Prevalence of metabolic syndrome among patients with schizophrenia in Japan.

Aims: In an Asian population, the criteria for metabolic syndrome (MetS) are different from those for Western populations. The aim of this study was to assess the MetS prevalence among patients with schizophrenia or schizoaffective disorder in Japan.

Methods: We recruited patients (n=1186), aged 54.8±14.8 (mean±SD) years old with the DSM-IV diagnosis of schizophrenia or schizoaffective disorder who were admitted to seven psychiatric hospitals using a cross-sectional design. MetS prevalence was assessed by three different definitions, including the adapted National Cholesterol Education Program Adult Treatment Panel (ATP III-A). Comparative analysis was performed with schizophrenic subjects and 886 participants from the Iwaki Health Promotion Project 2008 as representative of general population.

Results: The overall MetS prevalence based on the ATP III-A definition was 27.5%, with 29.8% in male and 25.3% in female patients. In a logistic regression model with age and body mass index as covariates, being schizophrenic was a significant independent factor (odds ratio=2.00 for males, 2.13 for females) in the development of MetS under the ATP III-A definition. The difference of MetS prevalence between patients and the general population was observed for those under 60 years of age.

Conclusions: Patients with schizophrenia or schizoaffective disorder in Japan had high prevalence of MetS compared to the general population, and was most apparent for those under 60 years of age. The MetS in schizophrenic patients should be carefully monitored to minimize the risks.