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J Ambulatory Care Manage Vol. 37, No. 4, pp. 331–338 C 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins Copyright 

Elements of the Patient-Centered Medical Home Associated With Health Outcomes Among Veterans The Role of Primary Care Continuity, Expanded Access, and Care Coordination Karin Nelson, MD, MSHS; Haili Sun, PhD; Emily Dolan, PhD; Charles Maynard, PhD; Laruen Beste, MD; Christopher Bryson, MD, MS; Gordon Schectman, MD; Stephan D. Fihn, MD, MPH Abstract: Care continuity, access, and coordination are important features of the patient-centered medical home model and have been emphasized in the Veterans Health Administration patientcentered medical home implementation, called the Patient Aligned Care Team. Data from more than 4.3 million Veterans were used to assess the relationship between these attributes of Patient Aligned Care Team and Veterans Health Administration hospitalization and mortality. Controlling for demographics and comorbidity, we found that continuity with a primary care provider was associated with a lower likelihood of hospitalization and mortality among a large population of Veterans receiving VA primary care. Key words: continuity, medical home, primary care

Author Affiliations: VA Puget Sound Healthcare System, Northwest HSR&D Center of Excellence (Drs Nelson, Sun, Dolan, Maynard, Beste, and Bryson), VA Puget Sound Healthcare System, General Internal Medicine Service (Drs Nelson, Beste, Bryson, and Fihn), Department of Medicine, School of Medicine, University of Washington (Drs Nelson, Beste, Bryson and Fihn), Department of Health Services, School of Public Health, University of Washington (Dr Maynard), and VHA Office of Analytics and Business Intelligence (Dr Fihn), Seattle, Washington; and VHA Patient Care Services, Primary Care Program Office, Milwaukee, Wisconsin (Dr Schectman). This paper was presented at the National Society for General Internal Medicine meeting in Denver, Colorado, on April 25, 2013. This study was supported by the Veterans Health Administration Patient Care Services. Data for this report were developed by the national evaluation team at the PACT Demonstration Lab Coordinating Center and the VHA Office of Analytics and Business Intelligence. The VHA Office of Primary

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HE patient-centered medical home (PCMH) is a promising model to implement key components essential for primary care services that include increasing access to services, creating a longitudinal relationship with a primary care team to increase continuity of care, and improving care coordination and comprehensiveness of care (Kringos et al., 2010). The Veteran’s Health Administration (VHA) is the largest integrated US health system and is currently implementing

Care Operations is responsible for PACT implementation and the VHA Office of Patient Care Services is responsible for the PACT Demonstration Lab program. We have no conflicts of interest to report. Correspondence: Karin Nelson, MD, MSHS, VA Puget Sound Health Care System HSR&D, 1100 Olive Way, Ste 1400, Seattle, WA 98108 ([email protected]). DOI: 10.1097/JAC.0000000000000032

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a PCMH model. This restructuring, called the Patient Aligned Care Team (PACT), seeks to improve primary care services through expanded access, continuity, and coordination of health care services for the Veteran population (Rosland et al., 2013). Although described as essential elements of primary care, the relative contributions to health outcomes for each of these components are not certain. It is not clear whether expanded primary care access or continuity within PCMHs improve patients’ risk of hospitalization or mortality. Thus, we sought to ascertain the association between basic components of the PCMH (expanded access, continuity, and care coordination) with hospitalization and mortality among patients receiving primary care from VHA. METHODS This study is part of the VHA National PACT evaluation, a VHA initiative for evaluating the implementation of the VHA’s PCMH model. Patient population Among all Veterans enrolled in primary care 1 year prior to the formal initiation of efforts to establish the PACT at all sites delivering primary care (ie, the time period between April 2009 and April 2010), we analyzed individuals who had made 2 or more primary care visits. A total of N = 4 328 714 Veterans were assigned to primary care at the start of our study period (April 2009). We restricted our sample to Veterans with more than 2 primary care visits (n = 2 630 171) because continuity measures are less reliable for patients with fewer visits. Data sources Using the Primary Care Management Module contained within VHA’s Corporate Data Warehouse, we identified all patients who were enrolled and assigned to a primary care provider (PCP) within the Veterans Health Administration (VHA) from April 2009 to April 2010. Information about demographic, clinical characteristics, and health services utilization was obtained from the Corporate Data Warehouse.

Dependent variables We defined outcomes as a hospitalization or death from any cause during the year April 2010 to April 2011. Hospitalizations were identified from the VHA inpatient file. We included any patient who had a discharge record in that file during April 2010 to April 2011. Deaths were identified using the VHA vital status file (Sohn et al., 2006). Covariates Clinical data included ICD-9 (International Classification of Diseases, Ninth Revision) codes recorded during the year April 2009 to April 2010 at all clinical encounters. The Deyo adaptation of Charlson score was used to measure comorbidity (Charlson et al., 1987; Deyo et al., 1992). Demographic information included age, gender, race/ethnicity, and service connection status. The VHA eligibility was defined by enrollment in priority groups on the basis of service-connected conditions, length of military service, disability, and income. The highest priority group included Veterans with a service-connected disability 50% or more. Primary care domains Continuity The PACT model emphasizes continuity of care with an assigned provider. To assess continuity, we used Usual Provider Continuity (Breslau & Reeb, 1975), a continuous measure representing the percentage of all primary care office visits with physicians, nurse practitioners, and physician’s assistants that were made to the patient’s assigned PCP (number of PCP visits/number of overall primary care clinic visits). For each Veteran, we assigned the Usual Provider Continuity measure into 1 of 3 categories (Rodriguez et al., 2007): (1) high (1.0), (2) moderate (0.50-0.99), or (3) low (< .50). Visits to urgent care, emergency department, and non-VHA providers were excluded. We also examined indicators of teambased care, such as visits with the clinic nurse or pharmacist.

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Primary Care Continuity and Health Outcomes Expanded access Expanded access to care outside of clinic visits was assessed by the use of primary care telephone clinics, primary care group visits, and the use of secure messaging to providers. Telephone clinics were classified as encounters with any primary care clinical staff including providers, RNs, LPNs, medical assistants, and clinical pharmacists. The use of secure messaging to providers was measured as the percentage of total assigned primary care patients sending 1 or more secure messages to primary care staff. Group visits were defined as shared medical appointments in primary care and primary care mental health integration clinics. Care management and coordination As indicators of care coordination, we used enrollment in programs designed to assist with care coordination, specifically home telemonitoring and enrollment in a home-based primary care program. As a marker for care coordination at the end of life, we measured visits to palliative care. Statistical analysis We evaluated bivariate comparisons between patient characteristics and with hospitalization and mortality, using the chi-square test for categorical variables and t tests for continuous variables. We constructed separate multivariate, logistic models to evaluate the association between the individual domains of primary care (access to care outside of clinic visits, continuity, and care coordination), and hospitalization or death adjusting for potentially confounding factors and clustering by facility. Covariates included demographic characteristics (age, gender, service connection, race/ethnicity), presence of chronic medical and psychiatric conditions (presence of mental health conditions [depression, posttraumatic stress disorder, substance use disorders] and Deyo-Charlson index), and the use of VHA health care services (number of visits to primary care and specialty clinics). Results for hospitalization were obtained from 2 models, one for patients younger than 65 years

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and another for patients older than 65 years. This was done because of potential differences between the 2 populations and also because 65 is the age at which patients become eligible for and use Medicare services (Liu et al., 2010). We analyzed VHA hospitalizations only: Medicare usage was not available for analysis. Our modeling strategy employed a split-sample approach, which provides stable estimates for large sample sizes (DeLong et al., 1988). The first sample included 50% of subjects who were randomly selected, and the second sample included the remaining 50%. To assess model discrimination, we compared C statistics for models generated from the 2 samples (Harrell et al., 1996). Because the models from the 2 samples had similar coefficients (data not shown) and the C-statistics were identical (0.72 for the hospitalization model and 0.79 for the mortality model), we combined the samples and reported results for the total group. RESULTS Of 4 328 714 Veterans assigned to a PCP as of April 2009, 3.3% (n = 145 142) died within the subsequent year, and 8.5% (n = 372 170) were hospitalized at a VHA facility. Most patients were older men who had coexisting medical and psychiatric conditions including hypertension (61.5%), diabetes (26.8%), and 2 or more mental health diagnoses (31.0%), most frequently depression (Table 1). Among those who were hospitalized, there was a high rate of mental illness (depression 24.6% and substance use disorder 13.9%). The percentage of visits Veterans made to their assigned PCP was strongly associated with a lower likelihood of admission in the subsequent year after statistical adjustment (Table 2). Using less than 50% of visits with the assigned PCP as a reference, Veterans younger than 65 years who made all primary care visits with the same provider had a lower odds of hospitalization (odds ratio [OR] = 0.88, 95% CI: 0.86-0.89). Similar results were noted for the Veterans older than 65 years. Indicators of expanded access to primary care outside of face-to-face clinic visits, including receipt

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Table 1. Population Characteristics

Total (N = 4 328 714) Demographics Age, mean, y Age > 65 y, % Male, % Race, % White Black Hispanic Other/unknown Service connection status > 50% Medical comorbidity Deyo-Charlson Index, mean, % Diabetes Obesity IHD COPD CHF Hypertension Mental health diagnoses Posttraumatic stress disorder Depression Substance use disorder Health care utilization No. of visits to primary care, mean Specialty care visits, mean Primary care continuity,a %

Elements of the patient-centered medical home associated with health outcomes among veterans: the role of primary care continuity, expanded access, and care coordination.

Care continuity, access, and coordination are important features of the patient-centered medical home model and have been emphasized in the Veterans H...
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