Increased cardiovascular risk with second-generation antipsychotic agent switches.

OBJECTIVE: To model the risk of long-term, adverse cardiovascular events after switching from one second-generation antipsychotic medication (SGA) to another in patients with schizophrenia or schizoaffective disorder. DATA SOURCES: PubMed from 1985 to 2004 using the search terms atypical antipsychotics, obesity, weight, diabetes mellitus, dyslipidemia, hypercholesterolemia, lipids, second generation antipsychotics, antipsychotic agents, schizophrenia, metabolic syndrome, cardiovascular disease, and cardiovascular risk factors. STUDY SELECTION: By the authors. DATA EXTRACTION: By the authors. DATA SYNTHESIS: The selection of an SGA for an individual patient should be primarily based upon its therapeutic effectiveness. However, when two medications are clinically equivalent with respect to treatment outcomes, other important consequences of the medication choice should be considered. Depending upon the type of SGA switch, the risk of an adverse cardiovascular event may be lower, as when olanzapine is switched to risperidone, or may increase by as much as 33%, as when risperidone is switched to olanzapine or clozapine. CONCLUSION: Cardiovascular risk likely differs depending upon SGA choice, but limited data make it difficult to predict the metabolic changes associated with switching. Prospective controlled studies are needed to describe the cardiovascular consequences of switching among the antipsychotic agents so that evidence-based strategies can be developed for selection of the optimal SGA.