Effects of long-term treatment with antipsychotics on serum leptin levels

Background Abnormal regulation of the adipocyte-derived hormone leptin could play a role in body weight gain induced by antipsychotics. Aims To study the effects of long-term antipsychotic treatment on leptin levels in patients with schizophrenia. Method Serum leptin levels were determined in 59 out-patients with chronic schizophrenia and in the same number of healthy subjects controlled by gender, age and body mass index. Results Leptin levels did not differ between patients and controls. Leptin levels in patients with schizophrenia correlated with weight gain, even after controlling for current weight, but did not show any association with clinical variables. Antipsychotic class tended to exert different effects over leptin levels (among atypicals, olanzapine induced a greater increase). Conclusions Elevation of leptin levels induced by chronic antipsychotic treatment can be attributed to weight gain, but other mechanisms could be involved.