Burden of caregivers of patients with neuronopathic and non-neuronopathic Gaucher disease in Japan: A survey-based study

Background: Gaucher disease (GD), a rare lysosomal storage disorder, is associated with considerable patient and caregiver burden. We examined the applicability of existing caregiver questionnaires and assessed the level of burden in caregivers of patients with GD.Methods: This cross-sectional, non-interventional study was conducted in Japan. Caregivers of patients with confirmed GD (any type) were recruited (patient association group and referral) for pre-testing (May 2021) or the main survey (October-December 2021). Caregivers completed the Caregiver Impact Questionnaire (CIQ; 30 items) and Zarit Caregiver Burden Interview (ZBI; 22 items) on paper. Total CIQ and ZBI scores and subscores were determined overall and by GD type. Inter-item correlations and test-retest reliability (2 rounds, 2 weeks apart) were calculated. The relationship between caregiving duration and caregiver burden was also analyzed.Results: Nine caregivers (type 2 [GD2]: n = 6; type 3 [GD3]: n = 3) and 25 caregivers (type 1 [GD1]: n = 2; GD2: n = 17; GD3: n = 6) completed the pre-test and main survey, respectively. In the main survey, mean total CIQ score, all CIQ subscores (except emotional function), and total ZBI score were highest in caregivers of patients with GD2 compared with caregivers of patients with GD1/GD3. High test-retest reliability (Kappa >0.6) was observed for 15 CIQ items and 16 ZBI items. CIQ and ZBI scores appeared to be positively correlated with each other and negatively correlated with caregiving duration. Conclusions: The CIQ and ZBI are applicable, reliable measures to assess burden in caregivers of patients with GD in Japan. Caregiver burden was highest in caregivers of patients with GD2 and decreased with caregiving duration.