By Nancy Skopp, Ph.D
Nov. 16, 2020

U.S. Air Force photo by Senior Airman Christian Clausen

Obsessive compulsive disorder (OCD) and posttraumatic stress disorder (PTSD) rank among the most debilitating, distressing, difficult and expensive-to-treat mental health conditions. While the two conditions were once considered to be unrelated, accumulating evidence indicates they often co-occur.

• Estimated rates of PTSD and OCD co-occurrence range from 24 to 41 percent.
• PTSD patients with symptoms of OCD appear to exhibit more severe PTSD than those without OCD.
• Co-morbid OCD and PTSD is particularly challenging to treat.

OCD and PTSD commonly occur in people with trauma history. Although the association between the co-occurrence of the two disorders is unclear, some researchers have speculated that obsessive-compulsive behavior may be used to cope with, reduce, and avoid trauma-related stimuli.

Assessment

Screening and treatment for PTSD are routine in DOD and VA health care systems, however, OCD often goes unrecognized and untreated, or is inadequately treated. A recent study showed that less than half of VA providers could identify exposure and response prevention (ERP) as the frontline treatment for OCD, and less than 25 percent had training in OCD treatment.

OCD and PTSD share some symptoms:

• Feelings of disgust or guilt
• Recurrent, intrusive memories or thoughts that induce distress
• Behaviors and actions that reduce or neutralize distress (e.g., rituals, isolation, avoidance)

Disentangling the symptoms of OCD and PTSD can be tricky. A clinician may recognize and treat PTSD symptoms but may not identify and address co-occurring OCD. It can further complicate OCD diagnosis that some patients do not exhibit behavioral compulsions such as checking but instead engage in less observable mental rituals. Use of OCD screening and assessment tools among PTSD patients, coupled with availability of training for evidence-based OCD treatment, is essential.

Treatment

When addressing PTSD it is important for providers to be aware of a potential co-occurrence of OCD and how it may influence treatment. If only one disorder is identified and treated, the failure to consider the other may greatly intensify patient distress. And when both disorders are co-occurring, treatments targeted separately for each can sometimes be counterproductive. ERP treatment is the psychotherapeutic treatment of choice for OCD, while cognitive behavioral therapies (CBTs) such as prolonged exposure and cognitive processing therapy are recommended by VA/DOD clinical practice guidelines for PTSD. However, ERP treatment for OCD has been shown in some cases to be adversely influenced by co-occurring PTSD. Clinicians should assess for both PTSD and OCD in trauma patients to better direct the appropriate combinations of treatments and ensure the overall quality of care. Neglecting to do so can significantly reduce treatment efficacy and contribute to patient distress.

Additional resources

The International OCD Foundation is a donor-supported nonprofit organization that provides resources and training for clinicians as well as links to resources for OCD sufferers and their families, including support groups and teletherapy.

Although there is no VA/DOD clinical practice guideline for the treatment of OCD or co-occurring OCD and PTSD, you can consult the VA/DOD guideline for PTSD and other relevant links for PTSD treatment.

The VA's South Central Mental Illness Research Education and Clinical Center provides a fact sheet on Examining the Differential Diagnosis Between OCD and PTSD.

Dr. Skopp is a research psychologist at the Psychological Health Center of Excellence West at Joint Base Lewis McChord in Tacoma, WA and an affiliate associate professor at the University of Washington Department of Psychiatry and Behavioral Sciences. Her expertise is in military psychological health research.