OFF-LABEL MEDICATIONS:

Memantine (Namenda / Ebixa) is FDA-approved for Alzheimer’s. Learn how it significantly improves memory and attention in Lewy Body Disease, Parkinson’s and various types of dementia.

An important study shows that performance on objective tests of attention and memory can be improved by memantine in two other major forms of dementia – Parkinson’s disease dementia and dementia with Lewy Bodies. The improvements detected were highly statistically reliable and of clinically relevant effect sizes; indicating that memantine can produce cognitive benefits in patients with these dementias which match those seen previously with anticholinesterases.

Memantine is FDA approved just for Alzheimer’s. Doctors may prescribe it “off-label”, if in their clinical judgment it may help their patient with Lewy Body dementia or Parkinson’s disease.

Both studies utilised the CDR System™, an automated cognitive test system, making a strong case for benefits for the increased sensitivity and specificity that such procedures bring to dementia research, when compared with the traditional tests which have been historically employed.

The results were part of a presentation at an Alzheimer’s Association International Conference.

The current consensus guidelines for diagnosis of dementia with Lewy Bodies (DLB) and Parkinson’s disease dementia (PDD) identify deficits to attention as core features in both conditions. ^(2,3). The present study evaluated the effects of memantine in DLB & PDD.

In related trials in both dementias, the CDR System detected significant benefits with rivastigmine on various aspects of attention ^(4-7).

METHODS

1. This was a parallel group, double-blind, placebo controlled, multicentre trial of memantine
2. 21 DLB and 30 PDD patients were assessed prior to dosing and again at 12 and 24 weeks
3. CDR System tests of attention (simple and choice reaction time) and word recognition (immediate and delayed) were administered.
4. The tasks were secondary measures and not included in the original study publication ⁽⁸⁾.

RESULTS

• Compared to placebo, memantine significantly improved choice reaction time (CRT) and the accuracy of both immediate and delayed word recognition (all p<0.02); with Cohen’s d effect sizes of between 0.56 and 0.57.
• The improvement in CRT was accompanied by a trend for improved accuracy on the task, and speed was numerically improved with memantine on the word recognition tasks.
• Beneficial effects of memantine were seen on 3 of the 4 tasks used in this study.

These are the first therapeutic improvements with memantine having clinically relevant effect sizes in either DLB or PDD on validated automated cognitive tests of attention and episodic recognition memory.
They directly support the improvement in the primary study outcome.
Every measure from every CDR System test moved in the direction of improvement with memantine.

The analysis models included a term for the interaction between type of dementia with effects of treatment, but none of these approached significance for any measure. Thus the improvements with memantine occurred in both DLB and PDD.