Objective: The objective of this study was to conduct exploratory analyses of data pertaining to the efficacy of donepezil treatment of patients with severe behavioral disturbances. Preliminary studies suggest that cholinesterase inhibitors, including donepezil, may reduce behavioral disturbances in patients with Alzheimer disease (AD). Most patients included in clinical trials have had low levels of psychopathology at baseline, and the effect of cholinesterase inhibitors on patients with more severe behavioral disturbances is unknown. The authors report the effects of donepezil on behavioral disturbances in patients with relatively severe psychopathology at baseline.
Methods: This is a hypothesis-driven secondary analysis of a three-phase study involving donepezil and sertraline. In phase 1, psychotropic agents were withdrawn; in phase 2, patients were treated in an open-label fashion with donepezil for 8 weeks; and in phase 3, patients on donepezil were randomized to receive placebo or sertraline for an additional 12 weeks. The data set analyzed is comprised of the patient population treated with donepezil (without sertraline) for 20 weeks. One hundred twenty patients were included in the analyses. Mean age was 76 years, average Mini-Mental State Examination Score was 18, and mean Neuropsychiatric Inventory (NPI) total score was 30. Primary efficacy assessments were the NPI, the Clinical Global Impression-Improvement, and the Clinical Global Impression-Severity scales. Secondary measures included the Behavioral Pathology in Alzheimer's Disease Rating Scale, The Hamilton Depression Rating Scale, and the Alzheimer's Disease Functional Assessment and Change Scale.
Results: Excellent concurrent validity was noted between the NPI and the Behavioral Pathology in Alzheimer's Disease Rating Scale. The total score of the NPI was significantly reduced over the 20 weeks of therapy with donepezil. Sixty-two percent of patients had at least a 30% reduction in the total NPI score (significantly greater than the number with no meaningful response). Likewise, more patients had total or partial resolution of depression and delusions than those who had no meaningful change. Factor analysis of baseline NPI data revealed five factors, including a psychosis factor, an agitation factor, mood factor, frontal lobe function factor, and appetite and eating disorders factor. Clinically meaningful treatment effect sizes were notable for the delusion factor (0.340) and the mood factor (0.39). There were significant correlations between the Clinical Global Impression-Improvement and reductions in mood and agitation scores.
Conclusion: The results of these analyses suggest that donepezil reduces behavioral symptoms, particularly mood disturbances and delusions, in patients with AD with relatively severe psychopathology.