Glucose abnormalities in the siblings of people with schizophrenia

Background: Some studies suggest that schizophrenia may be associated with an increased risk of diabetes, independently of antipsychotic medications and other confounding factors. Previous studies have also suggested that there is an increased prevalence of diabetes in the relatives of schizophrenia probands. Method: First-degree siblings of schizophrenia probands (N=6) and control subjects N=12) were administered a glucose tolerance test. Subjects were matched for gender, age, body mass index, neighborhood of residence, socio-economic status and smoking habits. Results: The siblings of schizophrenia probands had a significantly increased two-hour mean glucose concentration compared to the control subjects (respective means [SD] were 100.5 mg/dL [27.7] vs. 78.0 [12.3] ; p <0.03). Baseline glucose concentrations did not differ. Conclusions: Although confirmation with larger samples is needed, these results and other studies suggest that diabetes may share familial risk factors with schizophrenia. (C) 2008 Published by Elsevier B.V.