The Impact of Rhode Island's Multipayer Patient-centered Medical Home Program on Utilization and Cost of Care.

ABSTRACT

OBJECTIVE: To estimate the effect of patient-centered medical home (PCMH) participation on cost and utilization of care for patients in Rhode Island's statewide, multipayer PCMH program, which serves over one-third of the state population. DATA SOURCES/STUDY SETTING: 2009-2014 claims data from all payers in Rhode Island, representing >743,000 unique patients. STUDY DESIGN: A propensity score-matched difference-in-differences framework was used to separately estimate the effect of the PCMH on 3 patient cohorts, which were defined by their intervention start dates and amounts of implementation time. Outcomes included patient costs (total, inpatient, outpatient, professional, pharmacy) and utilization [emergency department (ED) visits, preventable ED visits, inpatient admissions, preventable inpatient admissions, all-cause 30-day readmissions]. Interaction effects were estimated to assess heterogeneity among clinical risk groups and payers. PRINCIPAL FINDINGS: There was no evidence of a PCMH effect on total costs, though we observed evidence of an increase in the odds of PCMH patients having outpatient and professional costs, and in one cohort, a decrease in inpatient costs for those with an inpatient visit. We also observed evidence of reduced ED visits, preventable ED visits, and inpatient admissions for PCMH patients. While subgroup effects varied by cohort and measure, high-risk patients often experienced the largest reductions in ED visits. CONCLUSIONS: All PCMH cohorts experienced statistically significant reductions in some types of utilization in as little as 1.25 years. Reductions were greatest for measures included in the PCMH contractual agreement. While PCMH programs may not expect cost savings in the short-term, costs could potentially be reduced in the longer-term through avoided ED and inpatient expenses.