Bodyweight gain associated with atypical antipsychotics: epidemiology and therapeutic implications

Atypical antipsychotic medications are associated with different adverse effects and efficacy profiles compared with conventional antipsychotics (i.e. less extrapyramidal symptoms, improved-efficacy against negative symptoms and cognitive deficits, and most often a greater ability to improve patients' quality of life). However, the atypical antipsychotics may be associated with clinically significant bodyweight gain, increasing the risk of medical comorbidity, including diabetes mellitus, hypertension, cardiovascular disease and hyperlipidaemia. This literature review assesses the various bodyweight gain liabilities associated with atypical antipsychotics, as well as the effects of bodyweight gain on quality of life. The issue of prevention and management of this often neglected adverse effect is also examined. Most studies reviewed indicate that clozapine and olanzapine are associated with more bodyweight gain than the other atypical antipsychotics. There are potential factors that place certain patients at greater risk for bodyweight gain, including low pretreatment body mass index, young age and being of female gender. Furthermore, bodyweight gain associated with the use of atypical antipsychotics has been reported to be associated with clinical improvement, although this has not been substantiated widely. It is unclear whether increased medical comorbidity, including diabetes mellitus, coronary artery disease and/or elevated triglyceride levels, is secondary to the bodyweight gain associated with atypical antipsychotics, or the result of the agents themselves. A patient's quality of life may be greatly affected by excessive bodyweight gain; either by increased comorbid medical illness, an increased relapse rate associated with noncompliance, or the social stigma associated with being obese. However, most studies reveal that treatment with atypical antipsychotic medications is associated with improved quality of life compared with that achieved with conventional antipsychotic medications. Because bodyweight is an important health risk associated with atypical antipsychotics, prevention and effective management of bodyweight are paramount in preventing comorbid medical illness, relapse and possible noncompliance.