Executive Function and Externalizing Traits in Early and Late Onset Substance Use

Introduction: Early substance use during this sensitive window likely disrupts maturation processes, resulting in persistent impairments in cognitive and behavioural regulation. Aim: The present study aims to assess executive function and externalizing traits among individuals with early-onset and late-onset substance use. Methods: The study is a cross-sectional study conducted at the inpatient psychiatry (de-addiction) ward of the Government Mental Health Hospital, Visakhapatnam, Andhra Pradesh, India, from October to December 2025. Sixty individuals aged 18 to 45 with ICD-11 diagnosed substance use disorder and abstinent for a minimum one week were recruited using purposive sampling. Executive function was measured using the Brown Executive Function/Attention Scale. Aggressive tendencies were measured using the Buss–Perry Aggression Questionnaire (BPAQ). Results: Upon analysis of the composite T-score for all the individuals irrespective of the groups, 43 (71.7%) were found to have markedly atypical executive functioning, while 17 (28.3%) showed moderately atypical executive functioning, indicating that most individuals demonstrated significant impairment in executive functions. This indicates that substance use itself predispose to significant problems in executive function. The study also found that, higher executive dysfunction was associated with increased impulsivity and aggression in study groups. Conclusions: Early identification and intervention targeting cognitive and behavioral dysregulation are critical to mitigating the enduring burden of adolescent substance dependence. Key words: Substance use, Executive function, Externalizing traits, Buss–Perry Aggression Questionnaire, T-score.