title: Similar frequency of abnormal correlation between serum leptin levels and BMI before and after olanzapine treatment in schizophrenia.
abstract: Melkersson proposed leptin dysregulation as a factor in the olanzapine-induced metabolic dysfunction. Their suggestion was based on the absence of the expected positive correlation between serum leptin levels and the BMI, and the loss of the sex-dependent difference in leptin levels, which are higher in women. Although subsequent studies did not confirm that proposal, few of them assessed basal leptin levels and corrected for body fat percentage. Along with these variables, we added a precise definition of participants out of the expected positive correlation in a large sample of schizophrenia patients. Sixty patients (26 women and 34 men) with severe schizophrenia undergoing chronic hospitalization and conventional antipsychotic treatment were switched to olanzapine (10-20 mg/day). We assessed at baseline, and at weeks 8 and 16 of treatment, the percentage of participants with abnormal correlation (out of the 95% confidence interval in the regression line) between leptin levels and the BMI, and the correlation between leptin and insulin, glucose, the insulin resistance index, c-reactive protein (CRP) and treatment response. Leptin levels were higher in women than in men (P<0.01). The positive correlation between leptin levels, BMI and percentage of fat were preserved. After olanzapine, 3.8% of women and 2.9-5.8% of men were out the 95% confidence interval, and the proportion was similar at baseline. Glucose, insulin, the insulin resistance index and the CRP levels significantly increased after olanzapine. The impact of olanzapine on leptin regulation appears discrete and limited to a small number of participants. Additional studies must clarify the features that render them to metabolic dysregulation.
authors.affiliation: Departments of Physiology, Los Andes University Medical School, Mérida, Venezuela. trinbap@yahoo.com
authors.forename: Trino
authors.initials: T
authors.lastname: Baptista
authors.forename: Adriana
authors.initials: A
authors.lastname: Dávila
authors.forename: Yamily
authors.initials: Y
authors.lastname: El Fakih
authors.forename: Euderruh
authors.initials: E
authors.lastname: Uzcátegui
authors.forename: Nairy N
authors.initials: NN
authors.lastname: Rangel
authors.forename: Yamile
authors.initials: Y
authors.lastname: Olivares
authors.forename: Tatiana
authors.initials: T
authors.lastname: Galeazzi
authors.forename: Doritza
authors.initials: D
authors.lastname: Vargas
authors.forename: Rocio
authors.initials: R
authors.lastname: Peña
authors.forename: David
authors.initials: D
authors.lastname: Marquina
authors.forename: Vanesa
authors.initials: V
authors.lastname: Villarroel
authors.forename: Luis
authors.initials: L
authors.lastname: Teneud
authors.forename: Serge
authors.initials: S
authors.lastname: Beaulieu
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000009:adverse effects* / Q000494:pharmacology / Q000627:therapeutic use*; D001569:Benzodiazepines / Q000009:adverse effects / Q000494:pharmacology / Q000627:therapeutic use; D001786:Blood Glucose / Q000187:drug effects; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000032:analysis; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood; D007333:Insulin Resistance; D020738:Leptin / Q000097:blood*; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D000077152:Olanzapine; D012559:Schizophrenia / Q000188:drug therapy*; D012737:Sex Factors; D015430:Weight Gain / Q000187:drug effects
chemical_list: D014150:Antipsychotic Agents; D001786:Blood Glucose; D007328:Insulin; D020738:Leptin; D001569:Benzodiazepines; D002097:C-Reactive Protein; D000077152:Olanzapine