The prevalence and severity of disease-related disabilities and their impact on quality of life in neuromuscular diseases

Purpose: People with neuromuscular disease experience lower quality of life levels than people from the general population. We examined the prevalence and severity of a broad range of neuromuscular disease-related disabilities and their impact on health-related quality of life. Materials and methods: A cross-sectional postal survey study was conducted among patients diagnosed with neuromuscular disease. Patients completed the Neuromuscular Disease Impact Profile, a disease-related disability impact questionnaire, and two generic health-related quality of life questionnaires: the medical outcome study Short Form Questionnaire and the World Health Organization Quality of Life-bref. The impact of disabilities on quality of life was estimated using multiple regression analyses. Results: Six hundred sixty two patients (68% response rate) completed the questionnaires. There were no differences in quality of life between diagnosis-based subgroups. 'Impairments in muscle functions' had the highest prevalence and severity scores in the total sample and diagnosis-based subgroups. Neuromuscular disease-related disabilities showed strong and independent associations with all aspects of health-related quality of life. 'Impairments in mental functions and pain' was the most important predictor of health-related quality of life followed by 'restrictions in participation in life situations'. Conclusions: Although 'impairment in muscle functions' is the most prevalent and severe disability, the 'impairments in mental functions and pain' have a strong association with health-related quality of life in patients with a neuromuscular disease.