The impact of early multiple language exposure on hyperactivity/inattention symptom trajectories during childhood: Results from a UK birth cohort

Inattention and hyperactivity are common in childhood, yet their developmental trajectories vary widely. This study examines whether early multiple language exposure (MLE) is associated with hyperactivity/inattention symptoms using data from 13,175 participants in the UK Millennium Cohort Study. MLE, reported by parents at age 3, and symptoms, measured with the Strengths and Difficulties Questionnaire at ages 5, 7 and 11, were analysed through growth mixture modelling. Four trajectory classes were identified: low-stable, high-decreasing, low-increasing, and high-stable symptoms. Children with early MLE were more likely to belong to the high-decreasing than to either the low-increasing class or the high-stable class, even after adjusting for cognitive ability and socio-demographic factors. These findings indicate an association between early MLE and trajectory membership, after adjustment for cognitive ability and socio-demographic/family factors. Given the observational design and the coarse, parent-reported assessment of MLE, interpretations about mechanisms or applied implications should remain cautious.