Some people who experience traumatic events face subsequent mental health challenges. The most well-studied of these is posttraumatic stress disorder (PTSD) (Kessler et al., 2017), but over the last decade, there has been growing awareness that trauma-related psychopathology extends beyond PTSD. For example, it is now well-known that people with PTSD often have co-occurring depression and/or substance use disorders (Brady et al., 2000; Galatzer-Levy et al., 2013; Kachadourian et al., 2014). There is also increasing evidence that a wider range of psychiatric conditions can co-occur with PTSD (Lewis et al., 2019), and that some people only develop mental health disorders other than PTSD following trauma (e.g., phobias and depression) (Asselman et al., 2018).
Research on the full range of psychiatric disorders that can follow trauma is limited. This is in part because it is not practical to obtain data on all possible psychiatric disorders in most survey-based and clinical studies. Not only would this require lengthy assessments, but very large samples would be needed in order to observe rare outcomes like psychosis.
This is where national medical registries can help. Most national medical registries, including those in Denmark, contain comprehensive information on medical diagnoses in the form of standardized codes assigned during medical visits. While this is a rich source of medical data, traumatic experiences are not directly recorded in medical registries, seemingly prohibiting research on the effects of trauma using these data.
Our study introduced a new way of identifying traumatic experiences using medical registry data, based on the Diagnostic & Statistical Manual’s definition of a traumatic experience: an event involving indirect or direct exposure to death or serious injury, either actual or threatened (American Psychiatric Association, 2013). We reviewed medical and accident codes recorded in Danish national registries to identify experiences aligning with this definition, and to identify people who had those experiences.
For example, we used codes representing exposure to fire and treatment for burns to identify people who likely experienced a fire or explosion, codes representing complications of labor and delivery (e.g., stillbirths) to identify pregnancy-related trauma, and codes representing treatment for accident-related injuries to identify involvement in a serious accident. Other types of traumatic events captured included traumatic brain injury, assault, suicidal death of a close relative, and exposure to a toxic substance/medical complication.
After identifying all Danish residents believed to have experienced one or more of these traumatic events, we assessed how common 11 categories of psychiatric disorders were following an individual’s first traumatic event. We also assessed whether each disorder was more common among those who experienced trauma than among people who experienced a non-traumatic stressor (specifically, the non-suicidal death of a close family member).
As expected based on existing studies (Brady et al., 2000; Galatzer-Levy et al., 2013; Kachadourian et al., 2014), we found depressive disorders, substance use disorders, and stress disorders (including PTSD) were the most common types of psychiatric disorders following trauma, developing in 4%, 3%, and 2.5% of participants, respectively. However, we also found a meaningful number of people were diagnosed with other categories of disorders following trauma, including organic disorders like delirium and dementia (2%), personality disorders (1.5%), and neurotic/somatoform disorders like phobias and anxiety disorders (1%).
To help put these percentages in perspective, all categories of psychiatric disorders were more common in people who experienced trauma than in people who experienced the non-traumatic loss of a close family member – ranging from 2 times more common for stress disorders to 5 times more common for personality disorders. Depending on the type of trauma experienced, these ratios could be even higher (see the figure below).
The findings of this study have implications for both clinicians who treat trauma-exposed patients and researchers who study the effects of trauma.
- Importance for clinicians: PTSD and other stress disorders are not the only diagnoses clinicians should consider when assessing people who have experienced trauma. A wide range of additional psychiatric disorders are as common, or almost as common.
- Importance for researchers: National medical registries are an underutilized resource for studying the effects of trauma. The approach developed in this study should be refined and increasingly utilized in order to harness the rich data national medical registries offer.
We conclude that a wide range of mental health disorders should be anticipated following traumatic experiences in addition to, and even in the absence of, PTSD. The impact of trauma can be significant and long-lasting, and medical registry data can help better understand the full range of potential psychopathology related to trauma.
Target Article
Gradus, JL, Rosellini, AJ, Szentkúti, P, Horváth-Puhó, E, Smith, ML, Galatzer-Levy, I, Lash, TL, Galea, S, Schnurr, PP, Sørensen, HT (2022). Using Danish National Registry Data to Understand Psychopathology Following Potentially Traumatic Experiences. Journal of Traumatic Stress. doi: 10.1002/jts.22777
Discussion Questions
- Why have clinicians and researchers traditionally focused more on PTSD than other mental illnesses following trauma?
- Other than PTSD, what might be the most important psychiatric disorders to consider in patients who have experienced trauma?
- What strategies can clinicians use to make sure they are not overlooking less commonly-seen psychiatric disorders in patients who have experienced trauma?
About the Authors
Meghan L. Smith MPH, is a doctoral candidate in Epidemiology at the Boston University School of Public Health. Her research interests include the epidemiology of mental health and the social determinants of health. She is also interested in how research findings are translated to real-world change. She can be contacted at mlsmith1@bu.edu.
Péter Szentkúti, MSc, is a biostatistician at Department of Clinical Epidemiology at Aarhus University in Denmark. His research interest focuses on developing and evaluating machine learning models to support researches related to psychiatric epidemiology. He can be contacted at peter.szentkuti@clin.au.dk.
Jaimie L. Gradus, DMSc, DSc, MPH, is Associate Professor of Epidemiology and Psychiatry at Boston University School of Public Health and School of Medicine. Dr. Gradus's research interests are in the epidemiology of trauma and trauma-related disorders, with a particular focus on suicide. She has been the recipient of multiple National Institute of Mental Health and foundation grant awards to conduct psychiatric epidemiologic research among both veterans and the general population. She can be contacted at jgradus@bu.edu.
References Cited
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