Lack of Gender-Related Differences in Childhood-Onset Schizophrenia.

OBJECTIVE: Gender differences, including younger age of onset and greater premorbid deficits in men, have been reported in adult-onset schizophrenia. This study comprehensively evaluated gender differences in childhood-onset schizophrenia (COS), a rare variant of the disorder.

METHOD: Demographic, premorbid, clinical, familial, and cognitive characteristics, presence of chromosomal abnormalities, and brain magnetic resonance imaging cortical volumes were evaluated in 133 patients with COS. Cortical analyses included age- and gender-matched healthy volunteers (n = 124).

RESULTS: Males with COS (n = 72) had a slightly but significantly younger age of onset than females with COS (mean age 9.51 ± 2.28 versus 10.29 ± 1.63 years, t131 = 2.21, p = .03), higher verbal IQ scores (83.00 ± 15.97 versus 75.58 ± 15.10, t89 = 2.24, p = .03), and higher rates of comorbid pervasive developmental disorder (28.17% versus 6.90%, χ(2)1 = 9.54, p < .01) and attention-deficit/hyperactivity disorder (43.86% versus 21.43%, χ(2)1 = 5.40, p = .02). There were no significant gender differences across other demographic, IQ, or clinical measurements, frequency of chromosomal abnormalities, family clinical measurements, premorbid functioning, or in gender-by-disorder interactions for magnetic resonance imaging brain measurements.

CONCLUSION: The present comprehensive examination found few remarkable gender differences in COS. Although less striking than that seen in adult-onset schizophrenia, males with COS had a younger age of onset. Attention-deficit/hyperactivity disorder and pervasive developmental disorder rates were high in COS overall, suggesting greater neurodevelopmental vulnerability in COS. However, the gender ratios of these comorbidities in COS mirror those of the general populations, indicating that these gender differences might be unrelated to COS.