A Path Analysis of Dependence and Quality of Life in Alzheimer’s Disease

Abstract

Objective: To determine the direct and indirect relationships of cognitive, functional, and behavioral factors and other medical comorbidities with the quality of life (QoL) of patients with Alzheimer’s disease (AD) according to the theoretical model of dependence. Methods: Observational and cross-sectional study. Cognitive and functional status, behavior, dependence, medical comorbidities, and QoL were assessed by using standardized instruments. A path analysis was used to model the direct and indirect relationships among clinical indicators according to the theoretically based model of dependence. Results: The sample consisted of 343 patients with AD (32.1% mild, 36.7% moderate, and 31.2% severe). Medical comorbidities, disease severity, and dependence level had a direct relationship with QoL. The functional disability and the behavior disturbances were indirectly related to QoL via dependence level, and the cognitive impairment was indirectly related to QoL via severity level. Conclusion: Direct and indirect effects exist between clinical indicators, dependence, and QoL.