The concept of dependence has been proposed as an integrative measure to assess the progression of Alzheimer's disease (AD).This study aimed to investigate the association of patient's dependence level with the caregiver burden within a general theoretical model that includes other well-established determinants.

Observational and cross-sectional multicenter study. The sample consisted of patients with AD recruited in outpatient consultation offices by a convenience sampling procedure stratified by dementia severity. Cognitive and functional status, behavioral disturbances, dependence level, medical comorbidities, and caregiver burden were assessed by using standardized instruments. A path analysis was used to test the hypothesized relationships between the caregiver burden and its determinants, including the level of dependence.

The sample consisted of 306 patients (33.3% mild, 35.9% moderate, 30.7% severe), the mean age was 78.5 years (SD = 7.8), and 66.2% were women. The model fit was acceptable and explained 29% of the caregiver burden variance. Primary stressors were the level of dependence and the distress related to behavioral disturbances. Caregiver's age, gender, and co-residence with the patient were the contextual factors related to caregiver burden. The job status of the caregiver was a significant secondary stressor, functional disability was indirectly associated with caregiver burden via dependence, and frequency of behavioral disturbances was indirectly associated with the caregiver burden via distress.

Dependence was, apart from behavioral disturbances, the most important primary stressor directly related to caregiver burden irrespective of the disease severity.