This project looks at the locations of Medicare Shared Savings Program Accountable Care Organizations (ACOs) in the U.S. The ACO model, which started in 2011, is a relatively new health care model. There is a need for more information on the national picture, including demographic details on the ACOs, where they are, who they are serving and who they are not serving. These maps offer a preliminary analysis of Medicare ACO locations at the national level and where these locations are in relation to selected health care vulnerability indicators, mapped at a county level.

Background and maps

In February 2016, CMS listed 433 Medicare ACOs, and at the end of January 2016, Leavitt Partners estimated 838 active ACOs of all kinds (David Muhlestein and Mark McClellan, Accountable Care Organizations In 2016: Private And Public-Sector Growth And Dispersion, April 21, 2016).

Each ACO brings provider participants together to work with each other as a care team. There is a wide variation in the size of the Medicare ACOs, each Medicare ACO is comprised of one or more providers, ranging up to the largest Medicare ACO with 328 providers. The total number of Medicare providers in February 2016 was 14,817 with an average Medicare ACO size coordinating care across a network of 34 providers. Due to data limitations, national Medicare data is used here, the locations do not include state Medicaid, private insurers, Accelerated Development Learning Sessions (ADLS), or other ACO location data.

The maps assess differences in locations across years 2014, 2015 and 2016 (map 5), the relation of locations to urban areas (maps 3), and to hospital referral regions (map 2) below. The rate of Medicare ACOs by county land area is shown on map 4 : the number of ACOs in each county divided into the county land area (square meters). Map 6 displays Medicare ACOs by the number of providers which make up each organization.

The health care indicator maps use the U.S. Census 2014 ACS 5 year data and show rates per county for poverty, high school graduation, disability, 65 years and older, Black or African American alone, and Hispanic or Latino (of any race) (maps 7 – 12), all indicators which have been shown to affect health care outcomes. These investigations led me to focus on the intersection of mid and high rates of poverty (over 18.2%) per county on the mainland U.S.A. and Medicare ACO locations. Map 1 analyses poverty rates by county, using spatial analysis in Cartodb and QGIS.

Results

The 433 Medicare ACOs are spread across 234 counties. Therefore, 2,908 counties have no Medicare ACO (see explanation for 3,142 county total below). This equates as:

• 7.45% of counties have a Medicare ACO
• 92.55% of counties do not have a Medicare ACO

The urban area / urban cluster maps spatially joined the Tiger Urban Area dataset and Medicare ACO locations using QGIS: 87% of Medicare ACOs are within urban areas or urban clusters (map 3).

The 2014 ACS 5 year community survey, 'HC03_EST_VC01, percent below poverty level; estimate; population for whom poverty status is determined' has 3,142 entries for counties (it omits State FIPS 60: American Samoa, 66: Guam, 69: Northern Mariana Islands, 72: Puerto Rico, and 78: Virgin Islands of the U.S.). No Medicare ACOs operate in these 5 states, therefore the analysis was undertaken on the 3,142 county dataset only and the 5 states were exempted. The county poverty rates (percent of population below the poverty level) were divided by equal intervals into three groups: low, mid and high levels:

• 1% - 18.2% low
• 18.2% - 35.4% mid
• 35.4% - 52.6% high
• 1,138 counties (36.22%) out of 3,142 have poverty rates greater than 18.2%

A twenty-mile buffer was created around Medicare ACO locations as an estimated distance for patients to travel for health care. Mid and high-poverty rates (poverty level over 18.2% per county) were selected. This dataset was spatially joined to the buffer table in order to map intersections of poverty and ACOs. Findings showed that:

• 199 (17.49%) mid and high poverty level counties (poverty 18.2% - 52.6%), out of a total of 1,138 have a Medicare ACOs within 20 miles.
• 939 (82.51%) mid and high poverty counties (poverty 18.2% - 52.6%) do not have a Medicare ACO within 20 miles.

Of the 939 counties without a Medicare ACO within 20 miles:

• 43 (4.58%) are high poverty counties (poverty 35.4% - 52.6%).
• 896 (95.42%) are mid poverty counties (poverty 18.2% - 35.4%).

Map 1 details the locations of the 433 Medicare ACOs. A clip of the mid and high level poverty counties which are over 20 miles from a Medicare ACO location show where higher levels of need by county are without resources of a Medicare Accountable Care Organization. The selectors on the right hand side enable choice of Medicare ACOs by size, by ACO track (1, 2, or 3), or by ACO agreement type (initial and renewal). Details on each organization can be found by clicking on the map's ACO locations; zoom is set to 18 for local area details.

Medicare ACO Data

The Medicare Accountable Care Organization (ACO) data is from The Centers for Medicare and Medicaid Services (CMS), part of the Department of Health and Human Services: 2016 Medicare ACO data which lists 433 ACOs in the United States as of February 2016:

CMS notes that "The Medicare Shared Savings Program (or Shared Savings Program) facilitates coordination among providers to improve the quality of care for Medicare fee-for-service beneficiaries while reducing the growth in health care costs. Eligible providers, hospitals, and suppliers may apply to participate in the Shared Savings Program by creating or participating in an Accountable Care Organization (ACO)."