Similarities and Differences Between PTSD, Depression, and Other Major Mood Disorders

(Part 1 of 2)

In this video, Lisa Brenner PhD, director of the Rocky Mountain Mental Illness Research Education and Clinical Center, Denver, Colorodo, discusses how the similarities between post-traumatic stress disorder (PTSD) and other major mood disorders, such as depression, can lead to misdiagnosis.

Dr Brenner also explains the key differences between PTSD and other disorders that clinicians should look out for when making a diagnosis. Recently, Dr Brenner and co-authors published a study that evaluated the developments in screening tools for PTSD using computerized adaptive testing. 

Watch Co-Author, Robert Gibbons, PhD, discuss the study.

Read the transcript:

Hi, my name is Lisa Brenner. I'm a clinical research psychologist and the director of the Rocky Mountain Mental Illness Research Education and Clinical Center at the VA, here in Denver, Colorado.

We're in Denver, but we're an asset to the country. We are focused on suicide and suicide prevention for veterans, but really for all Americans. I'm also a professor at the University of Colorado, Anschutz Medical Campus, in the departments of Physical Medicine and Rehabilitation, Psychiatry, and Neurology.

How often PTSD is misdiagnosed or mistaken for another major mood or mental health disorder

I'm here today to talk about PTSD, and I know that people can also have the opportunity to listen to my colleague talk about the development of a measure that we created together, Robert Gibbons. He has been recorded previously on this topic.

Today, I'm hoping to focus a little bit on the clinical pieces associated wide with why we decided to work on this tool together and some of the missteps that we traditionally can make in mental health, and how having this tool can help us do a little bit better job in terms of diagnosing PTSD.

Often PTSD is missed as a diagnosis. I wouldn't say this is the case in VA or other military settings where we're pretty used to talking about PTSD, but I think other clinicians sometimes see PTSD much less frequently than they see anxiety or other depressive disorders, and they may forget to ask about it, or just you'd have to practice about asking about it.

One way to combat this is to include in your intake process a specific question about traumatic stressors. This should be a very broad question. It can focus on exposure to potential death, or threatened death, actual or threatened sexual violence, or other serious injury or violence.

Including a question like that in your intake questionnaire or your intake interview, allows you to begin to learn whether people have direct exposure to trauma, have witnessed traumatic events, have been close to people who have been exposed to a trauma. This will let you know if you have the number one criteria for PTSD, a traumatic exposure.

If you do have that traumatic exposure, you want to go on a bit further and look to see if they have several different symptoms.

More recently, in the DSM‑5, there's a new criteria for PTSD. As you're going to hear in a moment, this new criterion has a number of different symptoms associated with it, and you have to have a smattering of each.

Now, one thing I want you to keep in mind is because there are these different symptom categories, and within the different symptom categories, you can have symptoms very differently, that PTSD from one person to the next can look very different and that can make it very hard to diagnose or confusing.

The categories that you need to have symptoms in are re-experiencing symptoms, avoidance symptoms, at least two arousal and reactivity symptoms, and at least two cognition and mood symptoms. That latest cognition and mood symptoms was recently added and has created some confusion about comorbidities, but I'll talk about that a bit more.

Specifically, I do want to visit the symptoms specifically for each of the criteria. Re-experiencing symptoms include things like flashbacks, bad dreams, or frightening thoughts.

We're used to thinking about flashbacks and nightmares, but we less often ask people about, are you having re‑experiencing or feeling like you're very triggered by your own thoughts and feelings when you're reminded of an event?

I found in my practice that the re‑experiencing, having frightening thoughts or feelings when reminded of something is more frequent than flashbacks. I'd say second frequently than is bad dreams.

Avoidance symptoms include staying away from people, places, or events that remind you of the traumatic experience or avoiding thoughts and feelings related to the traumatic event. What people find is that their world becomes smaller and smaller while they're trying to avoid things.

Let's say their traumatic stressor is associated with a motor vehicle accident. Initially, maybe they'll have trouble being a driver on a car, and then it may spread, and they may have trouble being a passenger in a car.

Maybe they're OK if they're on a local road, but it's not as good if they're on highways. Then it may spread to even not wanting to be in a car at all. If you see this kind of avoidance and then this creeping avoidance that gets more and more encompassing, that's fairly typical of PTSD.

The next symptom category is arousal and reactivity. This includes being easily startled, tense, having difficulty sleeping, having angry outbursts, irritability. These arousal symptoms are usually pretty constant. They can be made worse by triggers, but generally, people have these most of the time or quite a bit of the time.

Finally, these cognition and mood symptoms are symptoms that do overlap with a lot of our other conditions, but they are also pertaining to PTSD. This can be negative thoughts about yourself or the world, distorted feelings around blame, or guilt, or shame, loss of interest in enjoyable activities.

These symptoms can come up right after the event, but they can persist. One really important thing, I'll talk about this as I talk about comorbidities, is that these are not related to another condition or disorder. They're not related to substance abuse. They're not related to its own freestanding depression, but they are related to the trauma itself.

These symptoms also have a way of help making people feel very alienated from the world around them, from family members, from friends. They can also foster things like isolation and detachment because people feel further and further away from those around them, which then cycles around. Their negative thoughts and feelings about themselves and the world can be reinforced.

Many of these symptoms, you've heard me talk about avoidance growing, or these negative mood and cognitive symptoms growing, many of these things seem to take on a life of their own and can reinforce themselves and each other, which can create more severity in terms of PTSD diagnosis.

The similarities between PTSD and other mood disorders that may lead to this misdiagnosis

As I noted above, because of the different symptoms and the way that different symptoms can fit together and still meet the criteria for PTSD, people can have symptom presentations that look quite different.

Some people can meet criteria but have more depressive symptoms. Some people can meet criteria but have more the reactivity on the cognitive distortion of the world around them. There's a number of conditions that can look similar to PTSD.

To make it more difficult, the number of these conditions also are frequently comorbid with PTSD. That would mean that you actually have you meet criteria for PTSD, but you also independently meet criteria for another disorder.

Depending on how your symptoms look, or how a patient's symptoms look, people often can confuse depression, anxiety disorders. I have people sometimes confuse maybe phobia, people talk about a social anxiety disorder, where people are nervous around being around other people.

It's actually that they're nervous, let's say you were in Iraq and Afghanistan and you learned, while you were there, that being in crowded place is very dangerous at times. There could be hidden bombs or hidden explosives there. That you learned that crowded places are dangerous, and that could look like social anxiety or phobia.

Sometimes we've also noticed with irritability and extreme irritability, people can get confused to think that people have bipolar II disorder when actually it's irritability associated with a traumatic event.

That being said, you can have co‑occurrences and they frequently coexist. One thing that I often look about is timeline. Let's say somebody had a previous history of major depressive disorder and then has a traumatic exposure, and then develops PTSD. Timelines and developmental cause of psychiatric concerns is something that I frequently ask about and try to keep track of that over time.

The other thing that I think is important to note is a number of individuals with some of these symptoms ‑‑ and some of these symptoms can be very, very uncomfortable, the agitation, the irritability, the reactivity ‑‑ and so people do try to self medicate with alcohol and other substances.

Frequently, individuals also have co‑occurring, not everybody, but frequently, individuals have co‑occurring substance use disorders also. Really important in this mix is to try to figure out how people are dealing with these symptoms that can be so uncomfortable and then asking explicitly about use of substances and misuse of substances to try to treat symptoms.

Are there any other key differences in symptoms that clinicians should look out for?

One thing I want to highlight here is the starting point. We talked about that a bit before. The starting point should be about asking for this traumatic event. You cannot have PTSD without the traumatic event.

If people have all these clustering of symptoms but no traumatic event, that wouldn't be PTSD. Starting from the beginning, the number one criteria A for PTSD should help clinicians be able to ferret out whether or not this is PTSD or something else.

Even when using a tool like the CAT or the CAD, the CAD for adaptive diagnosis, or the CAT to see about symptom severity, both of which are important, you're always going to want to circle back to make sure that these symptoms are associated with a traumatic event. Because if they're not, then this is not PTSD.


Brenner LA, Betthauser LM, Penzenik M, et al. Development and Validation of Computerized Adaptive Assessment Tools for the Measurement of Posttraumatic Stress Disorder Among US Military Veterans. JAMA Netw Open. 2021;4(7):e2115707. Published 2021 Jul 1. doi:10.1001/jamanetworkopen.2021.15707

Lisa A Brenner, PhD, is a Board-Certified Rehabilitation Psychologist, a Professor of Physical Medicine and Rehabilitation (PM&R), Psychiatry, and Neurology at the University of Colorado, Anschutz Medical Campus, and the Director of the Department of Veterans Affairs Rocky Mountain Mental Illness Research, Education, and Clinical Center (MIRECC). She is also Vice Chair of Research for the Department of PM&R. Dr Brenner is the Past President of Division 22 (Rehabilitation Psychology) of the American Psychological Association (APA) and an APA Fellow. She serves as an Associate Editor of the Journal of Head Trauma Rehabilitation. Her primary area of research interest is traumatic brain injury, co-morbid psychiatric disorders, and negative psychiatric outcomes including suicide. Dr. Brenner has numerous peer-reviewed publications, participates on national advisory boards, and has recently co-authored a book titled: Suicide Prevention After Neurodisability: An Evidence-Informed Approach.