Memantine enhances autonomy in moderate to severe Alzheimer's disease.

Alzheimer's disease (AD) is the leading cause of dementia and its course renders patients functionally disabled. Memantine is the first drug to demonstrate a clinical benefit in the treatment of patients with moderately-severe to severe AD. Our objective was to illustrate the benefits of memantine on functional disability. We classified 252 patients from a randomised 28-week clinical trial of memantine vs placebo according to their Activities of Daily Living capabilities measured by the ADCS-ADLsev scale. The scale was divided into two sub-scores: basic and instrumental. The relevance of this classification was validated by comparing clinical and socio-demographic parameters between the different autonomy classes (autonomous and dependent). The effect of memantine was estimated by using a logistic regression model on the autonomy status of patients at week 28, controlling for confounding factors (Observed Cases analysis). Our results showed that dependent patients (n = 106) had significantly longer disease duration, poorer cognition, greater severity, more behavioural alterations and higher total societal costs compared with autonomous patients (n = 146). When controlling for autonomy and severity at baseline, memantine-treated patients were three times more likely [Odds Ratio (OR) = 3.03; 95% Confidence Intervals (CI) = (1.38, 6.66)] to remain autonomous after 28 weeks. Analysis of the Treated Per Protocol set and the use of Last Observation Carried Forward analyses confirmed this finding. Memantine enhances autonomy in patients with moderately-severe to severe AD by increasing the probability of their remaining autonomous, therefore delaying transition to the dependent stage.