Review of Atypical Antipsychotics and Weight Gain

Prescribing an antipsychotic for a patient with schizophrenia requires a risk-benefit analysis.Weight gain has become an issue recently as a result of reports that 2 of the atypical antipsychoticagents, clozapine and olanzapine, are associated with a higher risk than other drugs of causing excessiveweight gain. Some degree of weight gain may occur with any atypical antipsychotic agent, particularlyearly in treatment. A more important consideration is the long-term effects of the atypicalantipsychotic on body weight, since many of the patients in this population require chronic therapy.This is important because weight gain is an adverse effect that is associated with noncompliance andmedical problems. In this article, I review recent reports about the weight effects of different atypicalantipsychotic drugs. To provide accurate understanding of the effects of atypical antipsychotic agents,data analyses should include both short-term and long-term findings, the relationship of changes inbody weight to pretreatment body mass index (BMI), relationship to dose, both intent-to-treat andcomplete analyses, and presentation of both mean and median changes in weight. It is also importantto know whether the studies have been done in an inpatient or outpatient setting, since patients whoare institutionalized may be less likely to exhibit increases in body weight. Such complete informationand multidimensional analysis would minimize obfuscation about the true nature of a drug’s impacton body weight.