The Caregiver Burden Inventory in evaluating the burden of caregivers of elderly demented patients: results from a multicenter study

Background and aims: The burden perceived by caregivers of patients with dementia is a fundamental prognostic aspect in the history of the disease. The aim of this study was to demonstrate the internal consistency of the Caregiver Burden Inventory (CBI), a scale used to quantify burdens in different aspects of a caregiver's life, and the influence of patients' and caregivers' characteristics on its different dimensions. Methods: In this cross-sectional study, 419 demented patients and their caregivers were evaluated in 16 geriatric centers in Italy. Cognitive status and behavioral disturbances were assessed by the Mini Mental State Examination (MMSE) and Neuropsychiatric Inventory (NPI), respectively. Activities of Daily Living (ADL) and Instrumental Activities of Daily Living (IADL) were also evaluated. Comorbidity was assessed by the Cumulative Illness Rating Scale (CIRS). The severity of dementia was evaluated by the Clinical Dementia Rating (CDR) score. Caregiver distress due to the behavioral problems of the patient was assessed by the Neuropsychiatric Inventory-Distress, a subscale of the NPI which evaluates stress caused by each behavioral disturbance of the patient, and by the Brief Symptom Inventory which evaluates anxiety and depression. Burden was evaluated by the CBI. Results: The CBI showed very high internal consistency (Cronbach's alpha value > 0.80). Factor analysis showed that the items clustered into four dimensions, and not five as originally proposed. Multiple regression analysis revealed that patients' behavioral disturbances and disability were the major predictors of the time-dependent burden; the psychophysical burden was explained mainly by caregiver anxiety and depression. Conclusions: The CBI proved to be an effective multidimensional tool for evaluating the impact of burden on many aspects of caregivers' lives.