Objective: To study alcohol and drug addiction incidence in students exposed to the Dawson College shooting within the 18 months following the event, to identify the precursors of a psychoactive substance addiction development while considering the severity of event exposure, and to examine whether alcohol use, 18 months after the event, is related to any of the various posttraumatic stress disorder (PTSD) symptom groups.
Method: The population of this study was comprised of all the Dawson College students at the time of the event. Analyses were conducted with 854 students enrolled in the college at the time of the shooting.
Results: Five per cent of women and 7% of men showed, for the first time in their life, a problem with substance addiction following the shooting. In men, young age, lifetime suicidal ideation, and having seen the killer during the shooting are the main precursors of incident accident cases. None of the studied precursors were significant in women. Men and women were also different in terms of PTSD symptoms predicting alcohol use 18 months after the shooting.
Conclusion: The study highlights the importance of considering a person's sex when studying their psychoactive substance use following a trauma.