Delayed-onset post-traumatic stress disorder among war veterans in primary care clinics.

BACKGROUND Only limited empirical data support the existence of delayed-onset post-traumatic stress disorder (PTSD). AIMS To expand our understanding of delayed-onset PTSD prevalence and phenomenology. METHOD A cross-sectional, epidemiological design (n = 747) incorporating structured interviews to obtain relevant information for analyses in a multisite study of military veterans. RESULTS A small percentage of veterans with identified current PTSD (8.3%, 7/84), current subthreshold PTSD (6.9%, 2/29), and lifetime PTSD only (5.4%, 2/37) met criteria for delayed onset with PTSD symptoms initiating more than 6 months after the index trauma. Altogether only 0.4% (3/747) of the entire sample had current PTSD with delayed-onset symptoms developing more than 1 year after trauma exposure, and no PTSD symptom onset was reported more than 6 years post-trauma. CONCLUSIONS Retrospective reports of veterans reveal that delayed-onset PTSD (current, subthreshold or lifetime) is extremely rare 1 year post-trauma, and there was no evidence of PTSD symptom onset 6 or more years after trauma exposure.