IQ in childhood psychiatric attendees predicts outcome of later schizophrenia at 21 year follow-up

Objective: Preschizophrenic children who merit psychiatric referral are claimed to have a particularly malevolent illness when the psychosis develops later. The 21 years outcome of a sample of such children was investigated. Method: Fifty-one children who attended psychiatric services, and were later diagnosed as having schizophrenia, were followed up a mean of 21 years later. Baseline childhood demographic, clinical and putative aetiological characteristics were identified from the case notes. Follow-up assessment evaluated clinical symptoms, social functioning and service utilization. The predictive value of baseline factors on outcome was examined. Results: Outcome was poor, and seven (14%) of the subjects were deceased. Childhood IQ was strongly predictive of social outcome (F =5.1, P =0.01) and service utilization (F =5.2, P =0.01), but not clinical symptoms. No other factors predicted outcome. Conclusion: Low childhood IQ had an unfavourable impact on social outcome and service utilization once schizophrenia developed.