Mortality Gap Between Puerto Rico and the US Mainland Among Medicare Advantage Enrollees

ABSTRACT

Health care and outcomes in Puerto Rico (PR) have been impacted by US federal policies, including those pertaining to the Medicare Advantage (MA) program. The MA enrollment rate in the US mainland is 54%, but in PR, it is more than 90%. In addition to this stark difference in MA enrollment rate, MA plan payments and quality—which may impact mortality of enrollees—also differ between PR and the US. Despite these differences, little is known about the mortality gap between PR and the US among MA enrollees.

We compared mortality rates between Hispanic MA enrollees in PR and Hispanic and White enrollees in the US from 2010 to 2022, adjusting for age and sex in each year. We found that among MA enrollees, the mortality of Hispanic enrollees in PR was significantly higher than that of Hispanic enrollees in the US. The findings may be explained by lower quality of care provided to PR Hispanic enrollees compared with US Hispanic enrollees, particularly within MA plans. Our results provide insights into existing disparities among MA enrollees in PR and the US mainland.

Am J Manag Care. 2025;31(10):In Press

Takeaway Points

• Among Medicare Advantage (MA) enrollees, the mortality of Hispanic enrollees in Puerto Rico (PR) was significantly higher than that of Hispanic enrollees in the US.
• The findings may be explained by lower quality of care provided to PR Hispanic enrollees compared with US Hispanic enrollees, particularly within MA plans.
• Our results provide insights into existing disparities among MA enrollees in PR and the US mainland.

Health care and outcomes in Puerto Rico (PR) have been impacted by US federal policies, including those pertaining to the Medicare Advantage (MA) program. In the US mainland, MA enrollment has been rapidly growing during the past 2 decades, currently accounting for 54% of all Medicare beneficiaries.1 Most MA plans offer lower cost sharing, a maximum out-of-pocket limit, and supplemental benefits, which are highly attractive to low-income individuals.2 Due to the high poverty rate and unfavorable features of traditional Medicare in PR (exclusion of low-income subsidy in Part D and nonautomatic enrollment in Part B), more than 90% of Medicare beneficiaries in PR were enrolled in MA, which is the highest in any US state and/or territory.1In addition to this stark difference in MA enrollment rates, MA plan payments and quality—which may affect mortality of enrollees—also differ between PR and the US.3 Despite these differences, little is known about the mortality gap between PR and the US mainland (including Alaska and Hawaii) among MA enrollees.

METHODS

The primary data source was 100% CMS Master Beneficiary Summary File (MBSF) for Puerto Rico and 20% MBSF for the US mainland. A Medicare beneficiary was identified as an MA enrollee in a given year if the beneficiary was enrolled in an MA plan in any month of the year. We excluded migrants from PR to the US in a given year. The MBSF contains the date of death as well as the beneficiary’s demographic characteristics such as age, sex, and race/ethnicity.

We compared mortality rates between Hispanic MA enrollees in PR and Hispanic and White enrollees in the US from 2010 to 2022, adjusting for age and sex in each year.

RESULTS

The study population included 7,304,164 MA enrollees (792,530 PR Hispanic enrollees, 829,806 US Hispanic enrollees, and 5,681,828 US White enrollees) who were 65 years or older.

The Figure shows that the adjusted mortality gap between PR and US Hispanic enrollees was 0.85 percentage points (PP) (95% CI, 0.75-0.95) in 2010 and narrowed to 0.33 PP (95% CI, 0.26-0.39) in 2022. In contrast, the gap between PR Hispanic and US White enrollees changed from 0.17 PP (95% CI, 0.10-0.24) in 2010 to –0.59 PP (95% CI, –0.64 to –0.53) in 2022. The results were consistent when we defined an MA enrollee as a beneficiary who enrolled in an MA plan throughout a year (not shown).

DISCUSSION

We found that among MA enrollees, the mortality of PR Hispanic enrollees was significantly higher than that of US Hispanic enrollees, with the exceptions of 2020 and 2021, likely due to higher COVID-19 mortality among US Hispanic than PR Hispanic enrollees. In contrast, the mortality of PR Hispanic enrollees was lower than that of US White enrollees. The findings may be explained by lower access and quality of care provided to PR Hispanic enrollees compared with US Hispanic enrollees.4,5 In addition, MA plans in PR receive a significantly lower payment (approximately 40% lower benchmark payment) than those in the US.3 This may result in provider shortages and limited provider networks, access to care, and quality, all of which may lead to higher mortality among PR enrollees compared with US enrollees.6 Further studies are warranted to better understand underlying factors for the narrowed mortality gap among MA enrollees.

Limitations include the lack of information on enrollees’ socioeconomic variables and region-specific factors that may influence the mortality gap we found. We cannot exclude the possibility that differences in unobserved factors may have accounted for our results. Despite these limitations, our results provide insights into existing disparities among MA enrollees in PR and the US mainland.

Author Affiliations: Department of Health Services, Policy and Practice, Brown University (DK, ANT, DJM, MR-H), Providence, RI; Providence VA Medical Center (ANT), Providence, RI.

Source of Funding: National Institute on Aging of the National Institutes of Health (K01AG057822; RF1AG078262).

Author Disclosures: Dr Meyers has received personal fees as a senior adviser to the Center for Medicare and Medicaid Innovation and grants from the National Institute on Aging. Dr Rivera-Hernandez has received grants from the National Institutes of Health, received honoraria from the Oklahoma Dementia Care Network (sponsored by the Health Resources and Services Administration Geriatrics Workforce Enhancement Program and HHS through the Building Our Largest Dementia Infrastructure for Alzheimer’s Act), and attended the Oklahoma Dementia Care Network Annual Innovations in Aging Conference and AcademyHealth and Gerontological Society of America meetings. The remaining authors report no relationship or financial interest with any entity that would pose a conflict of interest with the subject matter of this article.

Authorship Information: Concept and design (DK, ANT, DJM, MR-H); analysis and interpretation of data (DK, ANT, DJM, MR-H); drafting of the manuscript (DK); critical revision of the manuscript for important intellectual content (DK, ANT, DJM, MR-H); statistical analysis (DK); and obtaining funding (MR-H).

Address Correspondence to: Daeho Kim, PhD, Department of Health Services, Policy and Practice, Brown University, 121 S Main St, Providence, RI 02903. Email: Daeho_Kim@brown.edu.

REFERENCES

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