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<div><p>Objective</p><p>This retrospective claims analysis explored the treatment utilization and characteristics among patients with post-traumatic stress disorder (PTSD) of different severity.</p><p>Methods</p><p>The index date was the first PTSD claim. The analysis observed 12 months pre- and 24 months post-index. Adults with insurance gaps, cancer, or acute PTSD during the observation were excluded. Patients were categorized into three severity cohorts based on treatment and healthcare services utilization for PTSD: 1. Baseline PTSD (BP) (no PTSD visits post-index, no FDA-approved medications/ psychotherapy, and no severe mental health comorbidities); 2. PTSD without Comorbidities (PwoC) (≥1 PTSD visits post-index and no severe mental health conditions); 3. PTSD with Comorbidities (PwC) (≥1 PTSD visits post-index and severe mental health comorbidities present). For the primary analysis, cohorts were propensity-score matched. A sub-analysis examined patients with PTSD and Substance or Alcohol Use Disorder (SUD/AUD).</p><p>Results</p><p>The primary analysis observed 1714 BP, 1681 PwoC, and 1681 PwC patients. Treatment utilization rates were highest among PwC vs. other cohorts (84.5% psychotherapy, 76.1% off-label medications, and 26.1% FDA-approved medications [p<0.001]). PwC cohort also had the highest number of psychotherapy sessions and medication prescriptions per patient (20.1 sessions, 12.6 off-label prescriptions, and 2.0 FDA-approved prescriptions [p<0.001]). The proportion of days covered (PDC) indicated low medication adherence (0.25–0.40) with adherent patient rates (PDC ≥0.80) between 8.0–17.5%. The SUD/AUD sub-analysis identified 85 BP, 537 PwoC, and 3154 PwC patients. Conclusions were similar, with PwC cohort having highest treatment utilization rates (87.1% psychotherapy, 85.0% off-label medications, 28.2% FDA-approved medications [p≤0.013] with 24.4 sessions, 16.1 off-label prescriptions, and 2.0 FDA-approved prescriptions per patient [p≤0.002]). Only 4.7–11.4% of patients were adherent.</p><p>Conclusions</p><p>PwC patients received psychotherapy and pharmacotherapy more frequently than PwoC and BP patients. Medication adherence among treated patients was low. Patients with SUD/AUD had numerically higher treatment utilization and lower medication adherence.</p></div>