Does "subthreshold" posttraumatic stress disorder have any clinical relevance?

The present report examined the extent to which subthreshold posttraumatic stress disorder (PTSD) (without lifetime PTSD) and full PTSD are associated with impairment or distress, controlling for comorbidity (i.e., major depression and panic disorder) in a sample of treatment-seeking psychiatric patients. Patients were administered diagnostic interviews and assessed for psychosocial impairment and whether or not they desired treatment for their PTSD symptoms. No significant differences were found between patients with full PTSD (N = 156) and those with subthreshold PTSD (N = 56) in degree of impairment (i.e., social and work functioning, as well as number of suicide attempts). In contrast, those with full PTSD had significantly more psychiatric hospitalizations and worse global functioning and were more likely to want treatment for their PTSD symptoms compared to those with subthreshold PTSD, albeit the majority of patients with subthreshold PTSD wanted treatment for their PTSD symptoms. These findings, like past research, suggest that subthreshold PTSD is associated with levels of social and work morbidity comparable to full PTSD. However, the report also underscores the difficulties in identifying a set of clinical criteria that clearly delineates between full PTSD and subthreshold PTSD.