Neuropsychiatric symptoms predict change in quality of life of Alzheimer disease patients: A two-year follow-up study

Aim: To examine the effect of neuropsychiatric symptoms on longitudinal changes in the quality of life (QOL) of patients with Alzheimer disease (AD). Methods: First, we investigated whether neuropsychiatric symptoms at baseline predict changes in the QOL of AD patients over time. Then we examined the associations between changes in neuropsychiatric symptoms and changes in QOL. QOL was assessed using the Japanese version of the Quality of Life-Alzheimer Disease (QOL-AD) scale and other clinical instruments [ the Mini-Mental State Examination, The Neuropsychiatry Inventory (NPI)] at baseline and again two years later in 96 AD patients among 140 AD patients at baseline. We performed a multiple regression analysis of the baseline QOL-AD score, NPI score (mood, psychosis, and euphoria factor), Mini-Mental State Examination score, and other clinical instrument variables (e. g. Activities-of-Daily-Living scores) to determine their contribution to the change in QOL-AD score. Results: While the total QOL-AD score based on the patients' responses did not change significantly, the total QOL-AD score derived from the caregivers' responses declined. Both the Activities-of-Daily-Living score and the mood factor of the NPI score predicted the change in the QOL-AD score as assessed by the caregivers' responses. In addition, there was a significant correlation between the changes in two factors of the NPI, i.e. the mood and psychosis factor, and the changes in the QOL-AD score based on the caregivers' responses. Conclusions: The presence of specific neuropsychiatric symptoms (mood and psychosis symptoms) was associated with changes in the QOL of AD patients during the follow-up period.