Anxiety symptom trajectories across development: risk factors and outcomes

Background: Anxiety is one of the most common conditions affecting young people. The onset and course of symptoms are highly variable across development and if left untreated, can lead to poor outcomes. We modelled trajectories of anxiety symptoms from childhood to early adulthood and examined associated predictors and adult outcomes. Method: We analysed data from the Twins Early Development Study, a UK-based longitudinal twin cohort (N = 13,965). Anxiety symptoms were assessed using the Strengths and Difficulties Questionnaire from ages 4 to 26. Growth mixture modelling was used to identify anxiety symptom trajectories. We examined associations between trajectory class membership and genetic, early life family environment factors and child characteristics, as well as adult outcomes at age 26. Findings: We identified four anxiety symptom trajectories: Low Stable (n=9,440, 68%), Adolescent-Onset (n=2,486, 18%), Childhood-Limited (n=1,583, 11%) and Persistent (n=456, 3%). Neuroticism polygenic score, maternal depression, female sex, early conduct, and peer problems were associated with membership in all three of the smaller, higher severity, anxiety symptom classes. Female sex, conduct and peer problems distinguished these three classes from one another. The Childhood-Limited and Persistent classes were additionally associated with household chaos; Adolescent-Onset anxiety with general cognitive ability and polygenic scores for Major Depressive Disorder and Attention Deficit Hyperactivity Disorder; and Persistent anxiety with polygenic score for Anxiety Disorder. In terms of outcomes, Persistent and Adolescent-Onset trajectories were associated with poor clinical and life outcomes in early adulthood.Interpretation: The developmental course of anxiety is associated with polygenic risk for psychopathology, the early family environment, and child characteristics, with some associations differing between trajectory groups. Screening for high Neuroticism polygenic score, maternal depression, general cognitive ability, and conduct and peer problems may enable the early identification of those at risk of developing anxiety.