Treatment effects of rivastigmine on cognition, performance of daily living activities and behaviour in Alzheimer's disease in an outpatient geriatric setting

Abstract

We investigated rivastigmine effectiveness in 84 Alzheimer outpatients, with a special focus on behavioural problems. Cognition, activities in daily living (ADL) and behaviour were assessed during 30 months. Changes in test results between 6 months and baseline were compared with a historical control cohort of Alzheimer patients (n = 69) by performing t-tests and calculation of Cohen's d and standardised response mean (SRM). During 6 months, rivastigmine showed effect on cognition (p < 0.001, Cohen's d = 0.33, SRM = 0.78), ADL (p < 0.001, Cohen's d = -0.43, SRM = -0.54) and memory-related behaviour (p = 0.006, Cohen's d = -0.28, SRM = -0.28). Depressive behaviour worsened (p = 0.001, Cohen's d = 0.30, SRM = 0.37) and disruptive behaviour (p = 0.369, Cohen's d = -0.07, SRM = -0.09) was not effected by rivastigmine. During 30 months, a gradual decline was shown in most domains. Most RMBPC items showed stabilization during 30 months. Improvement on disruptive behaviour items and depression items was shown after 6 months of treatment in a large proportion of patients in whom behavioural problems were present at baseline. In conclusion, a huge discontinuation rate is experienced within the first half year of treatment. In the subpopulation of patients who continued rivastigmine for 6 months, it shows modest effectiveness on cognition, functionality and memory-associated behaviour compared with historical control patients. Unfortunately, disruptive behaviour is not altered by rivastigmine therapy, and depressive behaviour worsened slightly after initial treatment. During 30 months, rivastigmine showed stabilization on numerous behaviour items as measured by the RMBPC.