Caregiver Burden and Related Factors Among Caregivers of Patients with Myotonic Dystrophy Type 1

Background: Multi-systemic symptoms of varying severity in myotonic dystrophy type 1 (DM1) may pose difficulties in caregiving. However, the factors which affect their care burden are yet to be sufficiently understood. Objective: We investigated care burden and its correlates among caregivers of patients with DM1. Methods: General demographic information was obtained from patients with DM1, as well as Barthel index (ADL), body mass index, and genetic information. Patients completed SF-36v2 (health-related quality of life), CES-D (depressive symptoms), and ESS (daytime sleepiness) questionnaires. Caregivers reported their perception of patient's status through these questionnaires, and completed Zarit Caregiver Burden Interview (ZBI). Correlation analysis of these variables were performed, and regression analysis was utilized to assess the relationship between caregiver burden and other variables. Results: Forty-three patient-caregiver dyads participated. Mean ZBI score was 20.7 +/- 17.4, and 32.6% reported a significant care burden. ZBI correlated with caregiver-reported CES-D, but not with patient-reported CES-D. Both patient-reported and caregiver-reported physical QoL of patients correlated with patient ADL. Multiple regression analysis revealed that the combination of caregiver-reported CES-D, caregiver-reported mental QoL, and genetic characteristics predicted caregiver burden. Conclusions: Caregiver burden was felt although patients were relatively well-functioning. Patients' and caregivers' assessment of patients' physical condition were similar. However, they did not agree on the evaluation of the patients' psychological state. Cognitive characteristic of the patients and the caregivers' perception of the patients' state may have affected the results. Future DM1 care strategies need to work on improvement of patient-caregiver communication and provide support for the caregiver's psychological health.