PLASMA OXYTOCIN LEVELS IN AUTISTIC-CHILDREN

Background: Social impairments are central to the syndrome of autism. The neuropeptide oxytocin (OT) has been implicated in the regulation o f social behavior in animals but has not yet been examined in autistic subjects, Methods: To determine whether autistic children have abnorm alities in QT midday plasma samples from 29 autistic and 30 age-matche d normal children, all prepubertal, were analyzed by radioimmunoassay for levels of OT. Results: Despite individual variability and overlapp ing group distributions, the autistic group had significantly lower pl asma OT levels than the normal group. OT increased with age in the nor mal but not the autistic children. Elevated OT was associated with hig her scores on social and developmental measures for the normal childre n, but was associated with lower scores for the autistic children, The se relationships were strongest in a subset of autistic children ident ified as aloof Conclusions: Although making inferences to central OT f unctioning from peripheral measurement is difficult, the data suggest that OT abnormalities may exist in autism, and that more direct invest igation of central nervous system OT function is warranted. (C) 1998 S ociety of Biological Psychiatry.