Caregiver Burden with Duchenne and Becker Muscular Dystrophy in Japan: A Clinical Observation Study

Objective Skeletal muscle weakness and cardiomyopathy can be seen in carriers of dystrophinopathy. Therefore, the health management of caregivers of Duchenne/Becker muscular dystrophy (DMD/BMD) patients who are themselves carriers is an important issue. However, few studies have focused on caregivers who have dystrophin mutations. Methods In this cross-sectional study conducted at five hospitals, the daily living, situation medical treatment status, genetic testing, physical assessment, care burden, and quality of life of caregivers of DMD/BMD patients were surveyed. Results The subjects were 36 main caregivers (mean age 55.7 +/- 8.4 years old), of whom 52.8% were diagnosed as carriers, 8.3% were noncarriers, and 38.9% were not confirmed. In addition, half of the caregivers were not examined regularly at medical institutions. Of all caregivers, 54.3% had muscle or cardiac symptoms, and 75% had elevated serum creatine kinase levels. The mean Zarit Caregiver Burden Interview (ZBI) total score of current caregivers was 20.9 +/- 13.1. The frequency of a ZBI total score >= 25 was significantly higher in caregivers diagnosed as carriers than in caregivers unexamined as carriers (p=0.04). The healthrelated quality of life score (Short Form 36; SF-36) in caregivers was slightly lower than the Japanese standard scores in the sections of physical functioning, role limitations-physical, bodily pain, and social functioning. Conclusion Some caregivers of DMD/BMD patients can themselves have muscular or cardiac symptoms and a heavy care burden. It is therefore necessary for carrier caregivers, especially women, to undergo regular health checkups and receive appropriate health management.