PATTERNS OF CHANGE IN RESPONSE TO PROLONGED EXPOSURE: IMPLICATIONS FOR TREATMENT OUTCOME

Assessment of response to Prolonged Exposure (PE) suggests some patients may experience discontinuous change involving sudden symptom reductions and/or temporary exacerbations. The current study looked to (1) isolate profiles of PE response among treatment-seeking veterans and (2) identify factors associated with unique patterns of change.

Archival records were examined for veterans receiving PE through a specialty Veterans Affairs Medical Center (VAMC) clinic (N = 109). Latent profile analysis was used to extract response trajectories defined by change in weekly PTSD Checklist (PCL) scores. Associations with provider status (staff vs. intern), setting (in-person vs. telehealth), initial severity (PTSD; depression), and eventual treatment gains were examined.

Three profiles were observed. Rapid Responders (18.3%) evidenced sharp reductions at Week 2 and again between Weeks 5 and 6. Linear Responders (40.4%) demonstrated gradual reductions throughout the 10-week assessment window. Delayed Responder (41.3%) scores were relatively stable over the evaluation period although final session outcomes indicated reliable change (PCLΔ > 10) in 40% of patients. Profiles were similar with respect to provider status, treatment setting, and initial symptom severity. Rapid Responders evidenced lower final session scores relative to Linear (g = 1.13) and Delayed (g = 1.85) groups, with Linear Responders reporting lower end scores than Delayed Responders (g = 1.02).

Anticipating patterns of recovery and their association with therapeutic outcome is of immense clinical value. Sudden gains emerged as a strong predictor of enhanced response. Data also suggest potential benefits of extending standard intervention for patients who fail to demonstrate an immediate response to PE.