Medicare Accountable Care Organizations Research Articles

High-need beneficiary enrollment patterns in Medicare Advantage and traditional Medicare.

High-need Medicare beneficiaries require elevated levels of care and coordination to manage their conditions. We evaluated the extent to which high-need beneficiaries enrolled in Medicare Advantage (MA) or traditional Medicare (TM) accountable care organizations (ACOs) relative to TM non-ACOs. Using Medicare claims and MA encounter data, we identified 3 groups of high-need beneficiaries: (1) individuals younger than 65 years with a disability or end-stage kidney disease, (2) frail individuals, and (3) older individuals with major complex or multiple noncomplex chronic conditions. For comparison, we included non-high-need beneficiaries in the analysis, including those with minor complex chronic conditions. Descriptive analysis of Medicare enrollment patterns and beneficiary characteristics of high-need and other beneficiaries between 2016 and 2019. In 2019, high-need beneficiaries accounted for 18 million or 32% of enrollees in TM and MA, an increase of approximately 1 million since 2016, driven by growth in MA. A larger share of beneficiaries in TM ACOs was high need (38%) compared with MA (24%). Although the totalcount of high-need beneficiaries in TM remained stable from 2016 to 2019, ACOs saw an increase of almost 1.5 million high-need beneficiaries (39% increase), and TM non-ACOs saw a decrease of 1.9 million (23% decrease). We found that high-need beneficiaries were more likely to be in TM non-ACOs than in MA through 2019. However, an increasing number of these beneficiaries are enrolling in MA or aligned with a TM ACO. A projected increase in the population of older adults will increase the economic burden of caring for high-need individuals.

Classification Algorithm to Distinguish Between Type 1 and Type 2 Myocardial Infarction in Administrative Claims Data.

Type 2 myocardial infarction (T2MI) and type 1 myocardial infarction (T1MI) differ with respect to demographics, comorbidities, treatments, and clinical outcomes. Reliable quality and outcomes assessment depends on the ability to distinguish between T1MI and T2MI in administrative claims data. As such, we aimed to develop a classification algorithm to distinguish between T1MI and T2MI that could be applied to claims data. Using data for beneficiaries in a Medicare accountable care organization contract in a large health care system in New England, we examined the distribution of MI diagnosis codes between 2018 to 2021 and the patterns of care and coding for beneficiaries with a hospital discharge diagnosis International Classification of Diseases, Tenth Revision code for T2MI, compared with those for T1MI. We then assessed the probability that each hospitalization was for a T2MI versus T1MI and examined care occurring in 2017 before the introduction of the T2MI code. After application of inclusion and exclusion criteria, 7759 hospitalizations for myocardial infarction remained (46.5% T1MI and 53.5% T2MI; mean age, 79±10.3 years; 47% female). In the classification algorithm, female gender (odds ratio, 1.26 [95% CI, 1.11-1.44]), Black race relative to White race (odds ratio, 2.48 [95% CI, 1.76-3.48]), and diagnoses of COVID-19 (odds ratio, 1.74 [95% CI, 1.11-2.71]) or hypertensive emergency (odds ratio, 1.46 [95% CI, 1.00-2.14]) were associated with higher odds of the hospitalization being for T2MI versus T1MI. When applied to the testing sample, the C-statistic of the full model was 0.83. Comparison of classified T2MI and observed T2MI suggest the possibility of substantial misclassification both before and after the T2MI code. A simple classification algorithm appears to be able to differentiate between hospitalizations for T1MI and T2MI before and after the T2MI code was introduced. This could facilitate more accurate longitudinal assessments of acute myocardial infarction quality and outcomes.

Cost Reduction and Utilization Patterns in a Medicare Accountable Care Organization Using Home-Based Palliative Care Services.

Accountable care organizations (ACOs) are often tasked with helping providers to deliver care efficiently and with higher quality outcomes. For an ACO to succeed in delivering efficient care, it is important to direct resources toward patients who exhibit the greatest levels of opportunity while focusing attention toward mitigating their needs. Home-based palliative care (HBPC) services are known to address patient needs for those with serious illness while decreasing the total cost of care (TCC). In this retrospective review, ACO researchers reviewed cost, quality, and utilization patterns for 3418 beneficiaries within a Medicare Shared Saving Program approaching the end of life comparing decedents who received HBPC versus those who did not receive the service. Those individuals who received HBPC services were significantly less likely to be hospitalized (51% reduction in the HBPC group), more likely to use hospice (70% vs. 43%; P = 0.001), and their TCC was less than that of those who did not receive the service ($27,203 vs. $36,089: P = 0.0163). Although more research needs to be done to understand the specific components of care delivery that are helpful in decreasing unnecessary utilization, in this retrospective review in an accountable care population, HBPC is associated with a significant decrease in cost and utilization in a population approaching end of life.

All-payer value-based contracting in organizations with Medicare ACOs.

To measure the prevalence of non-Medicare value-based contracting and participation in contracts with downside risk among organizations participating in the Medicare Shared Savings Program (MSSP). Cross-sectional analysis of 2022 accountable care organization (ACO) survey. The author analyzed surveys from 100 organizations participating in the MSSP that reported the number of covered lives they have in value-based contracts in traditional Medicare (ACOs), Medicare Advantage (MA), commercial payers, Medicaid managed care organizations, Medicaid, and direct-to-employer arrangements. We analyzed the distribution of covered lives across shared-savings, shared-risk, and full-risk contracts and analyzed changes between 2018 and 2022. Respondents reported 15.5 million covered lives in value-based contracts. All respondents have Medicare ACO contracts, and roughly 75% reported value-based contracts with commercial and MA plans. Approximately one-third reported such contracts with Medicaid managed care plans. Seventy percent of covered lives in respondents' Medicare ACO contracts included downside risk for losses compared with 51% of lives in commercial plans and 45% in MA plans. Compared with a similar 2018 survey, the proportion of respondents in value-based MA contracts doubled, and the proportion in commercial contracts rose by half. Organizations that participate in Medicare ACO models have substantially increased their participation in value-based contracts with other payers. They reported a higher proportion of Medicare ACO covered lives in downside risk arrangements than in commercial or MA contracts.

Dialysis costs for a health system participating in value-based care.

Unplanned "crash" dialysis starts are associated with worse outcomes and higher costs, a challenging problem for health systems participating in value-based care (VBC). We examined expenditures and utilization associated with these events in a large health system. Retrospective, single-center study at Cleveland Clinic, a large, integrated health system participating in VBC contracts, including a Medicare accountable care organization. We analyzed beneficiaries who transitioned to dialysis between 2017 and 2020. Crash starts involved initiating inpatient hemodialysis (HD) with a central venous catheter (CVC). Optimal starts were initiated with either home dialysis or outpatient HD without a CVC. Suboptimal starts were initiated with outpatient HD with a CVC or inpatient HD without a CVC. A total of 495 patients initiated chronic dialysis: 260 crash starts, 130 optimal starts, and 105 suboptimal starts. Median predialysis 12-month cost was $67,059 for crash starts, $17,891 for optimal starts, and $7633 for suboptimal starts (P < .001). Median postdialysis 12-month cost was $71,992 for crash starts, $55,427 for optimal starts, and $72,032 for suboptimal starts (P = .001). Predialysis inpatient admission per 1000 beneficiaries was 1236 per 1000 for crash starts vs 273 per 1000 for optimal starts and 170 per 1000 for suboptimal starts (P < .001). Postdialysis inpatient admission for crash starts was 853 per 1000 vs 291 per 1000 for optimal starts and 184 per 1000 for suboptimal starts (P < .001). In a major health system, crash starts demonstrated the highest cost and hospital utilization, a pattern that persisted after dialysis initiation. Developing strategies to promote optimal starts will improve VBC contract performance.

Provision of Digital Health Technologies for Opioid Use Disorder Treatment by US Health Care Organizations

Digital health technologies may expand organizational capacity to treat opioid use disorder (OUD). However, it remains unclear whether these technologies serve as substitutes for or complements to traditional substance use disorder (SUD) treatment resources in health care organizations. To characterize the use of patient-facing digital health technologies for OUD by US organizations with accountable care organization (ACO) contracts. This cross-sectional study analyzed responses to the 2022 National Survey of Accountable Care Organizations (NSACO), collected between October 1, 2021, and June 30, 2022, from US organizations with Medicare and Medicaid ACO contracts. Data analysis was performed between December 15, 2022, and January 6, 2023. Treatment resources for SUD (eg, an addiction medicine specialist, sufficient staff to treat SUD, medications for OUD, a specialty SUD treatment facility, a registry to identify patients with OUD, or a registry to track mental health for patients with OUD) and organizational characteristics (eg, organization type, Medicaid ACO contract). The main outcomes included survey-reported use of 3 categories of digital health technologies for OUD: remote mental health therapy and tracking, virtual peer recovery support programs, and digital recovery support for adjuvant cognitive behavior therapy (CBT). Statistical analysis was conducted using descriptive statistics and multivariable logistic regression models. Overall, 276 of 505 organizations responded to the NSACO (54.7% response rate), with a total of 304 respondents. Of these, 161 (53.1%) were from a hospital or health system, 74 (24.2%) were from a physician- or medical group-led organization, and 23 (7.8%) were from a safety-net organization. One-third of respondents (101 [33.5%]) reported that their organization used at least 1 of the 3 digital health technology categories, including remote mental health therapy and tracking (80 [26.5%]), virtual peer recovery support programs (46 [15.1%]), and digital recovery support for adjuvant CBT (27 [9.0%]). In an adjusted analysis, organizations with an addiction medicine specialist (average marginal effect [SE], 32.3 [4.7] percentage points; P < .001) or a registry to track mental health (average marginal effect [SE], 27.2 [3.8] percentage points; P < .001) were more likely to use at least 1 category of technology compared with otherwise similar organizations lacking these capabilities. In this cross-sectional study of 276 organizations with ACO contracts, organizations used patient-facing digital health technologies for OUD as complements to available SUD treatment capabilities rather than as substitutes for unavailable resources. Future studies should examine implementation facilitators to realize the potential of emerging technologies to support organizations facing health care practitioner shortages and other barriers to OUD treatment delivery.

Risk Selection and Care Fragmentation at Medicare Accountable Care Organizations for Patients With Dementia.

Patients with dementia are a growing and vulnerable population within Medicare. Accountable care organizations (ACOs) are becoming Medicare's dominant care model, but ACO enrollment and care patterns for patients with dementia are unknown. The aim of this study was to compare differences in ACO enrollment for patients with versus without dementia, and in risk profiles and ambulatory care among patients with dementia by ACO enrollment status. Cohort study assessing the relationships between patient dementia, following-year ACO enrollment, and ambulatory care patterns. A total of 13,362 (weighted: 45, 499,049) person-years for patients [2761 (weighted: 6,312,304) for dementia patients] ages 65 years and above in the 2015-2019 Medicare Current Beneficiary Survey. We assessed differences in ACO enrollment rates for patients with versus without dementia, and in dementia-relevant ambulatory care visit rates and validated care fragmentation indices among patients with dementia by ACO enrollment status. Patients with versus without dementia were less likely to be enrolled in (38.3% vs. 44.6%, P<0.001), and more likely to exit (21.1% vs. 13.7%, P<0.01) ACOs. Among patients with dementia, those enrolled versus not enrolled in ACOs had a more favorable social and health risk profile on 6 of 16 measures (P<0.05). There were no differences in rates of dementia-relevant, primary, or specialty care visits. ACO enrollment was associated with 45.7% higher wellness visit rates (P<0.001), and 13.4% more fragmented primary care (P<0.01) spread across 8.7% more distinct physicians (P<0.05). Medicare ACOs are less likely to enroll and retain patients with dementia than other patients and provide more fragmented primary care without providing additional dementia-relevant ambulatory care visits.

Telehealth medication management and health care spending in a Medicare Accountable Care Organization.

BACKGROUND: Value-based care is an opportunity for medication optimization services to improve medication management and reduce health care spending. The reach of these services may be extended through telehealth. However, as health care systems and payers grapple with the long-term financing of telehealth, real-world assessments are needed to evaluate the potential economic impact of pharmacy-driven telehealth services. OBJECTIVE: To evaluate the impact of a scalable pharmacist-driven telehealth intervention to improve medication management on health care spending for clinically complex patients who were enrolled in a Medicare Next Generation Accountable Care Organization. METHODS: Data for this pretest-posttest nonequivalent group design study came from Medicare claims from 2015 to 2020 and linked pharmacist care activity data derived from the electronic medical record. Patients in the intervention group were identified as those who received the telehealth medication management service. Patients in the control group were offered the service and refused or could not be contacted. The primary outcome was total medical spending over a 6-month period, and impact was assessed using a covariate-adjusted difference-in-difference model. RESULTS: There were 581 patients who received the intervention and 1,765 who served as controls. The telehealth intervention reduced total medical spending by $2,331.85 per patient over the first 6 months of the service ($388.50 per month; P = 0.0261). Across a range of estimates for the cost of service delivery, we find a return on investment of 3.6:1 to 5.2:1. CONCLUSIONS: The $388.50 monthly savings found in this study represent a substantial reduction in health care spending and emphasize the opportunity for telehealth delivery of medication management services to improve value as a part of alternative payment models. DISCLOSURES: This study was funded by the UNC Health Care Department of Pharmacy. Dr Urick has received personal fees from Pharmacy Quality Solutions and Cardinal Health. Drs Peters, Vest, Colmenares, Foushee, and DeFalco are employees of UNC Health Care Department of Pharmacy. Mr Easter received a Co-PI grant from NACDS Foundation to implement Community-based Value Care Initiative (CVCI) in a community pharmacy setting. He also received a grant to Eshelman School of Pharmacy. He has an individual consulting agreement with digital health company Truentity Health to provide go to market strategy for medication management services. He also has stock options from Truentity Health as a component of the consulting agreement. Dr Foushee has a leadership or fiduciary role at Member-At-Large and the Ambulatory Care Academy of the North Carolina Association of Pharmacists. At the time this work was conducted, Dr Urick, Dr Pathak, and Dr Blanchard were all employees of the UNC Eshelman School of Pharmacy.

Changes in Medicare Accountable Care Organization Spending, Utilization, and Quality Performance 2 Years Into the COVID-19 Pandemic

This cohort study uses data from the Medicare Shared Savings Program to assess changes in spending, utilization, and quality performance from before the COVID-19 pandemic (2019) to year 2 of the pandemic (2021).

Evaluating Inpatient Hospital Charges Associated With Trauma Service Patients Participating in an Accountable Care Organization.

The Medicare Accountable Care Organization (ACO) Program has created a vehicle for providers who practice cost containment and exceed quality for the Medicare population. The success of ACO's nationwide have been well documented. However, there is little research evaluating if there is a cost saving benefit in trauma care with respect to participating in an ACO. Thus, the primary objective of this study was to evaluate inpatient hospital charges associated with trauma service utilization of patients participating in the ACO compared to non-ACO patients. This case-control retrospective study includes a comparison of inpatients charges of ACO patients (cases) and general trauma patients (controls) presenting to our trauma center in Staten Island, New York from January 1st, 2019 to December 31st, 2021. A 1:1 matching of case to control was performed based on age, sex, race, and injury severity score. Statistical analysis was performed with IBM SPSS, with P < .05 as significant. A total of 80 patients were included in the ACO cohort and 80 matched in the General Trauma cohort. Patient demographics were similar. Comorbidities were similar with the exception of a higher in incidence of hypertension (75.0% vs 47.5%, P < .001) and cardiac disease (35.0% vs 17.5%, P = .012) in the ACO cohort. Both the ACO and general trauma cohort had similar Injury Severity Scores, number of visits and lenght of stay. Both charge total ($76 148.93 vs $70 916.82, P = .630) receipt total ($15 080.26 vs $14 180, P = .662) charges were similar between ACO and General Trauma patients. In spite of increased incidence of hypertension and cardiac disease in ACO trauma patients, mean Injury Severity Score, number of visits, length of hospital stay, ICU admission rate and charge total was similar compared to general trauma patients presenting to our Level 1 Adult Trauma Center.

Association of Medicare Beneficiary and Hospital Accountable Care Organization Alignment With Surgical Cost Savings

Although Medicare accountable care organizations (ACOs) account for half of program expenditures, whether ACOs are associated with surgical spending warrants further study. To assess whether greater beneficiary-hospital ACO alignment was associated with lower surgical episode costs. This retrospective cohort study was conducted between 2020 and 2022 using US Medicare data from a 20% random sample of beneficiaries. Individuals 18 years of age and older and without kidney failure who had a surgical admission between 2008 and 2015 were included. For each study year, distinction was made between beneficiaries assigned to an ACO and those who were not, as well as between admissions to ACO-participating and nonparticipating hospitals. Time-varying binary indicators for beneficiary ACO assignment and hospital ACO participation and an interaction between them. Ninety-day, price-standardized total episode payments. Multivariable 2-way fixed-effects models were estimated. During the study period, 2 797 337 surgical admissions (6% of which involved ACO-assigned beneficiaries) occurred at 3427 hospitals (17% ACO participating). Total Medicare payments for 90-day surgical episodes were lowest when ACO-assigned beneficiaries underwent surgery at a hospital participating in the same ACO as the beneficiary ($26 635 [95% CI, $26 426-$26 844]). The highest payments were for unassigned beneficiaries treated at participating hospitals ($27 373 [95% CI, $27 232-$27 514]) or nonparticipating hospitals ($27 303 [95% CI, $27 291-$27 314]). Assigned beneficiaries treated at hospitals participating in a different ACO and assigned beneficiaries treated at nonparticipating hospitals had similar payments (for participating hospitals, $27 003 [95% CI, $26 739-$27 267] and for nonparticipating hospitals, $26 928 [95% CI, $26 796-$27 059]). A notable factor in the observed differences in surgical episode costs was lower spending on postacute care services. In this cohort study evaluating hospital and beneficiary ACO alignment and surgical spending, savings were noted for beneficiaries treated at hospitals in the same ACO. Allowing ACOs to encourage or require surgical procedures in their own hospitals could lower Medicare spending on surgery.

Changes in spending, utilization, and quality of care among Medicare accountable care organizations during the COVID-19 pandemic

The COVID pandemic disrupted health care spending and utilization, and the Medicare Shared Savings Program (MSSP), Medicare’s largest value-based payment model with 11.2 million assigned beneficiaries, was no exception. Despite COVID, the 513 accountable care organizations (ACO) in MSSP returned a program record $1.9 billion in net savings to Medicare in 2020. To understand the extent of COVID’s impact on MSSP cost and quality, we describe how ACO spending changed in 2020 and further analyze changes in measured quality and utilization. We found that non-COVID per capita spending in MSSP fell by 8.3 percent from $11,496 to $10,537 (95% confidence interval(CI),-1,223.8 to-695.4, p<0.001), driven by 14.6% and 7.5% reductions in per capita acute inpatient and outpatient spending, respectively. Utilization fell across inpatient, emergency, and outpatient settings. On quality metrics, preventive screening rates remained stable or improved, while control of diabetes and blood pressure worsened. Large reductions in non-COVID utilization helped ACOs succeed financially in 2020, but worsening chronic disease measures are concerning. The appropriateness of the benchmark methodology and exclusion of COVID-related spending, especially as the virus approaches endemicity, should be revisited to ensure bonus payments reflect advances in care delivery and health outcomes rather than COVID-related shifts in spending and utilization patterns.

ACO Participation Associated With Decreased Spending For Medicare Beneficiaries With Serious Mental Illness

Serious mental illness (SMI) is a major source of suffering among Medicare beneficiaries. To date, limited evidence exists evaluating whether Medicare accountable care organizations (ACOs) are associated with decreased spending among people with SMI. Using national Medicare data from the period 2009-17, we performed difference-in-differences analyses evaluating changes in spending and use associated with enrollment in the Medicare Shared Savings Program (MSSP) among beneficiaries with SMI. After five years, participation in MSSP ACOs was associated with small savings for beneficiaries with SMI (-$233 per person per year) in total health care spending, primarily related to savings from chronic medical conditions (excluding mental health; -$227 per person per year) and not from savings related to mental health services (-$6 per person per year). Savings were driven by reductions in acute and postacute care for medical conditions. Further work is needed to ensure that Medicare ACOs invest in strategies to reduce potentially unnecessary care related to mental health disorders and to improve health outcomes.

Medicare Accountable Care Organizations: Post-acute Care Use and Post-surgical Outcomes in Urologic Cancer Surgery

To evaluate association between Medicare accountable care organizations (ACOs) participation of hospitals on post-acute care (PAC) use and spending, and post-surgical outcomes in Medicare beneficiaries undergoing urologic cancer surgeries. Despite increasing prevalence of urologic cancer and surgical care contributing to a large proportion of total health care costs, and recent Medicare payment reforms such as accountable care organizations, the role of ACOs in urologic cancer care has been unexplored. We conducted a longitudinal analysis of 2011-2017 Medicare claims data to compare post-surgical outcomes between Medicare ACO and non-ACO patients before and after implementation of Medicare shared savings program (MSSP). Our outcomes of interest were Post-acute care (PAC) use (overall, institutional, and home health), Skilled Nursing Facility (SNF) length of stay and Medicare spending for SNF patients, 30-day and 90-day unplanned readmissions and complications after index procedure. Study sample included a total of 334,514 Medicare patients undergoing bladder, prostate, kidney cancer surgeries at 524 Medicare ACO and 2066 non-ACO hospitals. For bladder cancer surgery, Medicare ACO participation was associated with significantly reduced overall post-acute care use, but not with changes in readmission or complication rate. For prostate cancer and kidney cancer surgery, we found no significant association between hospital participation in Medicare ACOs and PAC use or post-surgical outcomes. Hospital participation in MSSP ACOs leads to lower post-acute care use without compromising patient outcomes for Medicare beneficiaries undergoing bladder cancer surgery. Future research is needed to understand longer-term impact of ACO participation on urologic cancer surgery outcomes.

Impactability Modeling for Reducing Medicare Accountable Care Organization Payments and Hospital Events in High-Need High-Cost Patients: Longitudinal Cohort Study.

BackgroundImpactability modeling promises to help solve the nationwide crisis in caring for high-need high-cost patients by matching specific case management programs with patients using a “benefit” or “impactability” score, but there are limitations in tailoring each model to a specific program and population.ObjectiveWe evaluated the impact on Medicare accountable care organization savings from developing a benefit score for patients enrolled in a historic case management program, prospectively implementing the score, and evaluating the results in a new case management program.MethodsWe conducted a longitudinal cohort study of 76,140 patients in a Medicare accountable care organization with multiple before-and-after measures of the outcome, using linked electronic health records and Medicare claims data from 2012 to 2019. There were 489 patients in the historic case management program, with 1550 matched comparison patients, and 830 patients in the new program, with 2368 matched comparison patients. The historic program targeted high-risk patients and assigned a centrally located registered nurse and social worker to each patient. The new program targeted high- and moderate-risk patients and assigned a nurse physically located in a primary care clinic. Our primary outcomes were any unplanned hospital events (admissions, observation stays, and emergency department visits), count of event-days, and Medicare payments.ResultsIn the historic program, as expected, high-benefit patients enrolled in case management had fewer events, fewer event-days, and an average US $1.15 million reduction in Medicare payments per 100 patients over the subsequent year when compared with the findings in matched comparison patients. For the new program, high-benefit high-risk patients enrolled in case management had fewer events, while high-benefit moderate-risk patients enrolled in case management did not differ from matched comparison patients.ConclusionsAlthough there was evidence that a benefit score could be extended to a new case management program for similar (ie, high-risk) patients, there was no evidence that it could be extended to a moderate-risk population. Extending a score to a new program and population should include evaluation of program outcomes within key subgroups. With increased attention on value-based care, policy makers and measure developers should consider ways to incorporate impactability modeling into program design and evaluation.

Using a home time measure to differentiate ACO performance for seriously ill populations.

Alternative Payment Models (APMs) piloted by the Centers for Medicare and Medicaid Services (CMS) such as ACO Realizing Equity, Access and Community Health (REACH) seek to improve care and quality of life among seriously ill populations (SIP). Days at Home (DAH) was proposed for use in this model to evaluate organizational performance. It is important to assess the utility and feasibility of person-centered outcomes measures, such as DAH, as CMS seeks to advance care models for seriously ill beneficiaries. We leverage existing Accountable Care Organization (ACO) contracts to evaluate the feasibility of ACO-level DAH measure and examine characteristics associated with ACOs with more DAH. We calculated DAH for Medicare fee-for-service beneficiaries aged 68 and over who were retrospectively attributed to a Medicare ACO between 2014 and 2018 and met the seriously ill criteria. We then aggregated to the ACO level DAH for each ACO's seriously ill beneficiaries and risk-adjusted this aggregated measure. Finally, we evaluated associations between risk-adjusted DAH per person-year and ACO, beneficiary, and market characteristics. ACOs' seriously ill beneficiaries spent an average of 349.3 risk-adjusted DAH per person-year. Risk-adjusted ACO variation, defined as the interquartile range, was 4.21 days (IQR=347.32-351.53). Beneficiaries of ACOs are composed of a less racially diverse beneficiary cohort, opting for two-sided risk models, and operating in markets with fewer hospital and Skilled Nursing Facility beds had more DAH. Substantial variation across ACOs in the DAH measure for seriously ill beneficiaries suggests the measure can differentiate between high and low performing provider groups. Key to the success of the metric is accurate risk adjustment to ensure providers have adequate resources to care for seriously ill beneficiaries. Organizational factors, such as the ACO size and level of risk, are strongly associated with more days at home.

Medicare accountable care organization characteristics associated with participation in 2-sided risk.

To examine the associations of accountable care organization (ACO) characteristics with the likelihood of participation in 2-sided risk tracks in the Medicare Shared Savings Program (SSP). CMS ACO Public Use Files and Provider-Level Research Identifiable Files were used to trace Medicare ACOs' participation in the SSP between 2012 and 2020 and measure ACO characteristics, including size, rurality of the service area, affiliation with supporting organizations, program experience, and performance. Logistic regression and survival analysis were used to test the associations between ACO characteristics and the probability of ACOs initially participating in or subsequently switching to 2-sided risk tracks. Among the 624 Medicare SSP ACOs that started between 2012 and 2017, 26 participated in 2-sided risk tracks in their initial contracts and 95 switched to 2-sided risk tracks subsequently. ACO characteristics were not significantly associated with the probability of participating in 2-sided risk tracks in initial contracts. ACO size, affiliation with supporting organizations, and performance were positively associated with the likelihood of switching to 2-sided risk. Rural ACOs were less likely to switch to 2-sided risk than their urban counterparts. Small and rural ACOs are less prepared to transition into 2-sided risk swiftly.

Association Between Organizational Quality and Out-of-Network Primary Care Among Accountable Care Organizations That Care for High vs Low Proportions of Patients of Racial and Ethnic Minority Groups

Medicare accountable care organizations (ACOs) that disproportionately care for patients of racial and ethnic minority groups deliver lower quality care than those that do not, potentially owing to differences in out-of-network primary care among them. To examine how organizational quality is associated with out-of-network primary care among ACOs that care for high vs low proportions of patients of racial and ethnic minority groups. A retrospective cohort study was conducted between March 2019 and October 2021 using claims data (2013 to 2016) from a national sample of Medicare beneficiaries. Among beneficiaries who were assigned to 1 of 528 Medicare ACOs, a distinction was made between those treated by organizations that cared for high (vs low) proportions of patients of racial and ethnic minority groups. For each ACO, the amount of out-of-network primary care that it delivered annually was determined. Multivariable models were fit to evaluate how the quality of care that beneficiaries received varied by the proportion of care provided to patients of racial and ethnic minority groups by the ACO and its amount of out-of-network primary care. The degree of care provided to patients of racial and ethnic minority groups by the ACO and its amount of out-of-network primary care. The ACO quality assessed with 5 preventive care services and 4 utilization metrics. Among 3 955 951 beneficiary-years (2 320 429 [58.7%] women; 71 218 [1.8%] Asian, 267 684 [6.8%] Black, 44 059 [1.1%] Hispanic, 4922 [0.1%] North American Native, and 3 468 987 [87.7%] White individuals and 56 157 [1.4%] of Other race and ethnicity), those assigned to ACOs serving many patients of racial and ethnic minority groups at the mean level of out-of-network primary care were less likely than those assigned to ACOs serving fewer patients of racial and ethnic minority groups to receive diabetic retinal examinations (predicted probability, 49.4% [95%CI, 49.0%-49.7%] vs 51.6% [95% CI, 51.5%-51.8%]), glycated hemoglobin testing (predicted probability, 58.5% [95% CI, 58.2%-58.5%] vs 60.4% [95% CI, 60.3%-60.6%]), or low-density lipoprotein cholesterol testing (predicted probability, 85.2% [95% CI, 85.0%-85.5%] vs 86.0% [95% CI, 85.9%-86.1%]). They were also more likely to experience all-cause 30-day readmissions (predicted probability, 16.4% [95% CI, 16.1%-16.7%] vs 15.7% [95% CI, 15.6%-15.8%]). However, as the level of out-of-network primary care decreased, these gaps closed substantially, such that beneficiaries at ACOs that served many and fewer patients of racial and ethnic minority groups in the lowest percentile of out-of-network primary care received care of comparable quality. This large cohort study found that quality performance among ACOs serving many patients of racial and ethnic minority groups was negatively associated with their level of out-of-network primary care.

Trends in Health Disparities of Rural Latinos Pre- and Post-Accountable Care Organization Implementation.

We present findings from a longitudinal investigation, the purpose of which was to compare health disparities of rural Latino older adult patients diagnosed with diabetes to their non-Latino White counterparts. A pre-post design was implemented treating Medicare Accountable Care Organization (ACO) participation by Rural Health Clinics (RHCs) as an intervention, and using diabetes-related hospitalizations to measure disparities. Data for a nationwide panel of 2,683 RHCs were analyzed for a study period of eight years: 2008 - 2015. In addition, data were analyzed for a subset of 116 RHCs located in Florida, Texas, and California that participated in a Medicare ACO in one or more years of the study period. Two broad findings resulted from this investigation. First, for both the nationwide panel of RHCs and the three-state sample of "ACO RHCs," there was a decrease in the mean disparities in diabetes-related hospitalization rates over the eight-year study period. Second, in comparing a three-year time period after Medicare ACO implementation in 2012 to a four-year period before the implementation, a statistically significant difference in mean disparities was found for the nationwide panel. There are a number of factors that may contribute to the decrease in diabetes-related hospitalization rates for Latinos in more recent years. Future research will identify specific contributors to reducing diabetes-related hospitalization disparities between Latinos and the general population, including the possible influence of ACO participation by RHCs. This paper presents original research conducted using data related to rural Latino older adults. The data represent multiple states and an eight-year time period. The U.S. Latino population is growing at a rapid pace. As a group, they are at a high risk for developing diabetes, the complications of which are serious and costly to the patient and the U.S. healthcare system. With the continued growth of the Latino population, it is critical that their health disparities be monitored, and that factors that contribute to their health and well-being be identified and promoted.

Small practice participation and performance in Medicare accountable care organizations.

Alternative payment models (APMs) encouraging provider collaboration may help small practices overcome the participation challenges that they face in APMs. We aimed to determine whether small practices in accountable care organizations (ACOs) reduced their beneficiaries' spending more than large practices in ACOs. Retrospective cohort study of Medicare patients attributed to ACOs and non-ACOs. We conducted a modified difference-in-differences analysis that allowed us to compare large vs small practices before and after the Medicare Shared Savings Program (MSSP) ACO started, between 2010 and 2016. Our sample included Medicare fee-for-service beneficiaries with 12 months of Medicare Part A and Part B (unless death) who were attributed to small (≤ 15 providers) and large (> 15 providers) practices participating in ACOs and non-ACOs. The outcome was patient annual spending based on CMS' total per capita costs. Patients attributed to small practices in ACOs had annual Medicare spending decreases of $269 (95% CI, $213-$325; P < .001) more than patients attributed to large practices in ACOs. Small ACO practices reduced spending more than large practices by $165 for physician services (95% CI, $140-$190; P < .001), $113 for hospital/acute care (95% CI, $65-162; P < .001), and $52 for other services (95% CI, $27-$77; P < .001). Small practices in ACOs spent $253 more on average at baseline than small practices in non-ACOs. ACOs with a higher proportion of small practices were more likely to receive shared savings payments. Small practices in ACOs controlled costs more so than large practices. Small practice participation may generate higher savings for ACOs.