Rivastigmine May Relieve Neuropsychiatric Symptoms
Rivastigmine May Relieve Neuropsychiatric Symptoms in Patients With Parkinson's Disease Dementia: Presented at AAGP
By Emma Hitt, PhD
HONOLULU -- March 8, 2009 -- Rivastigmine appears to relieve specific neuropsychiatric symptoms, euphoria/elation and irritability/lability, compared with placebo in patients with Parkinson's disease dementia (PDD), according to research findings presented here at the American Association for Geriatric Psychiatry (AAGP) 22nd Annual Meeting.
Lead author James E. Galvin, MD, Washington University School of Medicine, St. Louis, Missouri, and colleagues reported the findings here on March 6.
Rivastigmine, a cholinesterase inhibitor, is approved for the treatment of mild to moderate PDD. Previously, primary results of a large international 24-week randomised trial had shown a significantly improved treatment difference in total Neuropsychiatric Inventory (NPI)-10 score with rivastigmine versus placebo at week 24 (P = .02).
Patients were 50 years of age or older and had developed a mild to moderate dementia 2 or more years after being diagnosed with Parkinson's disease. The patients were randomised to receive rivastigmine capsules (3-12 mg/day) or placebo.
In the current analysis, Dr. Galvin and colleagues conducted a post hoc exploratory analysis of the primary trial data to determine differences between rivastigmine and placebo on NPI-12 individual-item scores. Specifically, the team wanted to determine whether rivastigmine could relieve neuropsychiatric symptoms associated with PDD, including depression, anxiety, psychosis, apathy, disorders of sleep and wakefulness, and agitation.
In patients experiencing neuropsychiatric symptoms at baseline (n = 458), rivastigmine was significantly superior to placebo in improving euphoria/elation (P = .04) and irritability/lability (P = .03), the researchers found.
Nonsignificant improvements with rivastigmine versus placebo were noted with delusions, hallucinations, agitation/aggression, anxiety, apathy/indifference, disinhibition, aberrant motor behaviour, and appetite/eating change. Rivastigmine was associated with nonsignificant worsening of depression/dysphoria and sleep/nighttime behaviour.
Of note, hallucinations were reported as an adverse event by only 4.7% of rivastigmine-treated patients compared with 9.5% of those receiving placebo (P = .04).
"Rivastigmine led to numerical improvements compared with placebo on most NPI items," the researchers concluded. "End-of-study differences in scores suggest a possible positive effect on delusions, hallucinations, and other NPI symptoms," they added.
Parkinson's disease dementia patients suffering from these symptoms may find relief with rivastigmine in terms of symptom resolution or reduction, the researchers suggested.
Funding for this study was provided by Novartis Pharmaceuticals Corporation.
[Presentation title: Rivastigmine in Patients With Parkinson's Disease Dementia: Analyses of NPI Items. Abstract NR 29]
