In addition to cognitive decline, 30% to 40% of patients with Alzheimer's disease (AD) experience concomitant psychiatric and behavioral complications, such as hallucinations, delusions, and aggression. Atypical antipsychotics (AAs) are used to treat psychosis and aggressive behaviors in these patients; however, data regarding their early effects on cognition are conflicting. Based on a literature search, the cognitive effects of long-term treatment with AAs in outpatients with AD have not been studied.
The aim of this study was to describe and compare the rate of cognitive decline with longterm AA use in adult patients with AD receiving concomitant treatment with cholinesterase inhibitors.
This study was conducted at the Department of Neurology, The Ohio State University, Columbus, Ohio. Data were collected from the charts of adult outpatients who (1) received care at Memory Disorders Clinic, Columbus, Ohio, between April 2003 and June 2005; (2) were aged > or =55 years with a diagnosis of mild to severe definite or probable AD; (3) received an AA for > or =6 months or did not receive any AA; and (4) received a cholinesterase inhibitor during the entire evaluation period. Cognitive function, as measured using the Mini-Mental State Examination (MMSE), was compared between those who received AA treatment and those who did not. The end point was the rate of decline in cognitive function, defined as annualized change in mean MMSE score from baseline to the end of follow-up.
Ninety-two outpatients were included in the final analysis (67 women, 25 men; mean age, 72.4 years). Thirty-four patients received treatment with an AA for 6 > or =months (mean duration of treatment, 421 days) and 58 did not receive any AA treatment. Quetiapine (mean dose, 67 mg/d) was prescribed to 28 (82 %) of the patients receiving an AA. The AAs were prescribed for psychosis (15 [44%] patients), psychosis/agitation (11 [32%]), and agitation/aggression (8 [24%]). The baseline mean MMSE scores in patients receiving and not receiving an AA were 14.65 and 17.88, respectively (P = 0.021), with mean (SD) annual rates of cognitive decline of 3.03 (1.84) and 2.24 (1.27), respectively (P = NS).
The results from this retrospective study of data from a small, selected group of outpatients with AD did not find a significant difference in the rate of cognitive decline between those who received an AA for > or =6 months and those who did not.