Differences in respiratory function, depressive symptoms and quality of life between patients with hereditary motor and sensory neuropathy and myotonic dystrophy undergoing maintenance rehabilitation.

Hereditary motor and sensory neuropathy (HMSN) and myotonic dystrophy (MD) are chronic neuromuscular diseases that cause progressive muscular impairment and impact patient's quality of life. Conflicting findings in existing literature underscore the need for focussed research on specific health aspects in these patients. The aim of the study was to explore the differences in respiratory function, depressive symptoms and quality of life between patients with HMSN and MD undergoing maintenance rehabilitation. Our prospective observational study included 62 HMSN patients (median age 53.5, range 19-79 years; 38 women) and 50 MD patients (median age 54.0, range 18-77 years; 34 women) undergoing maintenance rehabilitation. They performed respiratory function tests (vital capacity, forced vital capacity, forced expiratory volume and peak expiratory flow) and respiratory muscle strength tests (maximum inspiratory pressure, maximum expiratory pressure and sniff nasal inspiratory force). The Center for Epidemiological Studies-Depression Scale was used to evaluate depression, and their health-related quality of life was assessed using the Quality of Life in Genetic Neuromuscular Disease Questionnaire. Using logistic regression, we examined group-difference in presence of depressive symptoms while accounting for age, symptoms duration, and marital status. Multiple linear regression was used to assess the difference in quality-of-life scores, adjusting for age, gender, and symptoms' duration. The HMSN group achieved statistically significantly better results than the MD group on all respiratory measures (about 17% absolute difference in the respiratory function measures and 30% relative difference in the respiratory muscle strength measures on average). Both groups exhibited a high level of depression symptoms (HMSN 24%, MD 44%; estimated adjusted odds-ratio MD vs. HMSN 1.9, 95% CI 0.8-4.5, P  = 0.127). We did not find a statistically significant difference between the groups regarding quality-of-life domains, though a trend towards better quality-of-life among the HMSN patients could be observed. The implication for future practice is that the MD patients would potentially benefit the most from targeted respiratory-rehabilitation interventions, and both groups could benefit from focussed mental-health interventions.