LAUSR

Abstract Background Childhood temperament has previously been shown to be associated with mood and anxiety disorders later in life. Studies have also suggested possible links between childhood temperament and later psychosis. Aim To investigate the association between childhood temperament and its individual component factors, measured at age 5, and later psychiatric disorders including psychosis. Methods Using a sample from a Finnish birth cohort (N=1014), we used logistic regression models to examine associations between maternal reported childhood temperament at age 5, and later psychiatric diagnoses, ascertained through linkage with the Finnish Hospital Discharge Register. Results Individuals with a childhood temperament rated as difficult at age 5 had almost 5-times the odds of developing a psychotic disorder in adulthood compared to those with a temperament rated as average by their mothers (OR = 4.91, 95% CI = 1.51 – 15.91). The individual temperament factors of approach withdrawal, adaptability and quality of mood were each independently associated with later psychotic disorder while different temperament components were associated with increased risk of mood disorders. Discussion Early childhood temperament could be used in combination with other early life indicators to identify those at greatest risk for the development of psychosis later in life, and to inform the implementation of early interventions such as parent-training programs and school-based interventions to support children in developing more adaptive behavioural and self-regulatory strategies. Additionally, intervening early in a child’s life to support more optimal temperament development, such as better adaptability to new stressful situations through specific skills training, could be a viable target for early intervention to reduce psychosis risk.