Changes in Service Use After Participation in an Intensive Outpatient Program Among Adults With Posttraumatic Stress Disorder.

ABSTRACT

INTRODUCTION: Intensive outpatient programs (IOPs) have been shown to reduce posttraumatic stress disorder (PTSD) symptoms in veteran populations. The aim of this study was to examine the association between IOP participation and inpatient psychiatric and mental health-related emergency department (ED) encounters among patients with PTSD. METHODS: This is a retrospective cohort study among 258 adults with PTSD who participated in the IOP at Kaiser Permanente Oakland Medical Center between January 1, 2017, and December 31, 2018. The authors compared changes in inpatient psychiatric hospitalizations and mental health-related ED encounters from the year before vs after the first IOP engagement. Bivariate analyses comparing ED and inpatient utilization pre- and post-IOP engagement, stratified by sociodemographic variables were conducted using paired t-tests and McNemar's test. Conditional multivariable logistic regression was performed to assess the odds of psychiatric utilization. RESULTS: Participants were more likely to have ≥ 1 inpatient psychiatric encounter (28.7% vs 15.9%; p < 0.01) and ≥ 1 mental health-related ED encounter (24.8% vs 18.2%; p = 0.04) pre-IOP vs post-IOP. The authors' multivariable analysis demonstrated that patients experienced a 56% reduction in the odds of inpatient psychiatric encounters (adjusted odds ratio = 0.42, 95% confidence interval 0.26-0.68, p < 0.01) and a 35% reduction in mental health-related ED encounters (adjusted odds ratio = 0.63, 95% confidence interval 0.40-1.00, p = 0.05) post-IOP vs pre-IOP. DISCUSSION: This study demonstrated a significant reduction in inpatient psychiatric hospitalizations and mental health-related ED visits among patients with PTSD in the year following participation in an IOP. CONCLUSION: These findings support the use of IOPs for patients with PTSD to reduce the likelihood of intensive service use.