Increased serum brain-derived neurotrophic factor in male schizophrenic patients with metabolic syndrome

Increased prevalence of metabolic syndrome was found in patients with schizophrenia. Brain-derived neurotrophic factor (BDNF) was involved in energy metabolism and the pathophysiology of schizophrenia, but differently in males and females. We aimed to investigate the serum BDNF levels in patients with schizophrenia with and without metabolic syndrome. Patients with schizophrenia were recruited. Their demographic data were collected. Metabolic profiles and serum BDNF levels were measured. Clinical symptoms were evaluated with Positive and Negative Syndrome Scale. Metabolic syndrome was determined with the criteria provided by Ministry of Health and Welfare of Taiwan. Framingham Risk Score (FRS) for estimate of 10-year risk for coronary heart disease was provided by National Institutes of Health. Of the 81 participants, 40.7% had metabolic syndrome. Those with metabolic syndrome had higher FRS. Using analysis of covariance adjusted for age and body mass index, male patients with schizophrenia with metabolic syndrome had higher serum BDNF levels than those without (4.6 ± 4.7 vs 3.3 ± 3.8 ng/mL, P = .022). No statistical difference was found between female patients with and without metabolic syndrome. Significant differences of serum BDNF levels were found between male patients with schizophrenia with and without metabolic syndrome, but not in females. This finding suggested the gender difference behind the mechanism of BDNF in metabolic syndrome in schizophrenia.