Serum levels of desacyl ghrelin in patients with schizophrenia on clozapine monotherapy

Aim Desacyl ghrelin is a hormone that might be a functional inhibitor of ghrelin, a potent hunger-stimulating peptide. Methods We determined fasting serum desacyl ghrelin levels in 24 subjects with schizophrenia on clozapine monotherapy and 24 healthy, age- and sex-matched controls. Biochemical and anthropometric measurements were combined with body composition determined using bioelectric impedance analysis. Results There were no differences in desacyl ghrelin levels between patients taking clozapine and the control group (272.09 ± 137.96 vs 259.62 ± 140.91 pg/mL, z = 0.17, P = 0.87). In the clozapine group, there were no differences between men and women for ghrelin levels (246.66 ± 123.17 vs 295.39 ± 151.77 pg/mL, z = −0.98, P = 0.32). In the clozapine group, fasting serum levels of ghrelin negatively correlated with waist-to-hip ratio (WHR) (r = −0.45, P = 0.03) and ionized calcium (r = −0.45, P = 0.03). Levels of ghrelin were lower in patients with WHR above World Health Organization-defined cut-off points (246.84 ± 114.34 [Q1 = 152.18, Q2 = 220.92, Q3 = 327.85] vs 400.30 ± 123.36 [Q1 = 283.73, Q2 = 414.03, Q3 = 485.8] pg/mL, z = 2.52, P = 0.01). In the clozapine group, there were no correlation with age, height, weight, body mass index, abdominal circumference, waist circumference, hip circumference, WHR, blood pressure, total cholesterol, high-density lipoproteins, low-density lipoproteins, triglycerides, uric acid, homocysteine, glucose, insulin, clozapine dose, duration of treatment with antipsychotics, duration of treatment with clozapine, total fat, target fat, basal metabolic rate, target weight, lean weight, body water, homoeostasis model assessment of insulin resistance (HOMA) 1-IR, HOMA2-IR and quantitative insulin sensitivity check index. Conclusion Based on our results, we cannot conclude that treatment with clozapine affects levels of desacyl ghrelin. Also, in our study population we did not confirm previously described associations between desacyl ghrelin and various metabolic parameters.