Should patient adherence to medical home be enforced? Impact of adherence on emergency and inpatient utilization

Background: An essential principal of the patient-centered medical home (PCMH) is for each patient to have an ongoing relationship with a personal physician who provides continuous and comprehensive care. The promise of PCMH in improving efficiencies and overall patient health cannot be fully realized, arguably, if patients frequently visit multiple primary care providers (PCP). This study examines whether enforcement of adherence to the same PCMH has an impact on utilization of potentially avoidable emergency room and inpatient visits. Methods: Two years of enrollment and claims data from a California county that participated in the safetynet-based Health Care Coverage Initiative (HCCI) demonstration project were used; the first year prior to enforcement of PCMH adherence and the second with enforcement of adherence. Adherence was enforced by denying payment for non-urgent visits to non-PCMH PCPs. Dependent variables included any emergency room visit followed by discharge or inpatient admission, number of each type of ER visit, any inpatient visits, and number of inpatient visits and average length of stay for those hospitalized. Logistic, Poisson, and negative binomial regressions were used to assess emergency room and inpatient visits in the pre and post adherence enforcement periods and controlled for length of enrollment in the program, six chronic diseases, comorbidities, and demographics. HCCI enrolled adults age 21-64, who had incomes up to 200% of the Federal Poverty Level and were legal U.S. citizens and residents were included. Those with a minimum of 6 months of enrollment in each study year were included (N=10,984). Results: The percentage of outpatient primary care visits at the medical home increased from 38% in the pre to 74% in the post period. The likelihood of any ER visit followed by inpatient admission (OR=0.85) and likelihood of any inpatient visits (OR=0.79) declined significantly in the post period, but other measures did not differ in the pre and post periods. Conclusions: Adherence to PCMH can reduce utilization of potentially avoidable inpatient visits and is likely to reduce costs. This effect may be due to the improved ability of the PCPs to maintain patient health by better coordination of care and follow up of patients within the primary care setting. Enforcing adherence can be considered as a reliable mechanism in implementation of PCMH, particularly among low-income populations who receive their care within the safetynet.