Relapse risk after discontinuation of risperidone in Alzheimer's disease.

BACKGROUND: Among patients with Alzheimer's disease who have had a response to antipsychotic medication for psychosis or agitation-aggression, the risk of a recurrence of symptoms after discontinuation of the medication has not been established. METHODS: Patients with Alzheimer's disease and psychosis or agitation-aggression received open-label treatment with risperidone for 16 weeks. Those who had a response to risperidone therapy were then randomly assigned, in a double-blind fashion, to one of three regimens: continued risperidone therapy for 32 weeks (group 1), risperidone therapy for 16 weeks followed by placebo for 16 weeks (group 2), or placebo for 32 weeks (group 3). The primary outcome was the time to relapse of psychosis or agitation. RESULTS: A total of 180 patients received open-label risperidone (mean dose, 0.97 mg daily). The severity of psychosis and agitation were reduced, although there was a mild increase in extrapyramidal signs; 112 patients met the criteria for response to treatment, of whom 110 underwent randomization. In the first 16 weeks after randomization, the rate of relapse was higher in the group that received placebo than in the groups that received risperidone (60% [24 of 40 patients in group 3] vs. 33% [23 of 70 in groups 1 and 2]; P=0.004; hazard ratio with placebo, 1.94; 95% confidence interval [CI], 1.09 to 3.45; P=0.02). During the next 16 weeks, the rate of relapse was higher in the group that was switched from risperidone to placebo than in the group that continued to receive risperidone (48% [13 of 27 patients in group 2] vs. 15% [2 of 13 in group 1]; P=0.02; hazard ratio, 4.88; 95% CI, 1.08 to 21.98; P=0.02). The rates of adverse events and death after randomization did not differ significantly among the groups, although comparisons were based on small numbers of patients, especially during the final 16 weeks. CONCLUSIONS: In patients with Alzheimer's disease who had psychosis or agitation that had responded to risperidone therapy for 4 to 8 months, discontinuation of risperidone was associated with an increased risk of relapse. (Funded by the National Institutes of Health and others; ClinicalTrials.gov number, NCT00417482.).

The antipsychotic discontinuation in Alzheimer disease trial: clinical rationale and study design.

OBJECTIVES: : Research studies on the effects of discontinuing antipsychotic medications in patients with dementia have not identified specific target symptoms or response to antipsychotics prior to discontinuation. The Antipsychotic Discontinuation in Alzheimer Disease (ADAD) trial addresses these issues in a randomized, double-blind, placebo-controlled, multicenter risperidone treatment and discontinuation trial. In Phase A, AD patients with psychosis or agitation receive open treatment with risperidone for 16 weeks. Responders are randomized, double-blind, to one of three arms in Phase B: 1) continuation risperidone for the next 32 weeks, 2) risperidone for the next 16 weeks followed by placebo for 16 weeks, or 3) placebo for the next 32 weeks. METHODS: : Several design features provide unique strengths to this trial: identification of target symptoms and systematic open antipsychotic treatment with only responders randomized in the discontinuation trial, use of a single antipsychotic medication, two clinically relevant time-points for discontinuation to evaluate the impact of duration of treatment on relapse, exclusion of patients at increased risk of stroke, assessment of several affected symptom domains, and state-of-the-art approaches to assess relapse and handle dropout. CONCLUSIONS: : This study will provide clinically relevant data on the likelihood and time to relapse, and predictors of relapse, in patients switched from risperidone to placebo after response to risperidone treatment. Given the warnings about antipsychotic use in patients with dementia, studies of this type are essential to determine the optimal duration of treatment that confers the greatest benefit to risk ratio and to improve evidence-based treatment strategies.

Prediction of Relapse After Discontinuation of Antipsychotic Treatment in Alzheimer's Disease: The Role of Hallucinations.

OBJECTIVE: In Alzheimer's disease, antipsychotic medications are often used for a period, with relief of symptoms, and then discontinued, after which relapse may occur. The authors sought to determine which neuropsychiatric symptoms predict relapse. METHOD: In the Antipsychotic Discontinuation in Alzheimer's Disease trial, 180 patients with Alzheimer's disease and symptoms of agitation or psychosis were treated with risperidone for 16 weeks, after which patients who responded (N=110) were randomly assigned to continue risperidone for 32 weeks, to continue risperidone for 16 weeks followed by switch to placebo for 16 weeks, or to receive placebo for 32 weeks. As reported previously, discontinuation of risperidone was associated with a two- to fourfold increased risk of relapse over 16-32 weeks. In planned post hoc analyses, the authors examined associations between the 12 symptom domains in the Neuropsychiatric Inventory (NPI) and relapse in the first 16-week phase after randomization. RESULTS: Compared with patients with mild hallucinations or no hallucinations, patients with severe hallucinations as a presenting symptom at baseline had a higher likelihood of relapse (hazard ratio=2.96, 95% CI=1.52, 5.76). This effect was present for the subgroup with auditory hallucinations, but not the subgroup with visual hallucinations. Among patients with baseline hallucinations, 13 of 17 (76.5%) who discontinued risperidone relapsed, compared with 10 of 26 (38.5%) who continued risperidone (p<0.02). This group difference remained significant for severe (77.8%) compared with mild (36%) hallucinations. NPI domain scores after the initial open-treatment phase were not associated with relapse. CONCLUSIONS: Patients with severe baseline hallucinations were more likely to relapse after randomization, and the presence of baseline hallucinations was associated with a higher risk of relapse after discontinuation of risperidone compared with continued risperidone treatment. For patients with hallucinations, particularly auditory hallucinations, antipsychotic discontinuation should be approached cautiously because of high relapse risk.