Antipsychotic Drugs for Alzheimer's?
Researchers Stress the Need to Weigh Drugs' Risks
Oct. 11, 2006 -- The antipsychotic drugs Zyprexa, Seroquel, and Risperdal may help some Alzheimer's patients, but their side effects should be carefully weighed, a new study shows.
The 36-week study, published in The New England Journal of Medicine, included 421 people with Alzheimer's-related psychosis, aggression, or agitation.
The patients were in their late 70s, on average.
The University of Southern California's Lon Schneider, MD, and colleagues randomly split the patients into four groups, giving each group a different drug.
One group received Zyprexa. Another group got Seroquel. A third group took Risperdal. For comparison, the fourth group got pills containing no medicine (placebo).
Drug doses were adjusted as needed.
The researchers tracked how long patients stayed on their assigned drug.
Eighty-two percent of the patients discontinued their assigned drug during the study.
Patients in all four groups stayed on their drugs (including the placebo) for a similar average amount of time: five to eight weeks, the study shows.
Between 16% and 24% of patients taking any of the antipsychotic drugs stopped taking those drugs due to adverse events -- such as sedation, tremors, or movement problems -- compared with 5% of those taking placebo.
The four groups also included similar percentages of patients who showed symptom improvements (26% to 32% of those taking antipsychotic drugs and 21% of the placebo group).
"Adverse effects offset advantages in the efficacy of atypical antipsychotic drugs for the treatment of psychosis, aggression, or agitation in patients with Alzheimer's diseaseAlzheimer's disease," the researchers write.
By "atypical antipsychotics," they mean newer antipsychotic drugs, which include those used in this study.
Full Results to Come
After discontinuing their assigned drug, patients were allowed to start taking other antipsychotic drugs or citalopram, an antidepressant.
The option to switch to another drug might have led some patients to discontinue their assigned drug, the researchers note.
The results posted in The New England Journal of Medicine are just the first phase of a five-year study. So there are more findings to come from the study's later phases.
"Although the differences among the groups may have been significant in a larger trial, our findings suggest that there is no large clinical benefit of treatment with atypical antipsychotic medications as compared with placebo," the researchers write.
Prescribing Antipsychotics After 'Deliberation'
"We thought overall the drugs would show their effectiveness," Schneider says in a University of Southern California news release.
"The answer is yes, they are somewhat effective, but overall the efficacy is offset by adverse events that resulted in discontinuing the medication," Schneider continues.
"It was a surprise, in that the expert opinion which drove this study was that these drugs are particularly useful in treating these difficult symptoms," Schneider says.
"The findings here look at the time to discontinuation for the antipsychotics versus the placebo, and that time difference reflects the overall effectiveness of the medication. By that measure, the medications were not better than placebo," he says.
"The results suggest that antipsychotic drugs should be prescribed only with some deliberation," Schneider says.