Long-term effects of rivastigmine in moderately severe Alzheimer's disease: does early initiation of therapy offer sustained benefits?

Abstract

Goals of the study included evaluating the long-term efficacy of rivastigmine in Alzheimer's disease (AD) patient categories stratified by baseline dementia severity, and post hoc investigation of particular benefits of early initiation of rivastigmine treatment in moderately severe AD. Both rivastigmine-treated groups (originally randomized to 1-4 or 6-12 mg/day) experienced significantly smaller declines in Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog) scores from baseline than the projected placebo group after 52 weeks. Patients receiving rivastigmine from Day 1 experienced significantly less decline compared with patients originally receiving placebo and then initiating rivastigmine treatment after a 6-month delay. Furthermore, cognitive benefits were more robust in patients with moderately severe disease compared with previous reports in mild to moderately severe AD. Findings suggest that early treatment with rivastigmine 6-12 mg/day is associated with sustained long-term cognitive benefits in patients with moderately severe AD. The results support the value of early treatment of AD patients, particularly those with moderately severe AD.