Interleukin-2 levels in chronic schizophrenia patients

INTRODUCTION: Most research in interleukin activity in schizophrenia has been in Caucasian populations. We examined interleukin-2 (IL-2) levels and their relation to the duration of the illness, psychopathology and treatment effects, in chronic schizophrenia patients of Asian origin.

MATERIALS AND METHODS: Thirty chronic schizophrenia patients were recruited for the study and their demographic data and medication dosage were noted. Symptom severity was scored on the Positive And Negative Syndrome scale for Schizophrenia (PANSS) and blood sampling done. Ten healthy Chinese males were recruited as controls. Phytohaemagglutinin-stimulated production of serum levels of IL-2 were measured by enzyme-linked immunosorbent assay.

RESULTS: IL-2 levels (1327 +/- 596.2) of all 30 patients were significantly lower than that of the Chinese controls (2420 +/- 342.5). This effect was noted throughout the entire duration of the illness. Ethnic and age differences in IL-2 levels were not found. There was, however, a negative correlation with the duration of the illness and a positive correlation with the dosage of medication.

CONCLUSIONS: The results of this study of a population of mostly Chinese patients with schizophrenia replicate an important finding. Data such as this has not been reported previously on Asians of this racial group.