Predictors of Symptom Increase in Subsyndromal PTSD Among Previously Deployed Military Personnel

Subsyndromal PTSD (sub-PTSD) is associated with functional impairment and increased risk for full PTSD. This study examined factors associated with progression from sub-PTSD to full PTSD symptomatology among previously deployed military veterans.

Data were drawn from a longitudinal survey of Navy and Marine Corps personnel leaving military service between 2007 and 2010 administered immediately before separation (baseline) and ~1 year later (follow-up). Survey measures assessed PTSD symptoms at both times; the baseline survey also assessed potential predictors of symptom change over time. Logistic regression models were used to identify predictors of progression from sub-PTSD to full PTSD status.

Compared to those with no or few PTSD symptoms at baseline, individuals with sub-PTSD were almost three times more likely to exhibit full PTSD symptomatology at follow-up. Risk factors for symptom increase among those with sub-PTSD included moderate or high levels of combat exposure and utilization of fewer positive coping behaviors. Use of prescribed psychotropic medication was protective against symptom increase.

This study identified several predictors of symptom increase in military veterans with sub-PTSD. Interventions targeting modifiable risk factors for symptom escalation, including behavioral and pharmacological treatments, may reduce rates of new-onset PTSD in this population.