Cross-sectional examination of the association of co-occurring alcohol misuse and traumatic brain injury on mental health and conduct problems in adolescents in Ontario, Canada

Objective: This study describes the impact of traumatic brain injury (TBI) and hazardous drinking on mental health and behavioural issues among Ontario adolescents. In particular, we assessed the incremental co-occurrence of hazardous drinking with a history of TBI, in comparison to experiencing just one of these conditions. Methods: A cross-sectional subsample of 3130 Ontario adolescents attending grades 9-12, and aged 10-21 were surveyed in 2013 as a part of the Centre for Addiction and Mental Health's Ontario Student Drug Use and Health Survey. Recent (past year) and former (lifetime and excluding the last year) TBI were defined as trauma to the head that resulted in loss of consciousness for at least 5 min or overnight hospitalisation. Current hazardous drinking was derived using the Alcohol Use Disorders Identification Test (AUDIT). Results: An estimated 11.8% of Ontario adolescents (95% CI 10.1% to 13.8%) reported a history of former TBI and were not hazardous drinkers; 4.0% (95% CI 2.9% to 5.5%) reported recent TBI and were not hazardous drinkers; 13.7% (95% CI 12.3% to 15.3%) were hazardous drinkers who never had a TBI; 4.1% (95% CI 2.9% to 5.8%) had former TBI with cooccurring hazardous drinking; and 2.2% (95% CI 1.6% to 3.0%) had recent TBI with co-occurring hazardous drinking. Most odds increased significantly and were two to three times higher for reporting compromised mental health, violent and non-violent conduct behaviours, and reported victimisation for classifying as a hazardous drinker at the time of testing with cooccurring either former or recent TBI compared to classifying as not having either of these conditions. Adolescents classified as hazardous drinkers with former TBI had numerous and higher ORs for conduct behaviours than those with recent TBI. Conclusions: Results emphasise the strong interplay between TBI and hazardous drinking and point to the need for integrating prevention efforts to reduce these conditions and their co-occurrence among adolescents.