The role of persistent psychotic experiences in inflammation in childhood and adulthood

Psychotic experiences (PEs) are associated with elevated blood markers of inflammation in both childhood and young adulthood. However, the relationship between persistent PEs, which are associated with the risk of mental disorders, and blood-based inflammatory markers, has not been previously investigated. To address this, we investigated two questions; the role of childhood inflammation and subsequent persistent PEs, and if persistence of PEs in youth is associated with adult inflammation. Secondary analysis of sex differences was conducted.

This study was conducted using the Avon Longitudinal Study of Parents and Children (ALSPAC; n = 7,913). Two inflammatory markers (C-reactive protein(CRP) and Interleukin-6) were assessed in the blood in childhood(age 9). CRP and soluble urokinase Plasminogen Activator Receptor(suPAR) were measured in the blood in adulthood (age 24). PE states (transient, recurring, persistent) were measured using the Psychosis-like symptoms interview three time points (age 12, 18, 24). Multinomial logistic and linear regressions were used for analyses. Sex stratified analyses were conducted. Missing data were imputed with multiple imputation by chained equations.

Persistence of PE in youth (age 11-24) was associated with elevated suPAR in adulthood, in a dose response (Transient:β = 0.11,95%CI[0.01,0.21]; Recurring:β = 0.20,95%CI[0.01,0.40]; Persistent: β = 0.53,95%CI[0.16,0.90]). When stratified by sex, the effect for suPAR occurred in women, but not men. Neither childhood inflammatory marker was associated with subsequent persistence of PEs.

This study suggests that persistence of PEs are associated with elevated chronic inflammation into adulthood, particularly in women. This finding suggest persistent PE could be an indicator of long-term poor physical health outcomes.