Objective: To investigate the relation between health-related quality of life (QOL) rated by proxy and various characteristics of patients with mild-to-moderate Alzheimer's disease (AD) using European Quality of Life-5 Dimensions (EQ-5D).
Patients: We recruited 128 AD patients with a Clinical Dementia Rating (CDR) of 0.5 (very mild) to 2 (moderate) who were cognitively assessed using the Mini-Mental State examination, Alzheimer's Disease Assessment Scale, and Frontal Assessment Battery, and whose family caregivers underwent an interview with CDR, Neuropsychiatric Inventory (NPI) and the five-level version of the EQ-5D for the proxy rating.
Methods: We obtained Pearson's correlation coefficients between the EQ-5D utility score and each demographic, clinical, and cognitive measure. All measures with moderate or large effect sizes (0.3 or more of absolute value of the correlation coefficient) were included in a multiple correlation analysis.
Results: The CDR sum of boxes (CDR-SOB), NPI total score, and educational attainment showed moderate effect sizes in the single correlation analyses. The effect sizes of the cognitive measures were small. The multiple correlation analysis showed that the CDR-SOB and NPI total score independently contributed to the EQ-5D utility score.
Conclusion: Two independent factors, that is, overall severities of functional impairment and behavioral and psychological symptoms of dementia seemed to contribute to QOL in AD patients. (Received August 20, 2018; Accepted September 12, 2018; Published January 1, 2019).