Associations between Multiple Early Risk Factors and Cognitive Functioning at Time of Diagnosis in Children, Adolescents, and Adults with First-Episode Psychosis

BackgroundSchizophrenia is associated with widespread cognitive impairments. Several early risk factors for schizophrenia have been identified, and some studies suggest associations between these early risk factors and cognition, yet the literature is sparse in psychosis. MethodsClinical cohorts of child/adolescent and adult patients with first-episode psychosis (FEP) and healthy controls (HC) were linked with register-based information (N=276). Gestational age, Apgar scores, birth weight and length, parental age, and season of birth were extracted from the Danish medical birth registry. Cognition was assessed at time of diagnosis using BACS, CANTAB, and WAIS-III/WISC-IV. Missing data was imputed using MICE. Canonical correlation analysis (CCA) was used to examine patterns of associations. Post hoc analyses explored group differences according to diagnosis, age, and sex. ResultsCCA resulted in two significant patterns of associations. CCA1 was stable across imputations (r=0.44, p=.036, pmin= .017, pmax= .055), and constituted by a risk profile of lower maternal age, lower birth length, being small for gestational age, and lower birth weight and a cognitive profile of lower estimated IQ and poorer working memory, mental flexibility, processing speed, verbal fluency, and motor latency. The pattern was more expressed in FEP compared to HC and in adults compared to children. CCA2 was more unstable across imputations (r=0.38, p=.033, pmin=.003, pmax=.168) and constituted by a broad pattern of minor loadings. ConclusionCognitive functioning later in life is associated with multiple early risk factors, underscoring the complexity of developmental processes and the importance of the early developmental context in shaping cognitive trajectories.