Assessing the Effect of the VHA PCMH Model on Utilization Patterns Among Veterans With PTSD

OBJECTIVES: The Veterans Health Administration (VHA) implemented a patient-centered medical home (PCMH)-based Patient Aligned Care Teams (PACT) model in 2010. We examined its effects on the utilization of health services among US veterans with posttraumatic stress disorder (PTSD). STUDY DESIGN: We analyzed VHA clinical and administrative data to conduct an interrupted time series study. Encounter-level data were obtained for the period of April 1, 2005, through March 31, 2014. We identified 642,660 veterans with PTSD who were assigned to either a high- or low-PCMH implementation group using a validated VHA PCMH measurement instrument. METHODS: We measured the effect of high-PCMH implementation on the count of hospitalizations and primary care, specialty care, specialty mental health, emergency department (ED), and urgent care encounters compared with low-PCMH implementation. We fit a multilevel, mixed-effects, negative binomial regression model and estimated average marginal effects and incidence rate ratios. RESULTS: Compared with patients in low-PCMH implementation clinics, patients who received care in high-PCMH implementation clinics experienced a decrease in hospitalizations (incremental effect [IE], -0.036; 95% confidence interval [CI], -0.0371 to -0.0342), a decrease in specialty mental health encounters (IE, -0.009; 95% CI, -0.009 to -0.008), a decrease in urgent care encounters (IE, -0.210; 95% CI, -0.212 to -0.207), and a decrease in ED encounters (IE, -0.056; 95% CI, -0.057 to -0.054). CONCLUSIONS: High PCMH implementation positively affected utilization patterns by reducing downstream use of high-cost inpatient and specialty services. Future research should investigate whether a reduction in utilization of health services indeed results in higher levels of virtual and non-face-to-face access, or if the PACT model has reduced necessary access to care.