Obsessive-compulsive disorder (OCD) is usually treated as a stand-alone mental illness. A growing body of research is now finding that some cases of OCD may stem from trauma. For these patients, successful treatment may hinge on targeting the coexisting post-traumatic stress disorder (PTSD).
Over the past decade researchers have discovered that for some people, obsessive behaviors such as repetitive washing or hoarding may be a way of coping with post-traumatic stress. In a 2003 study of patients with both disorders, psychiatrist Beth R. Gershuny of Bard College found that as OCD symptoms decreased with treatment, PTSD symptoms—such as flashbacks and nightmares—became worse. She more recently showed that 82 percent of treatment-resistant OCD patients reported a history of trauma, with 39 percent of those meeting the criteria for PTSD. A picture of the interplay began to emerge: if a patient's past trauma is not addressed, targeting his or her OCD will not restore mental health.
Most recently, a study of 1,000 adults with OCD supported the idea of a post-traumatic subtype of OCD. Published in the March Journal of Anxiety Disorders, the study compared the symptoms of three groups: those who developed OCD after PTSD (referred to in the study as post-traumatic OCD), those who developed OCD before PTSD, and those who did not have a history of trauma. People with post-traumatic OCD tended to have a more severe collection of symptoms than those in the other groups, including more thoughts of suicide, higher levels of anxiety and depression, and greater hoarding and compulsive spending.
Leonardo F. Fontenelle of the Institute of Psychiatry at the Federal University of Rio de Janeiro, and lead author of the March article, says it is difficult to say for sure whether some cases of OCD are actually caused by trauma, “but there are an increasing number of OCD cases being reported after traumatic events.”
Currently clinicians do not routinely ask whether an OCD patient has experienced trauma, a potential obstacle to recovery. Both OCD and PTSD are anxiety disorders and are treated with similar drugs, but cognitive therapies for the two disorders differ. Cognitive-behavior therapy, a popular and effective type of talk therapy, treats OCD with mental exercises designed to curb its characteristic urges and ruminations. For the post-traumatic subtype of OCD, treatment “may be improved by the addition of anti-PTSD strategies,” says Fontenelle, such as recalling the traumatic events systematically in a safe setting until the emotional power of the memories is diminished.