Phenotypic characteristics in metabolically obese but normal weight non-diabetic patients with schizophrenia.

BACKGROUND

A unique group of individuals termed metabolically obese but normal weight (MONW) has been identified in the general population. The present study examined phenotypic characteristics of MONW individuals in a sample of normal weight, non-diabetic patients with schizophrenia.

METHODS

Outpatients 19 to 75 years old diagnosed with schizophrenia or schizoaffective disorder participated in a multi-center, cross-sectional study. Those with normal weight (body-mass-index (BMI)<25 kg/m(2)) were included in the present analysis. Patients were further defined as MONW or metabolically nonobese based on a cut-off value of the homeostasis model assessment of insulin resistance (HOMA-IR = 1.86). Fasting blood samples were collected to determine levels of various metabolic parameters. In addition, lipoprotein subclass concentrations and sizes were analyzed using nuclear magnetic resonance (NMR) spectroscopy.

RESULTS

Seventeen MONW individuals and 17 metabolically nonobese individuals matched by BMI and gender were identified from a study sample of 206 patients with schizophrenia. There were no significant differences between the two groups on anthropometric measures (waist circumference and waist/hip ratio, ps>0.3). However, the MONW group had significantly higher levels of intermediate VLDL particle and Apolipoprotein B, and significantly lower levels of large HDL particle compared with the metabolically nonobese group (p = 0.012, p = 0.036 and p = 0.041 respectively).

CONCLUSION

The MONW individuals in non-diabetic schizophrenia patients seem to have an unfavorable metabolic profile and significant atherogenecity. Clinicians should be vigilant about the risk of cardiometabolic comorbidity even when the patient' body weight is normal.