-specific HRQoL were both positively associated with age and influenced by the country of residence, the disease stage, number of days spent outside home, and the attitude of the local community. Our results may be relevant for clinical practice and planning interventions for this population, but should be confirmed by future research. Further questions for future studies on boys with DMD are proposed.