The efficacy and safety of risperidone in the treatment of psychosis of Alzheimer's disease and mixed dementia: a meta-analysis of 4 placebo-controlled clinical trials

Background Dementia typically includes behavioral and psychological symptoms of dementia (BPSD) as well as cognitive decline. Psychosis of Alzheimer's disease (AD) is a specific component of AD, characterized by delusions, misidentifications, and hallucinations. Methods This study is a meta-analysis of patients with psychosis of AD from four large placebo-controlled clinical trials of risperidone in dementia. Three trials included patients diagnosed with heterogeneous symptoms of BPSD (those with psychosis of AD were included in this analysis), while one trial included only those diagnosed with psychosis of AD. Efficacy was measured using the Behavioral Pathology in Alzheimer's Disease (BEHAVE-AD) Psychosis subscale and Clinical Global Impression (CGI). Results Primary analyses in the psychosis of AD population demonstrated that risperidone significantly improved scores on the BEHAVE-AD Psychosis subscale and CGI scale compared with placebo. Secondary analyses demonstrated that patients with more severe symptoms showed a more pronounced response to treatment with risperidone compared with placebo than those patients with less severe symptoms. Extrapyramidal symptoms and somnolence were more frequent with risperidone than placebo (p = 0.04). Cerebrovascular adverse events and all-cause mortality were observed more frequently, although not statistically significantly, with risperidone versus placebo. Conclusions This meta-analysis of psychosis of AD showed improvement in psychotic symptoms and general clinical improvement in patients with psychosis of AD treated with risperidone compared with placebo. The benefits of treatment were most significant in patients with severe symptoms. The safety profile of risperidone in this psychosis of AD population was similar to the more general BPSD population. Copyright (c) 2007 John Wiley & Sons, Ltd.