Building care systems to improve access for high-risk and vulnerable veteran populations.

For many high-risk patients, accessing primary care is challenged by competing needs and priorities, socioeconomics, and other circumstances. The resulting lack of treatment engagement makes these vulnerable patient populations susceptible to poor health outcomes and an over-reliance on emergency department-based care. We describe a quasi-experimental pre-post study examining a vulnerable population-based application of the patient-centered medical home applied to four high-risk groups: homeless veterans, cognitively impaired elderly, women veterans and patients with serious mental illness. We measured 6-month primary care, emergency department and inpatient care use and chronic disease management when care was based in a general internal medicine clinic (2006) and in a population-specific medical home (2008). Overall 457 patients were studied, assessing care use and outcomes for the last 6 months in each study year. Compared with 2006, in 2008 there was a significant increase in primary care use (p <0.001) and improvement in chronic disease monitoring and diabetes control (2006 HBA1C: 8.5 vs. 2008 HBA1C 6.9) in all four groups. However, there was also an increase in both emergency department use and hospitalizations, albeit with shorter lengths of stay in 2008 compared with 2006. Most of the increased utilization was driven by a small proportion of patients in each group. Tailoring the medical home model to the specific needs and challenges facing high-risk populations can increase primary care utilization and improve chronic disease monitoring and diabetes management. More work is needed in directing this care model to reducing emergency department and inpatient use.