Metabolic Risk Factors in Drug-Naive Patients With First-Episode Psychosis

Objective: Metabolic risk factors, such as obesity, as well as abnormalities in glucose and lipid metabolism, have been shown to have an increased prevalence in patients with schizophrenia, especially in those treated with antipsychotic medication. However, studies looking at these abnormalities in drug-naive patients have been few in number and have yielded mixed results. The aim of our study was to look at the prevalence of some of the cardiovascular risk factors, such as obesity and lipid and glucose abnormalities, in drug-naive patients with first-episode psychosis compared to healthy controls matched for age, gender, and ethnicity.

Method: One hundred sixty patients aged between 18 and 40 years who presented to the Early Psychosis Intervention Programme in Singapore with a diagnosis of first-episode psychosis according to the Structured Clinical Interview for DSM-IV Axis I Disorders-Patient Edition were assessed for their body mass index (BMI) and plasma levels of fasting glucose and lipids. The results of this assessment were compared to similar data from 200 controls matched for age, gender, and ethnicity, collected as part of an annual workplace health screening. The study was conducted from June 2002 to March 2005.

Results: There were significant differences in the mean baseline weight, BMI, and plasma levels of total and LDL cholesterol; all of these values were significantly higher in the controls compared to patients (p 3.4 mmol/L) as compared to patients (p < .005 and p = .01, respectively). However, patients compared to controls were significantly more likely to have diabetes (p = .007).

Conclusions: The link between diabetes and psychotic illness previously reported in relatives of patients with schizophrenia and in medication-naive patients implies a possible genetic link between schizophrenia and abnormal glucose metabolism. However, the finding of low prevalence of obesity and dyslipidemia at the onset of illness suggests that the increased frequency of these abnormalities in patients is an effect of their antipsychotic medication.