Psychotic-like experiences in children born very preterm: evidence from clinical and population-based cohorts

Background and aim: The research explores the link between very preterm birth (VPT; under 32 weeks gestation) and the risk of later psychiatric disorders, specifically psychosis. Early subclinical signs of psychosis, known as psychotic-like experiences (PLEs), may manifest in childhood. The study aimed to examine PLEs in children from a clinical cohort vs. full-term (FT) controls and replicate findings in an independent population-based cohort.

Methods: The primary analyses were conducted in the Brain, Immunity and Psychopathology (BIPP) study, which included 197 VPT children recruited through Neonatal Intensive Care Units and 72 FT controls evaluated at an average age of 10.50±1.77 years. The researchers examined between-group differences in PLEs using the Prodromal Questionnaire-Brief Child Version (PQ-BC), which measured frequency and distress-related scores for different domains (unusual thought content, perceptual abnormalities, disorganised speech).

Regression models evaluated the associations between birth status (VPT vs. control) and PQ-BC scores, adjusting for age, sex, and socio-economic status. Secondary models also adjusted for cognitive ability and broader psychopathology. The researchers conducted pooled analyses to investigate cohort effects and cohort-by-group status interactions.

Results: In the BIPP study, VPT birth was associated with higher PQ-BC total scores (β=1.61, p=0.004) and distress scores (β=0.78, p=0.039), with the strongest associations seen in perceptual abnormalities. These associations remained significant after adjusting for cognitive ability and broader psychopathology, particularly for perceptual abnormalities. In the ABCD study, VPT birth was not significantly associated with global or domain-specific PQ-BC outcomes.

Discussion: The findings suggest that VPT birth increases vulnerability to PLEs in childhood, especially in the perceptual abnormalities domain. However, the lack of clear replication in the ABCD population-based cohort may be due to differences in the composition of its VPT subgroup, which may not fully represent the typical VPT individuals seen in clinical cohorts.