Obstetric complications, psychiatric history, lower IQ linked to early-onset psychosis

Premorbid factors including obstetric complications, personal psychiatric background and IQ may help predict which patients are at increased risk for early-onset psychosis, according to study results.

“The neurodevelopmental hypothesis of psychosis posits that apart from genetic load, certain early developmental issues could result in an increased risk of psychosis,” Inmaculada Baeza, MD, PhD, of the department of child and adolescent psychiatry and psychology at the Hospital Clinic of Barcelona in Spain, and colleagues wrote in The Journal of Clinical Psychiatry. “In a recent systematic review and meta-analysis, a significant number of pre- and perinatal risk factors, such as congenital malformations, obstetric complications, birth in winter or early spring, maternal psychosis and maternal affective disorder were all associated with the onset of a psychotic disorder. Premorbid intelligence quotient has also been linked to age at onset of psychosis.”

The researchers sought to assess the variance in early-life characteristics among patients with early onset of psychotic disorders at younger than 18 years compared with adult onset of psychotic disorders, as well as to pinpoint earlier onset predictors.

They analyzed data of 278 patients with a first episode of psychosis between ages 7 and 35 years who participated in a multicenter prospective longitudinal study in Spain between Jan. 1, 2009, and Dec. 31, 2011. Participants received diagnoses for adult-onset psychosis (n = 224; mean age, 25.6 years; 65.6% men) via the Structured Clinical Interview for DSM-IV Axis I Disorders and for early-onset psychosis (n = 54; mean age, 16.1 years; 68.5% boys) via the Schedule for Affective Disorders and Schizophrenia for School-Aged Children. Data on participants’ early-stage factors, such as prenatal, perinatal and other premorbid factors, were obtained and compared between early and adult onset.

The researchers used univariate and multivariate logistic regression models to analyze the association between baseline variables and outcome. They also calculated the association or ORs for significant risk factors.

Results of univariate analysis showed significant between-group differences, with early-onset psychosis patients at increased risk for more frequent obstetric complications (P < .001), birth weight less than 2,500 g (P < .028), a background of any personal psychiatric disorder (P < .001), a previous diagnosis of ADHD (P = .001) and premorbid IQ lower than 85 (P < .001). Results of the multivariate model showed only obstetric complications (OR = 5.44), personal psychiatric background (OR = 4.05) and IQ lower than 85 (OR = 3.96) predicted an onset of first psychosis episode prior to age 18 years.

“Monitoring these early predictors of an [early-onset psychosis] can help clinicians intervene to prevent the transition to psychosis in at-risk individuals,” Baeza and colleagues wrote. “More research is needed in this key clinical field considering the significant repercussions of experiencing an [early-onset psychosis].”