Cognitive deficits in several domains have been demonstrated in early-onset schizophrenia patients but their profile and relation to depressive symptoms and intelligence need further characterization. The purpose was to characterize the profile of cognitive deficits in chronic, early-onset schizophrenia patients, assess the potential associations with depressive symptom severity, and examine whether cognitive deficits within several domains reflect intelligence impairments. This study compared attention, visual-construction, aspects of visual and verbal memory, and executive functions in chronic, early-onset schizophrenia patients (mean age = 20.7 years) (N = 18) and healthy controls (N = 38). Schizophrenia diagnoses were established at the time of the patients' first clinical presentation during childhood or adolescence and were confirmed five years later. In the chronic phase of early-onset schizophrenia, significant deficits were observed in all specific cognitive functions. The profile of cognitive deficits was jagged, and visual-construction, attention, and one aspect of verbal memory (verbal stories recall) were differentially impaired. Deficits of visual recall, visual recognition, and executive functions were accounted for by deficits in intelligence, while this was not the case for deficits of verbal recall of stories or attention. No significant associations were observed between the severity of cognitive deficits and that of depressive symptoms. Chronic, early-onset schizophrenia is characterized by a broad and jagged profile of cognitive deficits. Deficits of attention and verbal recall of stories appear not to be accounted for by deficits in intelligence, and the severity of cognitive deficits seems independent from that of depressive symptoms.
Scandinavian Journal of Psychology, 2013, Vol 54, Issue 5, p. 363-70