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Unravelling the complexities of trauma in people with substance use problems

12 December 2019
Trauma and substance use in treatment

Logan Harvey, a PhD candidate at the University of Sydney’s Matilda Centre, is exploring the relationship between Complex Post-Traumatic Stress Disorder and substance use.

Logan Harvey

Logan Harvey is looking at how trauma and substance use fit together.

Complex Post-Traumatic Stress Disorder (C-PTSD), a new diagnostic category added to the International Classification of Diseases (ICD-11) in 2018, marks a major development for those experiencing trauma-related mental health problems. This new diagnosis classifies the broad array of experiences and treatment needs of people who have experienced trauma and provides a formal diagnosis to complement the existing Post Traumatic Stress Disorder (PTSD) diagnosis. This month we spoke to Logan Harvey, a PhD candidate at the University of Sydney’s Matilda Centre, who is exploring the relationship between C-PTSD and substance use.

Who do you think will be most impacted by the new diagnosis of C-PTSD?

In my work as a Clinical Psychologist I speak daily with people struggling with substance use issues and the legacy of traumatic experiences. Often, the symptoms people report don’t necessarily reflect the classic PTSD symptom profile, and as a result don’t fit well within the available treatments.

This new diagnosis is particularly relevant in substance use treatment, because people with substance use problems are significantly more likely to have experienced traumatic events than the general population. Rates of childhood trauma, such as abuse and neglect are extremely high, as are rates of interpersonal violence, and as a result, prevalence rates of PTSD are also higher.

Trauma and related symptoms can greatly impact how a person might reduce or stop using a substance and can have a profound impact on an individual’s pathway through treatment and recovery.

What will your PhD add to trauma-related research?

My PhD is focusing on the complexities of trauma, with a goal of better understanding the way different types of traumatic experiences and different symptoms can impact a person’s substance use problems and treatment.  I’m hoping to show that people who have experienced trauma can have very diverse needs, and that our treatment services need to take this into account.

How will you conduct your research?

The Trauma & Substance Use in Treatment (TASIT) study is a joint project between the Western Sydney Local Health District Drug Health Service and the Matilda Centre. The TASIT study is currently recruiting a cohort of people receiving substance use treatment, and will explore how their traumatic experiences, trauma-related symptoms, and substance use interact, as well as how this can impact on treatment. In particular, the TASIT project will help examine how symptoms of C-PTSD can impact on substance use treatment.

The TASIT study will be one of the first studies in the world to explore this new diagnosis in a substance use treatment setting. It is hoped that this project will assist treatment providers to better understand which types of trauma and trauma symptoms might be particularly important to assess and incorporate into substance use treatment programs. We know that the way people experience and cope with trauma is very specific to each individual, so it makes sense that there might be a large variety of different symptoms and coping strategies people develop. If we can better understand this, we can help sharpen our treatment approaches to better suit the needs of people in the community.

To complement this work, I am also coordinating a chart review study which will examine treatment records to explore how existing clinical processes assess and treat trauma related problems. This will provide important information about how clinicians in substance use treatment settings describe and document trauma related problems, and importantly which types of traumatic experiences are more often discussed during substance use treatment. It will also provide important information about how different disciplines and clinicians integrate trauma-focused treatment into their clinical work.

Logan’s PhD is supervised by Associate Professor Katherine Mills, Associate Professor Tim Slade, and Dr Christina Marel at the Matilda Centre. The TASIT study is a collaboration with psychology and counselling clinicians working in the Western Sydney Local Health District Drug Health service.

For further information about The TASIT Study contact Logan Harvey via email at

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