Lack of Early Improvement with Antipsychotics is a Marker for Subsequent Nonresponse in Behavioral and Psychological Symptoms of Dementia: Analysis of CATIE-AD Data.

objectivePrediction of response or nonresponse to antipsychotics is especially important in patients with behavioral and psychological symptoms of dementia (BPSD) in whom antipsychotic exposure increases risks of death. This study examined whether the presence or absence of early improvement of BPSD with antipsychotics is associated with subsequent response or nonresponse.

methodsIn a post-hoc analysis of the Clinical Antipsychotic Trials of Intervention Effectiveness-Alzheimer's Disease (CATIE-AD) study (2001-2004) (clinicaltrials.gov; NCT00015548) in 45 U.S. sites, 245 subjects (olanzapine, N = 90; quetiapine, N = 81; risperidone, N = 74) with a DSM-IV diagnosis of dementia of the Alzheimer type who presented with a score of 1 or more in the Brief Psychiatric Rating Scale (BPRS) at baseline (phase I of CATIE-AD) were randomly assigned to treatment with olanzapine, quetiapine, risperidone, or placebo in a double-blind manner. Associations were examined between response at week 8 and demographic and clinical characteristics, including BPRS total score reduction at week 2, using logistic regression analyses. Prediction performance of binary classification (presence or absence) of improvement or no improvement at week 2 for response at week 8 was examined.

resultsBPRS total score reduction at week 2 (mean percentage score reduction: 12.6%) was significantly associated with response at week 8 (odds ratio: 1.18; 95% CI: 1.11-1.26). The 5% score reduction cut-off at week 2 showed the highest accuracy (0.71), with sensitivity, specificity, and positive and negative predictivevalues of 0.76, 0.65, 0.69, and 0.72, respectively.

conclusionLack of even a very small early improvement with antipsychotic treatment may be a marker of subsequent nonresponse in BPSD.