Emotionally detaching from a traumatic experience, a psychological defense known as dissociation, may play a key role in nudging some people with posttraumatic stress disorder (PTSD) toward alcohol-related problems, a new study suggests. A large minority of people with PTSD also have a substance use disorder (SUD), implying that using alcohol or drugs is a form of self-medication among traumatized people. Dissociation, a common symptom of PTSD, is a psychological escape from threatening situations that substitutes for physical escape; it can reflect particularly harmful early-life trauma and more severe PTSD. Previous research has linked dissociation with alcohol and substance use. Understanding the relevant pathway, or mechanism, could potentially inform and expand treatment options and effectiveness — a critical advance, since co-occurring PTSD and SUD come with a magnified risk of suicidality, functional impairment, and death. For the study in Alcoholism: Clinical & Experimental Research,Canadian researchers examined dissociation as a potentially influential link between PTSD severity and alcohol-related problems.

Investigators worked with 334 adults at an Ontario in-patient program for PTSD treatment. The sample was evenly split between women and men, who had an average age of 44. The participants filled out questionnaires on their mental health, alcohol use, demographics, along with self-report checklists assessing PTSD (including four symptom clusters), dissociative symptoms, alcohol-related problems, emotional dysregulation, and childhood adversity. The researchers used statistical analysis to explore the influence of dissociative symptoms on the relationship between PTSD and alcohol-related problems, and in the context of specific PTSD symptom clusters.

The analysis revealed that more severe PTSD was associated with heightened dissociative symptoms, and dissociation in turn was linked to greater alcohol-related problems. In a contrasting model, greater dissociative symptoms were associated with more severe PTSD, but more severe PTSD was not associated with alcohol-related problems. The two findings together indicate that dissociative symptoms are a key influence, or mediator, in the relationship between PTSD severity and alcohol-related problems. Analyses involving specific PTSD symptom clusters provided supporting evidence. Alterations in arousal (i.e., hypervigilance, sleep disturbance, etc.), intrusive thoughts and memories, and negative shifts in cognition and mood were associated with dissociative symptoms, which in turn were linked to alcohol-related problems.

The study is believed to be the first that reveals the unique role of dissociative symptoms in raising the risk for alcohol-related problems among some people with PTSD. It suggests that people with PTSD who experience heightened symptoms of dissociation are at increased risk of self-medicating with alcohol and other substances and may experience more severe alcohol-related problems than people whose PTSD does not involve dissociation. Targeting patients’ dissociative symptoms may be a helpful approach in treating PTSD and problematic drinking. The researchers recommend further examination of dissociation’s role over time, including comparing its influence during and in the aftermath of trauma.