Quetiapine versus risperidone in elderly patients with behavioural and psychological symptoms of dementia: efficacy, safety and cognitive function.

OBJECTIVE

In this study we directly compared the efficacy and tolerability of the atypical antipsychotics quetiapine and risperidone in elderly patients with dementia and symptoms of disturbed perception, thought content, mood or behaviour (behavioural and psychological symptoms of dementia-BPSD).

METHODS

We conducted an 8-week, rater-blinded, randomised study of 72 outpatients (55-85 years) with BPSD (assessed by NPI baseline score), who received flexibly-dosed quetiapine (50-400 mg/day) or risperidone (0.5-2 mg/day). Primary efficacy measure: Neuropsychiatric Inventory (NPI) Parts 1 and 2; secondary efficacy measures: Clinical Global Impression (CGI), Cohen-Mansfield Agitation Inventory (CMAI), Mini-Mental State Examination (MMSE), Age-adjusted concentration test (AKT). Safety evaluations included the incidence of extrapyramidal symptoms (EPS) and adverse events (AEs).

RESULTS

Sixty-nine of 72 patients were evaluable for efficacy (72 were evaluated for safety), 4 patients discontinued (3 due to AEs: quetiapine 2, risperidone 1; 1 lost to follow-up). Sixty-five patients received quetiapine (n=34; mean dose 77+/-40 mg/day) or risperidone (n=31; mean dose 0.9+/-0.3 mg/day). There was no significant difference between treatments on NPI scores; within treatment groups, NPI scores decreased significantly from baseline to Week 8 (P<or=0.05 vs. baseline). Most patients (quetiapine arm 67.6%, risperidone arm 71.0%) experienced clinical improvement (CGI-Improvement scores); both agents reduced agitation (CMAI scores); and there was no cognitive impairment (MMSE and AKT scores). There were no significant differences between treatments in any safety measures, including EPS. Four patients experienced serious AEs (quetiapine arm 3; risperidone arm 1); none were considered treatment-related by the study investigator. There were no cerebrovascular AEs or deaths.

CONCLUSIONS

Quetiapine or risperidone, at low doses, were equally effective and generally well tolerated (including no cognitive impairment) in the treatment of BPSD in elderly patients.