Planning for the optimal design of studies to personalize antipsychotic prescriptions in the post-CATIE era: the clinical and pharmacoepidemiological data suggest that pursuing the pharmacogenetics of metabolic syndrome complications (hypertension, diabetes mellitus and hyperlipidemia) may be a reasonable strategy.

The variability of individual responses reported by the CATIE study has raised awareness of the need to reconsider personalizing prescriptions of antipsychotic medications for the purpose of establishing the best antipsychotic for each individual patient. As atypical antipsychotics are widely prescribed for severe mental illnesses other than schizophrenia and side effects are largely independent from diagnosis, personalizing antipsychotic dosing may have important public health implications. This hypothesis article emphasizes that, whereas other psychiatric medications may cause weight gain, antipsychotics appear to have additional effects. Antipsychotics may have direct effects (not explained by obesity) on hypertension, diabetes mellitus and hyperlipidemia. The clinical and pharmacoepidemiological literature appears to suggest that (1) antipsychotics rarely increase blood pressure, with the probable exception of clozapine; (2) antipsychotics (particularly clozapine and olanzapine) may interfere with glucose metabolism in a (still unknown) direct way, independently of their effects on obesity; and (3) clozapine and olanzapine (and possibly quetiapine and low-potency typical antipsychotics) may directly cause hyperlipidemia, independently of their effects on obesity. This commentary focuses on the effect sizes and the time interval/event sequence of the direct influences of antipsychotics on blood pressure, glucose metabolism and lipid metabolism. Cross-sectional lipid studies may show antipsychotic effects. It is hypothesized that it may be easier to design studies focusing on these three aspects than to design pharmacogenetic studies focusing on antipsychotic-induced weight gain or metabolic syndrome, which require long-term follow-up.