Medicare-Covered Services Near the End of Life in Medicare Advantage vs Traditional Medicare.

Importance: Financial incentives in Medicare Advantage (MA), the managed care alternative to traditional Medicare (TM), were designed to reduce overutilization. For patients near the end of life (EOL), MA incentives may reduce potentially burdensome care and encourage hospice but could also restrict access to costly but necessary services. Objective: To compare receipt of potentially burdensome treatments and transfers and potentially necessary postacute services in the last 6 months of life in individuals with MA vs TM. Design, Setting, and Participants: A retrospective analysis of Medicare claims data among older Medicare beneficiaries who died between 2016 and 2018. The study included Medicare decedents aged 66 years or older covered by TM (n = 659 135) or MA (n = 360 430). All decedents and the subset of decedents with 1 or more emergent hospitalizations with a life-limiting condition (cancer, dementia, end-stage organ failure) that would likely qualify for hospice care were included. Exposure: MA enrollment. Main Outcomes: Receipt of potentially burdensome hospitalizations and treatments; receipt of postdischarge home and facility care. Results: The study included 659 135 TM enrollees (mean [SD] age at death, 83.3 [9.0] years, 54% female, 15.1% non-White, 55% with 1 or more life-limiting condition) and 360 430 MA enrollees (mean [SD] age at death 82.5 [8.7] years, 53% female, 19.3% non-White, 49% with 1 or more life-limiting condition). After regression adjustment, MA enrollees were less likely to receive potentially burdensome treatments (-1.6 percentage points (pp); 95% CI, -2.1 to -1.1) and less likely to die in a hospital (-3.3 pp; 95% CI, -4.0 to -2.7) compared with TM. However, when hospitalized, MA enrollees were more likely to die in the hospital (adjusted difference, 1.3 pp; 95% CI, 1.1-1.5) and less likely to be transferred to rehabilitative or skilled nursing facilities (-5.2 pp; 95% CI, -5.7 to -4.6). Higher rates of home health and home hospice among those discharged home offset half of the decline in facility use. Results were unchanged in the life-limiting conditions sample. Conclusions: MA enrollment was associated with lower rates of potentially burdensome and facility-based care near the EOL. Greater use of home-based care may improve quality of care but may also leave patients without adequate assistance after hospitalization.

Racial and Ethnic Disparities in Geographic Availability of Buprenorphine.

OBJECTIVES: Overdose mortality has risen most rapidly among racial and ethnic minority groups while buprenorphine prescribing has increased disproportionately in predominantly non-Hispanic White urban areas. To identify whether buprenorphine availability equitably meets the needs of diverse populations, we examined the differential geographic availability of buprenorphine in areas with greater concentrations of racial and ethnic minority groups. METHODS: Using IQVIA longitudinal prescription data, IQVIA OneKey data, and Microsoft Bing Maps, we calculated 2 outcome measures across the continental United States: the number of buprenorphine prescribers per 1000 residents within a 30-minute drive of a ZIP code, and the number of buprenorphine prescriptions dispensed per capita at retail pharmacies among nearby buprenorphine prescribers. We then estimated differences in these outcomes by ZIP codes' racial and ethnic minority composition and rurality with t tests. RESULTS: Buprenorphine prescribers per 1000 residents within a 30-minute drive decreased by 3.8 prescribers per 1000 residents in urban ZIP codes (95% confidence interval = -4.9 to -2.7) and 2.6 in rural ZIP codes (95% confidence interval = -3.0 to -2.2) whose populations consisted of ≥5% racial and ethnic minority groups. There were 45% to 55% fewer prescribers in urban areas and 62% to 79% fewer prescribers in rural areas as minority composition increased. Differences in dispensed buprenorphine per capita were similar but larger in magnitude. CONCLUSIONS: Achieving more equitable buprenorphine access requires not only increasing the number of buprenorphine-prescribing clinicians; in urban areas with higher racial and ethnic minority group populations, it also requires efforts to promote greater buprenorphine prescribing among already prescribing clinicians.

Traditional Medicare supplemental insurance and the rise of Medicare Advantage.

OBJECTIVES: Most Medicare beneficiaries obtain supplemental insurance or enroll in Medicare Advantage (MA) to protect against potentially high cost sharing in traditional Medicare (TM). We examined changes in Medicare supplemental insurance coverage in the context of MA growth. STUDY DESIGN: Repeated cross-sectional analysis of the Medicare Current Beneficiary Survey from 2005 to 2019. METHODS: We determined whether Medicare beneficiaries 65 years and older were enrolled in MA (without Medicaid), TM without supplemental coverage, TM with employer-sponsored supplemental coverage, TM with Medigap, or Medicaid (in TM or MA). RESULTS: From 2005 to 2019, beneficiaries with TM and supplemental insurance provided by their former (or current) employer declined by approximately half (31.8% to 15.5%) while the share in MA (without Medicaid) more than doubled (13.4% to 35.1%). The decline in supplemental employer-sponsored insurance use was greater for White and for higher-income beneficiaries. Over the same period, beneficiaries in TM without supplemental coverage declined by more than a quarter (13.9% to 10.1%). This decline was largest for Black, Hispanic, and lower-income beneficiaries. CONCLUSIONS: The rapid rise in MA enrollment from 2005 to 2019 was accompanied by substantial changes in supplemental insurance with TM. Our results emphasize the interconnectedness of different insurance choices made by Medicare beneficiaries.

Medicare Advantage plan characteristics associated with sorting their beneficiaries to providers that generate fewer avoidable hospital stays.

OBJECTIVE: To examine whether certain Medicare Advantage (MA) plan characteristics are associated with driving beneficiaries to providers that generate fewer avoidable hospital stays. DATA SOURCES: This paper primarily used 2018-2019 MA encounter data and traditional Medicare (TM) claims data for a nationally representative 20% sample of Medicare beneficiaries. STUDY DESIGN: For each plan design aspect-plan type, carrier, star rating, and network breadth-we estimated two adjusted Poisson regressions of avoidable hospital stays: one without clinician fixed effects and the other with. We calculated the difference between the coefficients to evaluate the extent to which patient sorting affected avoidable hospital stays relative to TM. DATA EXTRACTION METHODS: Our sample included Medicare beneficiaries 65 years and older who were continuously enrolled in either MA or TM during 2018-2019. Beneficiaries in our sample had one or more chronic, ambulatory care-sensitive conditions. PRINCIPAL FINDINGS: Patient sorting can be attributed to certain characteristics of plan design aspects. For plan type, HMOs account for 86%, with PPOs accounting for only 14%. For carriers, Humana and smaller carriers account for 89%. For star ratings, high-star contracts account for 94%, with other stars only accounting for 6%. By network design, narrow network plan-counties explained 20% of the patient sorting effect. CONCLUSIONS: While MA plans were found to be associated with driving beneficiaries to providers that generate fewer avoidable hospital stays, the effect is not homogeneous across the characteristics of MA plans. HMOs and high-star contracts are drivers of this MA phenomenon.

Composition of buprenorphine prescribing networks in Medicaid and association with quality of care.

INTRODUCTION: Despite Medicaid's outsized role in delivering and financing medications for opioid use disorder (MOUD), little is known about the extent to which buprenorphine prescriber networks vary across Medicaid health plans, and whether network characteristics affect quality of treatment received. In this observational cross-sectional study, we used 2018-2019 Medicaid claims in Oregon to assess network variation in the numbers and types of buprenorphine prescribers, as well as the association of prescriber and network characteristics with quality of care. METHODS: We describe prescribers (MD/DOs and advanced practice providers) of OUD-approved buprenorphine formulations to patients with an OUD diagnosis, across networks. For each patient who initiated buprenorphine treatment during 2018, we assigned a "usual prescriber" and assessed four measures of quality in the 180d following initiation: 1) continuous receipt of buprenorphine; 2) receipt of any behavioral health counseling services; 3) receipt of any urine drug screen; and 4) receipt of any prescription for a benzodiazepine. We used multivariable linear regressions to examine the association of prescriber and network characteristics with quality of buprenorphine care following initiation. RESULTS: We identified 645 providers who prescribed buprenorphine to 20,739 eligible Medicaid enrollees with an OUD diagnosis. The composition of buprenorphine prescriber networks varied in terms of licensing type, specialty, and panel size, with the majority of prescribers providing buprenorphine to small panels of patients. In the 180 days following initiation, a third of patients were maintained on buprenorphine; 69.9 % received behavioral health counseling; 88.4 % had a urine drug screen; and 11.3 % received a benzodiazepine prescription. In regression analyses, while no single network characteristic was associated with higher quality across all examined measures, each one unit increase in prescriber-to-enrollee ratio was associated with a 1.18 p.p. increase in the probability of continuous buprenorphine maintenance during the 180 days following initiation (95 % confidence interval = [0.21, 2.15], p = 0.017). CONCLUSIONS: Medicaid plans may be able to leverage their networks to provide higher quality care. Our findings, which should be interpreted as descriptive only, suggest that higher prescriber-to-enrollee ratio is associated with increased buprenorphine maintenance. Future research should focus on isolating the causal relationships between MOUD prescribing network design and patient outcomes.

Commercial Insurer Market Power and Medicaid Managed Care Networks.

Over 70% of Medicaid beneficiaries are enrolled in Medicaid managed care (MMC). MMC provider networks therefore represent a critical determinant of access to the Medicaid program. Many MMC insurers also participate in commercial insurance markets where prices are high, and some insurers exercise considerable market power. In this paper, we examined the relationship between commercial insurer market power and MMC physician network breadth using linked national enrollment data and provider directory data. Insurers with more commercial market power had broader Medicaid physician networks. Insurers with over 30% market share had 37.3% broader Medicaid networks than insurers in the same county that had no commercial market share. These differences were driven by greater breadth among primary care providers, as well as other specialists including OB/GYNs, surgeons, neurologists, and cardiologists. Commercial insurance market power may have spillovers on access to care for MMC beneficiaries.

Increases in Medicare Spending and Use after Private Equity Acquisition of Retina Practices.

PURPOSE: Private equity (PE) firms increasingly are acquiring physician practices in the United States, particularly within procedural-based specialties such as ophthalmology including retina. To date, the potential impact of ophthalmology practice acquisitions remains unknown. We evaluated the association between PE acquisition and Medicare spending and use for common retina services. DESIGN: Retrospective difference-in-differences analysis using the 20% Medicare fee-for-service claims dataset from January 1, 2015, through December 31, 2019. PARTICIPANTS: Eighty-two practices acquired by PE during the study period and matched control practices. METHODS: We used novel data on PE acquisitions of retina practices linked to the 20% sample Medicare claims data. Retina practices acquired by PE between 2016 and 2019 were matched to up to 3 non-PE (control) practices based on characteristics before acquisition. Private equity-acquired practices were compared with matched control practices through 6 quarters after acquisition using a difference-in-differences event study design. Data analyses were performed between August 2022 and April 2023. MAIN OUTCOME MEASURES: Medicare spending and use of common retina services. RESULTS: Relative to control practices, PE-acquired retina practices increased the use of higher-priced anti-vascular endothelial growth factor (VEGF) agents including aflibercept, which differentially increased by 6.5 injections (95% confidence interval, 0.4-12.5; P = 0.03) per practice-quarter, or 22% from baseline. As a result, Medicare spending on aflibercept differentially increased by $13 028 per practice-quarter, or 21%. No statistically significant differences were found in use or spending for evaluation and management visits or diagnostic imaging. CONCLUSIONS: Private equity acquisition of retina practices are associated with modest increases in the use of higher-priced anti-VEGF drugs like aflibercept, leading to higher Medicare spending. This finding highlights the need to monitor the influence of PE firms' financial incentives over clinician decision-making and the appropriateness of care, which could be swayed by strong economic incentives. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Role of Patient Sorting in Avoidable Hospital Stays in Medicare Advantage vs Traditional Medicare.

Importance: Unlike traditional Medicare (TM), Medicare Advantage (MA) plans limit in-network care to a specific network of Medicare clinicians. MA plans thus play a role in sorting patients to a subset of clinicians. It is unknown whether the performance of physicians who treat MA and TM beneficiaries is different. Objective: To examine whether avoidable hospital stay differences between MA and TM can be explained by the primary care clinicians who treat MA and TM beneficiaries. Design, Setting, and Participants: This was a cross-sectional study of a nationally representative sample of MA and TM beneficiaries in 2019 with any of 5 chronic ambulatory care-sensitive conditions (ACSCs). The relative risk (RR) of avoidable hospital stays in MA compared with TM was estimated with inverse probability of treatment-weighted Poisson regression, both without and with clinician fixed effects. The degree to which the estimated MA vs TM difference could be explained by patient sorting was calculated by comparing the 2 RR estimates. Data were analyzed between February 2022 and April 2023. Exposure: Enrollment in MA. Main Outcome and Measures: Whether a beneficiary had avoidable hospital stays in 2019 due to any of the ACSCs. Avoidable hospital stays included both hospitalizations and observation stays. Results: The study sample comprised 1 323 481 MA beneficiaries (mean [SD] age, 75.4 [7.0] years; 56.9% women; 69.3% White) and 1 965 863 TM beneficiaries (mean [SD] age, 75.9 [7.4] years; 57.1% women; 82.5% White). When controlling for the primary care clinician, the RR of avoidable hospital stays in MA vs TM changed by 2.6 percentage points (95% CI, 1.72-3.50; P < .001), suggesting that compared with TM beneficiaries, MA beneficiaries saw clinicians with lower rates of avoidable hospital stays. This effect size was statistically significant to explain the 2% lower rate of avoidable hospital stays in MA than in TM. Conclusions and Relevance: In this cross-sectional study of MA and TM beneficiaries, the lower rate of avoidable hospital stays among MA beneficiaries than TM beneficiaries was attributable to MA beneficiaries visiting clinicians with lower rates of avoidable hospital stays. The patient sorting that occurs in MA plays a critical role in the lower rates of avoidable hospital stays compared with TM.

Trends in Medicare Advantage participation among commercial insurers.

OBJECTIVES: Commercial health insurers can participate in the rapidly growing Medicare Advantage (MA) market, which may affect network formation and prices in traditional commercial insurance markets. We aim to quantify the prevalence and growth of commercial insurers participating in MA within the same state. STUDY DESIGN: Repeated cross-sectional analysis of Clarivate's Interstudy enrollment data comprising the universe of insurers in the United States from 2015 to 2021. METHODS: We calculated the share of employer-sponsored insurance (ESI) enrollees covered by an insurer offering MA in their state in 2015, 2017, 2019, and 2021. We documented this share across states, years, and the state's 2015 tercile. RESULTS: Between 2015 and 2021, the share of ESI enrollees covered by an insurer offering MA in the same state increased from 83.5% to 95.3%. This growth was concentrated in states with initially low rates in 2015 (lowest 2015 state tercile, ≤ 70.5%), in which the share grew from 47.6% to 87.9%. In 2015, 23.5% of states had a share greater than 90.0% compared with 74.5% in 2021. CONCLUSIONS: By 2021, almost all ESI enrollees were covered by insurers who participated in MA in the same state. Future research should investigate how insurer participation in MA affects network formation and prices in commercial markets.

New Opportunities to Strengthen Medicaid Managed Care Network Adequacy Standards.

This Viewpoint discusses new standards proposed by the Centers for Medicare & Medicaid Services for ensuring that Medicare managed care networks meet enrollees' needs.

Association of Medicare Program Type with Health Care Access, Utilization, and Affordability among Cancer Survivors.

BACKGROUND: The Medicare Advantage program provides care to nearly half of Medicare beneficiaries, including a rapidly growing population of cancer survivors. Despite its increased adoption, it is still unknown whether or not the program improves healthcare access, outcomes, and affordability for cancer survivors. METHODS: We performed a cross-sectional study of Medicare beneficiaries aged ≥ 65 years with a self-reported history of cancer from the 2019 National Health Interview Survey. We used multivariable logistic regression to evaluate the association between Medicare program type (Medicare Advantage vs. traditional Medicare) and measures of healthcare access, acute care utilization, and affordability. RESULTS: We identified 4451 beneficiaries with a history of cancer, corresponding to 26.6 million weighted cancer survivors in 2019. Of the beneficiaries, 35.8% were enrolled in Medicare Advantage, whereas 64.2% were enrolled in traditional Medicare. The age, sex, racial and ethnic composition, household income, primary site of cancer, and comorbidity burden of Medicare Advantage and traditional Medicare beneficiaries were similar. In the adjusted analysis, there were no differences in healthcare access or acute care utilization between traditional Medicare and Medicare Advantage beneficiaries. However, cancer survivors enrolled in Medicare Advantage were more likely to worry about (34.3% vs. 29.4%; aOR, 1.3 (95% CI, 1.1-1.5)) or have problems paying (13.6% vs. 11.1%; aOR, 1.4 (95% CI, 1.1-1.8)) medical bills. CONCLUSIONS: We found no evidence that Medicare Advantage beneficiaries with cancer had better healthcare access, affordability, or acute care utilization than traditional Medicare beneficiaries did. Furthermore, Medicare Advantage beneficiaries were more likely to report financial strain and have difficulty paying for their medical bills than were those with traditional Medicare. Despite the generous benefits and attractive incentives, Medicare Advantage plans may not be more cost-effective than traditional Medicare is for cancer survivors. Our study informs ongoing congressional deliberations to re-evaluate the role of Medicare Advantage in promoting equity among beneficiaries with cancer.

Psychiatrist Networks In Medicare Advantage Plans Are Substantially Narrower Than In Medicaid And ACA Markets.

Medicare Advantage now covers twenty-eight million older adults, many of whom have mental health needs. Enrollees are often restricted to providers who participate in a health plan's network, which may present a barrier to care. We used a novel data set linking network service areas, plans, and providers to compare psychiatrist network breadth-the percentage of providers in a given area that are considered "in network" for a plan-across Medicare Advantage, Medicaid managed care, and Affordable Care Act plan markets. We found that nearly two-thirds of psychiatrist networks in Medicare Advantage were narrow (that is, they contained fewer than 25 percent of providers in a network's service area) compared with approximately 40 percent in Medicaid managed care and Affordable Care Act plan markets. We did not observe similar differences in network breadth for primary care physicians or other physician specialists across markets. Amid efforts to strengthen network adequacy, our findings suggest that psychiatrist networks in Medicare Advantage are particularly narrow, which may disadvantage enrollees as they attempt to obtain mental health services.

Using remotely monitored patient activity patterns after hospital discharge to predict 30 day hospital readmission: a randomized trial.

Hospital readmission prediction models often perform poorly, but most only use information collected until the time of hospital discharge. In this clinical trial, we randomly assigned 500 patients discharged from hospital to home to use either a smartphone or wearable device to collect and transmit remote patient monitoring (RPM) data on activity patterns after hospital discharge. Analyses were conducted at the patient-day level using discrete-time survival analysis. Each arm was split into training and testing folds. The training set used fivefold cross-validation and then final model results are from predictions on the test set. A standard model comprised data collected up to the time of discharge including demographics, comorbidities, hospital length of stay, and vitals prior to discharge. An enhanced model consisted of the standard model plus RPM data. Traditional parametric regression models (logit and lasso) were compared to nonparametric machine learning approaches (random forest, gradient boosting, and ensemble). The main outcome was hospital readmission or death within 30 days of discharge. Prediction of 30-day hospital readmission significantly improved when including remotely-monitored patient data on activity patterns after hospital discharge and using nonparametric machine learning approaches. Wearables slightly outperformed smartphones but both had good prediction of 30-day hospital-readmission.

State Policy and the Breadth of Buprenorphine-Prescriber Networks in Medicaid Managed Care.

Provider networks in Medicaid Managed Care (MMC) play a crucial role in ensuring access to buprenorphine, a highly effective treatment for opioid use disorder. Using a difference-in-differences approach that compares network breadth across provider specialties and market segments within the same state, we investigated the association between three Medicaid policies and the breadth of MMC networks for buprenorphine prescribers: Medicaid expansion, substance use disorder (SUD) network adequacy criteria, and SUD carveouts. We found that both Medicaid expansion and SUD network adequacy criteria were associated with substantially increased breadth in buprenorphine-prescriber networks in MMC. In both cases, we found that the associations were largely driven by increases in the network breadth of primary care physician prescribers. Our findings suggest that Medicaid expansion and SUD network adequacy criteria may be effective strategies at states' disposal to improve access to buprenorphine.

Medicare advantage and dialysis facility choice.

OBJECTIVE: To compare the characteristics of dialysis facilities used by traditional Medicare (TM) and Medicare advantage (MA) enrollees with end-stage kidney disease (ESKD). DATA SOURCES: We used 20% TM claims and 100% MA encounter data from 2018 and publicly available data from the Centers for Medicare and Medicaid Services. STUDY DESIGN: We compared the characteristics of the dialysis facilities treating TM and MA patients in the same ZIP code, adjusting for patient characteristics. The outcome variables were facility ownership, distance to the facility, and several measures of facility quality. DATA COLLECTION/EXTRACTION: We identified point prevalent dialysis patients as of July 15, 2018. PRINCIPAL FINDINGS: Compared to TM patients in the same ZIP code, MA patients were 1.84 percentage points more likely to be treated at facilities owned by the largest two dialysis organizations and 1.85 percentage points less likely to be treated at an independently owned facility. MA patients went to further and lower quality facilities than TM patients in the same ZIP code. However, these differences in facility quality were modest. For example, while the mean dialysis facility mortality rate was 21.85, the difference in mortality rates at facilities treating MA and TM patients in the same ZIP code was 0.67 deaths per 100 patient-years. Similarly, MA patients went to facilities that were, on average, 0.15 miles further than TM patients in the same ZIP code. CONCLUSION: MA enrollees with ESKD were more likely than TM enrollees in the same ZIP code to use the dialysis facilities owned by the two largest chains, travel further for care, and receive care at lower quality facilities. While the magnitude of differences in facility distance and quality was modest, the direction of these results underscores the importance of monitoring dialysis network adequacy as ESKD MA enrollment continues to grow.

Physician patient sharing relationships within insurance plan networks.

OBJECTIVE: To quantify shared patient relationships between primary care physicians (PCPs) and cardiologists and oncologists and the degree to which those relationships were captured within insurance networks. DATA SOURCES: Secondary analysis of Vericred data on physician networks, CareSet data on physicians' shared Medicare patients, and insurance plan attributes from Health Insurance Compare. Data validation exercises used data from Physician Compare and IQVIA. STUDY DESIGN: Cross-sectional study of the PCP-to-specialist in-network shared patient percentage (primary outcome). We also categorized networks by insurance market segment (Medicare Advantage [MA], Medicaid managed care, small-group or individually purchased), insurance plan type, and network breadth. DATA EXTRACTION: We analyzed data on 219,982 PCPs, 29,400 cardiologists, and 22,745 oncologists who, in 2021, accepted MA (n = 941 networks), Medicaid managed care (n = 293), and individually-purchased (n = 332) and small-group (n = 501) plans. PRINCIPAL FINDINGS: Networks captured, on average, 64.6% of PCP-cardiology shared patient ties, and 61.8% of PCP-oncologist ties. Less than half of in-network ties (44.5% and 38.9%, respectively) were among physicians with a common organizational affiliation. After adjustment for network breadth, we found no evidence of differences in the shared patient percentage across insurance market segments or networks of different types (p-value >0.05 for all comparisons). An exception was among national versus local and regional networks, where we found that national plans captured fewer shared patient ties, particularly among the narrowest networks (58.4% for national networksvs. 64.7% for local and regional networks for PCP-cardiology). CONCLUSIONS: Given recent trends toward narrower networks, our findings underscore the importance of incorporating additional and nuanced measures of network composition to aid plan selection (for patients) and to guide regulatory oversight.

Comparing Medicare Advantage and Traditional Medicare Prices for Hospital Outpatient Services With Hospital Price Transparency Data.

As Medicare Advantage (MA) plans enroll an increasingly large share of Medicare beneficiaries, how much providers charge MA plans relative to Traditional Medicare (TM) has important policy implications. We used new price transparency data from hospitals-which contain the most up-to-date negotiated prices-to evaluate whether and how MA prices differed from TM for hospital outpatient services. We found that among the 1,135 hospitals in our sample, MA prices were close to TM at about half of them, but the other half reported MA prices that deviated considerably from TM, predominantly in the direction of higher rather than lower, and rural hospitals were more likely than urban ones to charge high MA markups. Our findings also suggest that hospital price transparency data hold promise for promoting price shopping among MA beneficiaries. But greater hospital compliance and more standardized reporting are necessary for the data to be a more useful tool.

Psychiatrist and Nonpsychiatrist Physician Network Breadth in Dual Eligible Special Needs Plans.

OBJECTIVE: Dual Eligible Special Needs Plans (D-SNPs) are a type of Medicare Advantage (MA) plan for individuals who have both Medicare and Medicaid coverage. The authors compared the breadths of psychiatrist and nonpsychiatrist provider networks in D-SNPs and other MA plans. METHODS: MA plan provider network data were merged with plan service areas and a nationwide provider database to form a data set with 843 observations on networks subclassified by state and network type (D-SNP or other MA) covering 42 U.S. states and Washington, D.C. Network breadth measured the in-network fraction of clinically active Medicare-accepting psychiatrists and other physician providers in the plans' service areas in each state. Regression analyses were used to compare psychiatrist and nonpsychiatrist network breadth and psychiatrist-nonpsychiatrist breadth differences between D-SNPs and other MA plans, after adjustment for state-level differences. RESULTS: Mean psychiatrist network breadth was 0.319 in D-SNPs and 0.299 in other MA plans, and nonpsychiatrist network breadth was 0.346 in D-SNPs and 0.358 in other MA plans. Psychiatrist networks were narrower than nonpsychiatrist networks (0.303 vs. 0.355, p<0.001), but mean psychiatrist network breadth did not differ between D-SNPs and other MA plans. In regression analyses, the psychiatrist-nonpsychiatrist breadth difference was smaller in D-SNPs (-0.031) than in other MA plans (-0.060) (p=0.002). CONCLUSIONS: Psychiatrist provider networks in a nationwide sample of D-SNPs had similar breadth as psychiatrist networks used in other MA plans. Special provider network adequacy requirements for psychiatrists in D-SNP networks may be worthy of further consideration given D-SNPs' disproportionate enrollment of adults with serious mental illness who have dual Medicare-Medicaid insurance coverage.

Workforce Composition In Private Equity-Acquired Versus Non-Private Equity-Acquired Physician Practices.

Despite growth in private equity (PE) acquisitions of physician practices in the US, little is known about how changes in ownership influence workforce composition. Using clinician-level data linked to practice acquisition information, we estimated changes in clinician workforce composition in PE-acquired practice sites relative to non-PE-acquired independent practice sites for dermatology, ophthalmology, and gastroenterology specialties. We calculated a clinician replacement ratio (cumulative number of entering clinicians during 2014-19 divided by the cumulative number of exiting clinicians) across 213 PE-acquired practices and 995 matched non-PE-acquired practices. Using a difference-in-differences approach, we also examined practice-level changes in yearly clinician counts at PE-acquired practices before and after acquisition compared with non-PE-acquired controls. In aggregate and across the study period, the clinician replacement ratio was higher for PE-acquired practices compared with non-PE-acquired controls (1.75 versus 1.37), as well as within each specialty and clinician type (physician versus advanced practice provider). Relative to non-PE-acquired control practices, we also found significant yearly increases in the number of advanced practice providers at PE-acquired practices after acquisition. Taken together, these findings suggest differential changes in workforce composition at PE-acquired practices, especially a shift toward advanced practice providers for care delivery.