StrongVeterans.com BlogHow Do Symptoms of PTSD Cluster in DSM-5?

Most people have experienced some type of trauma in their lives and have subsequently felt aftereffects, which we have come to term posttraumatic stress. If the posttraumatic stress is persistent and impairs functioning, it can become a disorder. But many different types of posttraumatic stress symptoms exist, and we continue to refine which symptoms constitute posttraumatic stress disorder (PTSD). The latest refinement occurred in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5). The DSM-5 introduced several new PTSD symptoms and tinkered with a few previously described symptoms to better define how to diagnose the disorder. However, how these new and refined symptoms cluster with other symptoms was unclear. Knowing how different symptoms of PTSD cluster together would help us conceptualize the major symptom components of the disorder. When symptoms often overlap with others, they presumably together represent a broader symptom component. To make a medical analogy, when symptoms of a sore throat, cough, and excess phlegm are found together, they represent disruptions in the respiratory system that can mean the patient has a cold.

Veterans are an important and ideal population in which to study posttraumatic stress not only because of their higher potential exposure to trauma than the general public but also because we care about the well-being of those who have served. My colleagues and I conducted a study using a nationally representative sample of 1,484 US veterans to understand the prevalence of DSM-5 PTSD, the major symptom components of the disorder, and how different symptom components are related to important outcomes. Using a web-based survey, we assessed various mental health symptoms, including those of PTSD, and other aspects of their lives, such as quality of life.

We found that 12% of US veterans screened positive for lifetime PTSD and 5.2% screened positive for past-month PTSD. In analyzing how DSM-5 PTSD symptoms cluster, we found 6 major symptom components that we called re-experiencing symptoms, avoidance symptoms, emotional numbing symptoms, externalizing behaviors, dysphoric arousal symptoms, and anxious arousal symptoms. Furthermore, we found that these major symptom components were related to different outcomes. For example, emotional numbing symptoms were more strongly related to depression, suicidal thoughts, and decreased quality of life than other symptom components, and externalizing behaviors were more strongly related to hostility than other symptom components.

These findings may help further efforts to understand, diagnose, and treat PTSD. Different symptom components may exist differently in our neurobiology, making some better targets for certain treatments than others. Because PTSD is a complex disorder, we should expect to continually refine how we understand and conceptualize it.

Financial disclosure:Dr Tsai had no relevant personal financial relationships to report.