Differences in Intolerance of Uncertainty in OCD and Comorbid PTSD Underlying Attenuated Treatment Response
Abstract
Extant research has found that patients with OCD+PTSD experience significantly worse symptoms, have higher treatment dropout rates, and are less
responsive to treatment. While both disorders are characterized by intolerance of uncertainty (IU), it has been suggested that IU presents differently in OCD
and PTSD. Specifically, individuals with OCD report greater struggles with prospective IU, or perceptions of threat related to future uncertainty, and individuals
with PTSD report greater struggles with inhibitory IU, or inability to function in the face of uncertainty. However, it is not known how IU presents in patients with
OCD+PTSD. Differences in IU were examined in patients with OCD+PTSD compared to OCD using a sample of 475 residential inpatients in an OCD and
anxiety treatment program, and change in IU was examined as a potential mediator to symptom change across treatment. Patients with OCD+PTSD reported
significantly greater inhibitory and prospective IU compared to patients with OCD and did not experience significant improvement in IU from baseline to
discharge. In addition, they experienced significantly less OCD symptom improvement compared to patients with OCD. Whereas improvement in prospective
IU partially explained OCD symptom improvement in patients with OCD, the same was not true for patients with OCD+PTSD. Findings suggest that IU should
be of greater treatment focus when working with patients with OCD+PTSD; specific clinical recommendations are provided.