What value do teaching hospitals provide commercial beneficiaries when in an ACO?

OBJECTIVES: The number of commercial beneficiaries cared for by accountable care organizations (ACOs) is growing, but the literature examining their trends is nascent. STUDY DESIGN: We examined commercial claims data from 2019 to 2021 to compare beneficiaries attributed to participants in Medicare Shared Savings Program ACOs with and without a major teaching hospital. METHODS: We calculated mortality and spending by setting for each ACO type by year. RESULTS: Compared with per-beneficiary rates at nonteaching ACOs, major teaching ACOs have lower mortality rates by up to 2.2 percentage points depending on the patient age group, $283 lower inpatient spending, and lower emergency department utilization in inpatient (-0.008) and outpatient (-0.013) settings, as well as $146 higher overall outpatient spending. Upward trends in mortality and beneficiary risk scores across both ACO types show disruption to health outcomes during COVID-19. CONCLUSIONS: These results provide evidence that ACOs with major teaching hospitals may be more likely to achieve the value-based goals of ACOs. Means to accomplish those goals may include avoiding higher-intensity care and supporting access to lower-cost alternatives where clinically appropriate, such as reducing inpatient and emergency department stays by delivering timely, high-quality outpatient care.

Massachusetts Medicaid ACO Program May Have Improved Care Use And Quality For Pregnant And Postpartum Enrollees.

Value-based care models, such as Medicaid accountable care organizations (ACOs), have the potential to improve access to and quality of care for pregnant and postpartum Medicaid enrollees. We leveraged a natural experiment in Massachusetts to evaluate the effects of Medicaid ACOs on quality-of-care-sensitive measures and care use across the prenatal, delivery, and postpartum periods. Using all-payer claims data on Medicaid-covered live deliveries in Massachusetts, we used a difference-in-differences approach to compare measures before (the first quarter of 2016 through the fourth quarter of 2017) and after (the third quarter of 2018 through the fourth quarter of 2020) Medicaid ACO implementation among ACO and non-ACO patients. After three years of implementation, the Medicaid ACO was associated with statistically significant increases in the probability of a timely postpartum visit, postpartum depression screening, and number of all-cause office visits in the prenatal and postpartum periods, with no changes in severe maternal morbidity, preterm birth, postpartum glucose screening, or prenatal or postpartum emergency department visits. Changes in cesarean deliveries were inconclusive. Results suggest that implementing Medicaid ACOs in the thirty-eight states without them could improve maternal health care outpatient engagement, but alone it may be insufficient to improve maternal health outcomes.

Effects of Medicaid Accountable Care Organizations on children's access to and utilization of health services.

OBJECTIVE: To evaluate the effects of Medicaid Accountable Care Organizations (ACOs) on children's access to and utilization of health services. STUDY SETTING AND DESIGN: This study employs difference-in-differences models comparing ACO and non-ACO states from 2018 through 2021. Access measures are indicators for preventive and sick care sources, unmet healthcare needs, and having a personal doctor or nurse. Utilization measures are preventive and dental care, mental healthcare, specialist visits, emergency department visits, and hospital admissions. DATA SOURCES AND ANALYTIC SAMPLE: Secondary, de-identified data come from the 2016-2021 National Survey of Children's Health. The sample includes children with public insurance and ranges between 21,452 and 37,177 depending on the outcome. PRINCIPAL FINDINGS: Medicaid ACO implementation was associated with an increase in children's likelihood of having a personal doctor or nurse by about 4 percentage-points concentrated among states that implemented ACOs in 2018. Medicaid ACOs were also associated with an increase in specialist care use and decline in emergency visits by about 5 percentage-points (the latter being concentrated among states that implemented ACOs in 2020). There were no discernable or robust associations with other pediatric outcomes. CONCLUSIONS: There is mixed evidence on the associations of Medicaid ACOs with pediatric access and utilization outcomes. Examining effects over longer periods post-ACO implementation is important.

Telehealth Infrastructure, Accountable Care Organization, and Medicare Payment for Patients with Alzheimer's Disease and Related Dementia Living in Socially Vulnerable Areas.

Background: Structural social determinants of health have an accumulated negative impact on physical and mental health. Evidence is needed to understand whether emerging health information technology and innovative payment models can help address such structural social determinants for patients with complex health needs, such as Alzheimer's disease and related dementias (ADRD). Objective: This study aimed to test whether telehealth for care coordination and Accountable Care Organization (ACO) enrollment for residents in the most disadvantaged areas, particularly those with ADRD, was associated with reduced Medicare payment. Methods: The study used the merged data set of 2020 Centers for Medicare and Medicaid Services Medicare inpatient claims data, the Medicare Beneficiary Summary File, the Medicare Shared Savings Program ACO, the Center for Medicare and Medicaid Service's Social Vulnerability Index (SVI), and the American Hospital Annual Survey. Our study focused on community-dwelling Medicare fee-for-service beneficiaries aged 65 years and up. Cross-sectional analyses and generalized linear models (GLM) were implemented. Analyses were implemented from November 2023 to February 2024. Results: Medicare fee-for-service beneficiaries residing in SVI Q4 (i.e., the most vulnerable areas) reported significantly higher total Medicare costs and were least likely to be treated in hospitals that provided telehealth post-discharge services or have ACO affiliation. Meanwhile, the proportion of the population with ADRD was the highest in SVI Q4 compared with other SVI levels. The GLM regression results showed that hospital telehealth post-discharge infrastructure, patient ACO affiliation, SVI Q4, and ADRD were significantly associated with higher Medicare payments. However, coefficients of interaction terms among these factors were significantly negative. For example, the average interaction effect of telehealth post-discharge and ACO, SVI Q4, and ADRD on Medicare payment was -$1,766.2 (95% confidence interval: -$2,576.4 to -$976). Conclusions: Our results suggested that the combination of telehealth post-discharge and ACO financial incentives that promote care coordination is promising to reduce the Medicare cost burden among patients with ADRD living in socially vulnerable areas.

Defragmentation of care in complex patients with ESKD improves clinical outcomes.

OBJECTIVES: Given the problematic fragmentation of care for patients with end-stage kidney disease (ESKD), a kidney care organization and an integrated health system within a large accountable care organization partnered to best utilize their individual capabilities to collaborate around their shared patients in a coordinated care approach. Ultimately, the goal of the program is to allow care teams to achieve the triple aim of improving the patient experience, improving clinical outcomes, and reducing the total cost of health care. STUDY DESIGN: This is a retrospective examination of the first year of the Shared Patient Care Coordination (SPCC) program. METHODS: The analysis consisted of 2 parts. First, rates of hospitalizations and emergency department visits were compared between the SPCC patients and other patients of the integrated health system who had ESKD but did not participate in SPCC. Second, rates of clinical indicators-central venous catheter (CVC) use, home dialysis, advance care planning, and missed dialysis treatments-were benchmarked vs normative data taken by bootstrap sampling of the kidney care organization's patient population. RESULTS: Overall, dialysis patients participating in the SPCC program had a 15% lower rate of hospital admissions than those not participating ( P = .02). Additionally, the bootstrap analysis showed that by the second year, dialysis patients in the program had favorable rates (above the 95th percentile) of CVC use, dialysis treatment absenteeism, and completion of advance care plans. CONCLUSIONS: Enhanced and structured communication between dialysis providers and patient care teams provides a unique opportunity to coordinate patient-centered care and improve patient outcomes.

Accountable care organization initiatives to improve the cost and outcomes of specialty care.

OBJECTIVES: To assess initiatives to manage the cost and outcomes of specialty care in organizations that participate in Medicare accountable care organizations (ACOs). STUDY DESIGN: Cross-sectional analysis of 2023 ACO survey data. METHODS: Analysis of responses to a 12-question web-based survey from 101 respondents representing 174 ACOs participating in the Medicare Shared Savings Program or the Realizing Equity, Access, and Community Health ACO model in 2023. RESULTS: Improving specialist alignment was a high priority for 62% of the 101 respondents and a medium priority for 34%. Only 11% reported that employed specialists were highly aligned and 7% reported that contracted specialists were highly aligned. A subset of ACOs reported major efforts to engage specialists in quality improvement projects (38%) and to convene specialists to develop evidence-based care pathways (30%). They also reported supporting primary care physicians through providing specialist directories (44%), specialist e-consults (23%), and sharing specialist cost data (20%). The most common challenges reported were the influence of fee-for-service payment on specialist behavior (58%), lack of data to evaluate specialist performance (53%), and insufficient bandwidth or ACO resources to address specialist alignment (49%). CONCLUSIONS: Engaging specialists in accountable care is an emerging area for ACOs but one with numerous challenges. Making better data on specialist costs and outcomes available to Medicare ACOs is essential for accelerating progress.

ACO leakage among gynecologic cancer patients: Incidence, predictors, and impact on annual Medicare expenditure.

OBJECTIVE: To examine patterns of Accountable Care Organizations (ACO) leakage, the receipt of healthcare by ACO-assigned patients from institutions outside assigned ACO network, among patients with gynecologic cancer. ACO leakage was estimated as rates of patients seeking care external to their ACO assignment. Factors associated with ACO leakage were identified and cost differences within the first year of cancer diagnosis described. METHODS: Medicare 5% data (2013-2017) was used to quantify rates of leakage among gynecologic cancer patients with stable ACO assignment. Crude and multivariable adjusted risk ratios of ACO leakage risk factors were estimated using log-binomial regression models. Overall and cancer-specific spending differences by ACO leakage status were compared using Wilcoxon rank-sum test. RESULTS: Overall incidence of ACO leakage was 28.1% with highest leakage for outpatient care and uterine cancer patients. ACO leakage risk was 56% higher among Black relative to White patients, and 77% more for those in higher relative to lowest quintiles of median household income. Leakage decreased by 3% and 8% with each unit increase in ACO size and number of subspecialists, respectively. Healthcare costs were 19.5% higher for leakage patients. CONCLUSIONS: ACO leakage rates among gynecologic cancer patients was overall modest, with some regional and temporal variation, higher leakage for certain subgroups and substantially higher Medicare spending in inpatient and outpatient settings for patients with ACO leakage. These findings identify targets for further investigations and strategies to encourage oncologists to participate in ACOs and prevent increased health care costs associated with use of non-ACO providers.

Physicians in ACOs report greater documentation burden.

OBJECTIVES: First, to analyze the relationship between value-based payment (VBP) program participation and documentation burden among office-based physicians. Second, to analyze the relationship between specific VBP programs (eg, accountable care organizations [ACOs]) and documentation burden. STUDY DESIGN: Retrospective analyses of US office-based physicians in 2019 and 2021. METHODS: We used cross-sectional data from the National Electronic Health Records Survey to measure VBP program participation and our outcomes of reported electronic health record (EHR) documentation burden. We used ordinary least squares regression models adjusting for physician and practice characteristics to estimate the relationship between participation in any VBP program and EHR burden outcomes. We also estimated the relationship between participation in 6 distinct VBP programs and our outcomes to decompose the aggregate relationship into program-specific estimates. RESULTS: In adjusted analyses, participation in any VBP program was associated with 10.5% greater probability of reporting more than 1 hour per day of after-hours documentation time (P = .01), which corresponded to an estimated additional 11 minutes per day (P = .03). Program-specific estimates illustrated that ACO participation drove the aggregate relationship, with ACO participants reporting greater after-hours documentation time (18 additional minutes per day; P < .001), more difficulty documenting (30.6% more likely; P < .001), and more inappropriateness of time spent documenting (21.7% more likely; P < .001). CONCLUSIONS: Office-based physicians participating in ACOs report greater documentation burden across several measures; the same is not true for other VBP programs. Although many ACOs relax documentation requirements for reimbursement, documentation for quality reporting and risk adjustment may lead to a net increase in burden, especially for physicians exposed to numerous programs and payers.

The Impact of Medicaid Accountable Care Organizations on Health Care Utilization, Quality Measures, Health Outcomes and Costs from 2012 to 2023: A Scoping Review.

Most of the evidence regarding the success of ACOs is from the Medicare program. This review evaluates the impacts of ACOs within the Medicaid population. We identified 32 relevant studies published between 2012 and 2023 which analyzed the association of Medicaid ACOs and health care utilization (n = 21), quality measures (n = 18), health outcomes (n = 10), and cost reduction (n = 3). The results of our review regarding the effectiveness of Medicaid ACOs are mixed. Significant improvements included increased primary care visits, reduced admissions, and reduced inpatient stays. Cost reductions were reported in a few studies, and savings were largely dependent on length of attribution and years elapsed after ACO implementation. Adopting the ACO model for the Medicaid population brings some different challenges from those with the Medicare population, which may limit its success, particularly given differences in state Medicaid programs.

The Impact of Delivery Reform on Health Information Exchange with Behavioral Health Providers: Results from a National Representative Survey of Ambulatory Physicians.

Health information exchange (HIE) is an effective way to coordinate care, but HIE between health and behavioral health providers is limited. Recent delivery reform models, including the Accountable Care Organization (ACO) and Patient Centered Medical Home (PCMH) prioritize interprofessional collaboration, but little is known about their impact on behavioral health HIE. This study explores whether delivery reform participation affects behavioral health HIE among ambulatory health providers using pooled 2015-2019 data from the National Electronic Health Record Survey, a nationally representative survey of ambulatory physicians' technology use (n = 8,703). The independent variable in this analysis was provider participation in ACO, PCMH, Hybrid ACO-PCMH, or standard care. The dependent variable was HIE with behavioral health providers. Chi square analysis estimated unweighted rates of behavioral health HIE across reform models. Logistic regression estimated the impact of delivery reform participation on rates of behavioral health HIE. Unweighted estimates indicated that Hybrid ACO-PCMH providers had the highest rates of HIE (n = 330, 33%). In the fully adjust model, rates of HIE were higher among ACO (AOR = 2.66, p < .01), PCMH (AOR = 4.73, p < .001) and Hybrid ACO-PCMH participants (AOR = 5.55, p < .001) compared to standard care, but they did not significantly vary between delivery models. Physicians infrequently engage in HIE with behavioral health providers. Compared to standard care, higher rates of HIE were found across all models of delivery reform. More work is needed to identify common elements of delivery reform models that are most effective in supporting this behavior.

Preventive Primary Care in the Postpartum Year: The Role of Medicaid Delivery System Reform.

INTRODUCTION: Preventive and primary care in the postpartum year is critical for future health and may be increased by primary care focused delivery system reform including implementation of Medicaid Accountable Care Organizations (ACO). This study examined associations of Massachusetts Medicaid ACO implementation with preventive visits in the postpartum year. METHODS: The Massachusetts All-Payer Claims Database was used to identify births to privately-insured or Medicaid ACO-eligible individuals from January 1, 2016 to February 28, 2019. Comparing these groups before and after implementation, a propensity score weighted difference-in-difference design was used to analyze associations of Medicaid ACO implementation with any preventive care visit and any primary care physician (PCP) preventive visit within one year postpartum, controlling for other characteristics. Analyses were performed in 2023 and 2024. RESULTS: Of the 110,601 births in the study population, 35.5% had any preventive care visit and 23.0% had any preventive PCP visit in the year postpartum, with higher rates of preventive visits among privately-insured individuals. In adjusted difference-in-difference analyses, relative to the pre-period, there was a 2.7 percentage point (pp) decrease (95% confidence interval [CI]: -4.3pp, -1.2pp) and 3.5 pp decrease (95% CI: -4.9pp, -2.0pp) in use of any preventive visits and any PCP preventive visits, respectively, for Medicaid-insured versus privately-insured individuals after ACO implementation. CONCLUSIONS: Implementation of Massachusetts Medicaid ACOs was associated with decreases in receipt of preventive visits and preventive PCP visits for Medicaid-insured individuals relative to privately-insured individuals. Medicaid ACOs should consider potential implications of primary care access in the postpartum year for health across the lifecourse.

The mechanics of risk adjustment and incentives for coding intensity in Medicare.

OBJECTIVE: To study diagnosis coding intensity across Medicare programs, and to examine the impacts of changes in the risk model adopted by the Centers for Medicare and Medicaid Services (CMS) for 2024. DATA SOURCES AND STUDY SETTING: Claims and encounter data from the CMS data warehouse for Traditional Medicare (TM) beneficiaries and Medicare Advantage (MA) enrollees. STUDY DESIGN: We created cohorts of MA enrollees, TM beneficiaries attributed to Accountable Care Organizations (ACOs), and TM non-ACO beneficiaries. Using the 2019 Hierarchical Condition Category (HCC) software from CMS, we computed HCC prevalence and scores from base records, then computed incremental prevalence and scores from health risk assessments (HRA) and chart review (CR) records. DATA COLLECTION/EXTRACTION METHODS: We used CMS's 2019 random 20% sample of individuals and their 2018 diagnosis history, retaining those with 12 months of Parts A/B/D coverage in 2018. PRINCIPAL FINDINGS: Measured health risks for MA and TM ACO individuals were comparable in base records for propensity-score matched cohorts, while TM non-ACO beneficiaries had lower risk. Incremental health risk due to diagnoses in HRA records increased across coverage cohorts in line with incentives to maximize risk scores: +0.9% for TM non-ACO, +1.2% for TM ACO, and + 3.6% for MA. Including HRA and CR records, the MA risk scores increased by 9.8% in the matched cohort. We identify the HCC groups with the greatest sensitivity to these sources of coding intensity among MA enrollees, comparing those groups to the new model's areas of targeted change. CONCLUSIONS: Consistent with previous literature, we find increased health risk in MA associated with HRA and CR records. We also demonstrate the meaningful impacts of HRAs on health risk measurement for TM coverage cohorts. CMS's model changes have the potential to reduce coding intensity, but they do not target the full scope of hierarchies sensitive to coding intensity.

Longitudinal participation in delivery and payment reform programs among US Primary Care Organizations.

OBJECTIVE: To assess longitudinal primary care organization participation patterns in large-scale reform programs and identify organizational characteristics associated with multiprogram participation. DATA SOURCES: Secondary data analysis of national program participation data over an eight-year period (2009-2016). STUDY DESIGN: We conducted a retrospective, observational study by creating a unique set of data linkages (including Medicare and Medicaid Meaningful Use and Medicare Shared Savings Program Accountable Care Organization (MSSP ACO) participation from CMS, Patient-Centered Medical Home (PCMH) participation from the National Committee for Quality Assurance, and organizational characteristics) to measure longitudinal participation and identify what types of organizations participate in one or more of these reform programs. We used multivariate models to identify organizational characteristics that differentiate those that participate in none, one, or two-to-three programs. DATA EXTRACTION METHODS: We used Medicare claims to identify organizations that delivered primary care services (n = 56 ,287) and then linked organizations to program participation data and characteristics. PRINCIPAL FINDINGS: No program achieved more than 50% participation across the 56,287 organizations in a given year, and participation levels flattened or decreased in later years. 36% of organizations did not participate in any program over the eight-year study period; 50% participated in one; 13% in two; and 1% in all three. 14.31% of organizations participated in five or more years of Meaningful Use while 3.84% of organizations participated in five years of the MSSP ACO Program and 0.64% participated in at least five years of PCMH. Larger organizations, those with younger providers, those with more primary care providers, and those with larger Medicare patient panels were more likely to participate in more programs. CONCLUSIONS AND RELEVANCE: Primary care transformation via use of voluntary programs, each with their own participation requirements and approach to incentives, has failed to broadly engage primary care organizations. Those that have chosen to participate in multiple programs are likely those already providing high-quality care.

Dying with dementia in Medicare Advantage, Accountable Care Organizations, or traditional Medicare.

BACKGROUND/OBJECTIVE: Medicare Advantage (MA) and Accountable Care Organizations (ACOs) operate under incentives to reduce burdensome and costly care at the end of life. We compared end-of-life care for persons with dementia who are in MA, ACOs, or traditional Medicare (TM). DESIGN, SETTING, AND PARTICIPANTS: Retrospective study of decedents with dementia enrolled in MA, attributed to an ACO, or in TM. Decedents had a nursing home stay between 91 and 180 days prior to death, two or more functional impairments, and mild to severe cognitive impairment. MEASUREMENTS: Hospitalization, invasive mechanical ventilation (IMV) use, and in-hospital death in the last 30 days of life reported in Medicare billing. RESULTS: Among 370,094 persons with dementia, 93,801 (25.4%) were in MA (mean age [SD], 86.9 [7.7], 67.6% female), 39,586 (10.7%) were ACO attributed (mean age [SD], 87.2 [7.6], 67.3% female), and 236,707 (63.9%) were in TM (mean age [SD], 87.0 [7.8], 67.6% female). The proportion hospitalized in the last 30 days of life was higher among TM enrollees (27.9%) and those ACO attributed (28.1%) than among MA enrollees (20.5%, p ≤ 0.001). After adjustment for socio-demographics, cognitive and functional impairments, comorbidities, and Hospital Referral Region, adjusted odds of hospitalization in the 30 days prior to death was 0.72 (95% confidence interval [CI] 0.70-0.74) among MA enrollees and 1.05 (95% CI 1.02-1.09) among those attributed to ACOs relative to TM enrollees. Relative to TM, the adjusted odds of death in the hospital were 0.78 (95% CI 0.75-0.81) among MA enrollees and 1.02 (95% CI 0.96-1.08) for ACO participants. Dementia decedents in MA had a lower likelihood of IMV use (adjusted odds ratio 0.80, 95% CI 0.75-0.85) compared to TM. CONCLUSIONS: Among decedents with dementia, MA enrollees but not decedents in ACOs experienced less costly and potentially burdensome care compared with those with TM. Policy changes are needed for ACOs.

Effect of Community Health Workers on 30-Day Hospital Readmissions in an Accountable Care Organization Population: A Randomized Clinical Trial.

Importance: Value-based care within accountable care organizations (ACOs) has magnified the importance of reducing preventable hospital readmissions. Community health worker (CHW) interventions may address patients' unmet psychosocial and clinical care needs but have been underused in inpatient and postdischarge care. Objective: To determine if pairing hospitalized patients with ACO insurance with CHWs would reduce 30-day readmission rates. Design, Setting, and Participants: This randomized clinical trial was conducted in 6 general medicine hospital units within 1 academic medical center in Boston, Massachusetts. Participants included adults hospitalized from April 1, 2017, through March 31, 2019, who had ACO insurance and were at risk for 30-day readmission based on a hospital readmission algorithm. The main inclusion criterion was frequency of prior nonelective hospitalizations (≥2 in the past 3 months or ≥3 in the 12 months prior to enrollment). Data were analyzed from February 1, 2018, through March 3, 2021. Intervention: CHWs met with intervention participants prior to discharge and maintained contact for 30 days postdischarge to assist participants with clinical access and social resources via telephone calls, text messages, and field visits. CHWs additionally provided psychosocial support and health coaching, using motivational interviewing, goal-setting, and other behavioral strategies. The control group received usual care, which included routine care from primary care clinics and any outpatient referrals made by hospital case management or social work at the time of discharge. Main Outcomes and Measures: The primary outcome was 30-day hospital readmissions. Secondary outcomes included 30-day missed primary care physician or specialty appointments. Results: A total of 573 participants were enrolled, and 550 participants (mean [SD] age, 70.1 [15.7] years; 266 [48.4%] women) were included in analysis, with 277 participants randomized to the intervention group and 273 participants randomized to the control group. At baseline, participants had a mean (SD) of 3 (0.8) hospitalizations in the prior 12 months. There were 432 participants (78.5%) discharged home and 127 participants (23.1%) discharged to a short rehabilitation stay prior to returning home. Compared with participants in the control group, participants in the intervention group were less likely to be readmitted within 30 days (odds ratio [OR], 0.44; 95% CI, 0.28-0.90) and to miss clinic appointments within 30 days (OR, 0.56; 95% CI, 0.38-0.81). A post hoc subgroup analysis showed that compared with control participants, intervention participants discharged to rehabilitation had a reduction in readmissions (OR, 0.09; 95% CI, 0.03-0.31), but there was no significant reduction for those discharged home (OR, 0.68; 95% CI, 0.41-1.12). Conclusions and Relevance: This randomized clinical trial found that pairing ACO-insured inpatient adults with CHWs reduced readmissions and missed outpatient visits 30 days postdischarge. The effect was significant for those discharged to short-term rehabilitation but not for those discharged home. Trial Registration: ClinicalTrials.gov Identifier: NCT03085264.

The one-year impact of accountable care networks among Washington State employees.

OBJECTIVE: To estimate the impact of a new, two-sided risk model accountable care network (ACN) on Washington State employees and their families. DATA SOURCES/STUDY SETTING: Administrative data (January 2013-December 2016) on Washington State employees. STUDY DESIGN: We compared monthly health care utilization, health care intensity as measured through proxy pricing, and annual HEDIS quality metrics between the five intervention counties to 13 comparison counties, analyzed separately by age categories (ages 0-5, 6-18, 19-26, 18-64). DATA COLLECTION/EXTRACTION METHODS: We used difference-in-difference methods and generalized estimating equations to estimate the effects after 1 year of implementation for adults and children. PRINCIPAL FINDINGS: We estimate a 1-2 percentage point decrease in outpatient hospital visits due to the introduction of ACNs (adults: -1.8, P < .01; age 0-5: -1.2, P = .07; age 6-18: -1.2, P = .06; age 19-26; -1.2, P < .01). We find changes in primary and specialty care office visits; the direction of impact varies by age. Dependents age 19-26 were also responsive with inpatient admissions declines (-0.08 percentage points, P = .02). Despite changes in utilization, there was no evidence of changes in intensity of care and mixed results in the quality measures. CONCLUSIONS: Washington's state employee ACN introduction changed health care utilization patterns in the first year but was not as successful in improving quality.

The Effects of Accountable Care Organizations Forming Preferred Skilled Nursing Facility Networks on Market Share, Patient Composition, and Outcomes.

BACKGROUND: Through participation in payment reforms such as bundled payment and accountable care organizations (ACOs), hospitals are increasingly financially responsible for health care use and adverse health events occurring after hospital discharge. To improve management and coordination of postdischarge care, ACO hospitals are establishing a closer relationship with skilled nursing facilities (SNFs) through the formation of preferred SNF networks. RESEARCH DESIGN: We evaluated the effects of preferred SNF network formation on care patterns and outcomes. We included 10 ACOs that established preferred SNF networks between 2014 and 2015 in the sample. We first investigated whether hospitals "steer" patients to preferred SNFs by examining the percentage of patients sent to preferred SNFs within each hospital before and after network formation. We then used a difference-in-difference model with SNF fixed effects to evaluate the changes in patient composition and outcomes of preferred SNF patients from ACO hospitals after network formation relative to patients from other hospitals. RESULTS: We found that preferred network formation was not associated with higher market share or better outcomes for preferred SNF patients from ACO hospitals. However, we found a small increase in the average number of Elixhauser comorbidities for patients from ACO hospitals after network formation, relative to patients from non-ACO hospitals. CONCLUSIONS: After preferred SNF network formation, there is some evidence that ACO hospitals sent more complex patients to preferred SNFs, but there was no change in the volume of patients received by these SNFs. Furthermore, preferred network formation was not associated with improvement in patient outcomes.

Impact of the Medicare Shared Savings Program on utilization of mental health and substance use services by eligibility and race/ethnicity.

OBJECTIVE: To assess the impact of the Medicare Shared Savings Program (MSSP) ACOs on mental health and substance use services utilization and racial/ethnic disparities in care for these conditions. DATA SOURCES: Five percent random sample of Medicare claims from 2009 to 2016. STUDY DESIGN: We compared Medicare beneficiaries in MSSP ACOs to non-MSSP beneficiaries, stratifying analyses by Medicare eligibility (disability vs age 65+). We estimated difference-in-difference models of MSSP ACOs on mental health and substance use visits (outpatient and inpatient), medication fills, and adequate care for depression adjusting for age, sex, race/ethnicity, region, and chronic medical and behavioral health conditions. To examine the differential impact of MSSP on our outcomes by race/ethnicity, we used a difference-in-difference-in-differences (DDD) design. DATA COLLECTION/EXTRACTION METHODS: Not applicable. PRINCIPAL FINDINGS: MSSP ACOs were associated with small reductions in outpatient mental health (Coeff: -0.012, P < .001) and substance use (Coeff: -0.001, P < .01) visits in the disability population, and in adequate care for depression for both the disability- and age-eligible populations (Coeff: -0.028, P < .001; Coeff: -0.012, P < .001, respectively). MSSP ACO's were also associated with increases in psychotropic medications (Coeff: 0.007 and Coeff: 0.0213, for disability- and age-eligible populations, respectively, both P < .001) and reductions in inpatient mental health stays (Coeff:-0.004, P < .001, and Coeff:-0.0002, P < .01 for disability- and age-eligible populations, respectively) and substance use-related stays for disability-eligible populations (Coeff:-0.0005, P<.05). The MSSP effect on disparities varied depending on type of service. CONCLUSIONS: We found small reductions in outpatient and inpatient stays and in rates of adequate care for depression associated with MSSP ACOs. As MSSP ACOs are placed at more financial risk for population-based treatment, it will be important to include more robust behavioral health quality measures in their contracts and to monitor disparities in care.

The Effect of Medicare Shared Savings Program on Readmissions and Variations by Race/Ethnicity and Payer Status (December 9, 2020).

OBJECTIVE: Accountable care organizations in the Medicare Shared Savings Program (MSSP) in the United States attempt to reduce cost and improve quality for their patients by improving care coordination across care settings. We examined the impact of hospital participation in the MSSP on 30-day readmissions for several groups of Medicare inpatients, and by race/ethnicity and payer status. MAIN DATA SOURCE: A 2010-2016 Medicare Provider Analysis and Review files. RESEARCH DESIGN: With propensity score matched sample of MSSP and non-MSSP-participating hospitals, patient-level linear probability models with difference-in-differences approach were used to compare the changes in readmission rates for Medicare fee-for-service patients initially admitted for ischemic stroke, hip fracture, or total joint arthroplasty in MSSP-participating hospitals with non-MSSP-participating hospitals as well as to compare the changes in disparities in readmission rates over time. PRINCIPAL FINDINGS: Hospital participation in MSSP was associated with further reduced readmission rate by 1.1 percentage points (95% confidence interval: -0.02 to 0.00, P<0.05) and 1.5 percentage points (95% confidence interval: -0.03 to 0.00, P=0.08) for ischemic stroke and hip fracture cohorts, respectively, compared with non-MSSP-participating hospitals, after the third year of hospital participation in the MSSP. There was no evidence that MSSP had an impact on racial/ethnic disparities, but increased disparity by payer status (dual vs. Medicare-only) was observed. These findings together suggest that MSSP accountable care organizations may take at least 3 years to achieve reduced readmissions and may increase disparities by payer status.

Impact of a commercial accountable care organization on prescription drugs.

OBJECTIVE: To determine the long-run impact of a commercial accountable care organization (ACO) on prescription drug spending, utilization, and related quality of care. DATA SOURCES/STUDY SETTING: California Public Employees' Retirement System (CalPERS) health maintenance organization (HMO) member enrollment data and pharmacy benefit claims, including both retail and mail-order generic and brand-name prescription drugs. STUDY DESIGN: We applied a longitudinal retrospective cohort study design and propensity-weighted difference-in-differences regression models. We examined the relative changes in outcome measures between two ACO cohorts and one non-ACO cohort before and after the ACO implementation in 2010. The ACO directed provider prescribing patterns toward generic substitution for brand-name prescription drugs to maximize shared savings in pharmacy spending. DATA COLLECTION/EXTRACTION METHODS: The study sample included members continuously enrolled in a CalPERS commercial HMO from 2008 through 2014 in the Sacramento area. PRINCIPAL FINDINGS: The cohort differences in baseline characteristics of 40 483 study participants were insignificant after propensity-weighting adjustment. The ACO enrollees had no significant differential changes in either all or most of the five years of the ACO operation for the following measures: (1) average total spending and (2) average total scripts filled and days supplied on either generic or brand-name prescription drugs, or the two combined; (3) average generic shares of total prescription drug spending, scripts filled or days supplied; (4) annual rates of 10 outpatient process quality of care metrics for medication prescribing or adherence. CONCLUSIONS: Participation in the commercial ACO was associated with negligible differential changes in prescription drug spending, utilization, and related quality of care measures. Capped financial risk-sharing and increased generics substitution for brand names are not enough to produce tangible performance improvement in ACOs. Measures to increase provider financial risk-sharing shares and lower brand-name drug prices are needed.