Trajectories of loneliness during childhood and adolescence: Predictors and health outcomes

► We tested whether there are distinct developmental trajectories of loneliness. ► Four trajectories were identified based on loneliness reported from 7 to 17 years. ► Risk factors taken at age 5 could predict membership of the high stable trajectory. ► Long-term loneliness was associated with health outcome at age 17. ► Our findings can inform preventive interventions that could be school-based.