UCLA Center for Health Policy Research

Lower Cost, Wider Coverage? Potential Effects of Medicare Advantage Enrollment on the Health Care Costs of Older Californians

Mohammad Khorgamphar, Sithara Diunugala, D. Imelda Padilla-Frausto, PhD, MPH, Kathryn G. Kietzman, PhD, MSW

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Fact Sheet Press Release Infographic

Highlights

In Amador County, a 20% or higher Medicare Advantage enrollment rate was associated with lower health care costs over a 10-year period.

Four other counties — Kings, Santa Cruz, Tulare, and Yuba — also had high MA enrollment rates and lower monthly health care costs from one year to the next.

Housing costs were the biggest proportion of household budgets, particularly among single homeowners with a mortgage who lived alone.

Summary

Published Date: August 28, 2025

This fact sheet explores the relationship between Medicare Advantage (MA) enrollment rates — that is, the proportion of Medicare beneficiaries enrolled in MA plans — and health care costs as estimated by the California Elder Index™. Authors also examine how the overall cost of living for single older adults (including health care, housing, food, transportation, and miscellaneous expenses) changed between 2013 and 2023.

Findings: When health care costs at the county level, the MA enrollment rate is 20% or higher. However, this decrease does not extend to the overall cost of living for single older adults living alone, with that figure remaining elevated due to the increasing prices of housing, food, and other nonhealth care costs.

Data Points

3 x as high

Estimated monthly housing costs in 2023 for single older adults with a mortgage living alone in Amador County ($1,048) compared with single renters ($498).

$557 vs. $273

Estimated monthly cost of health care in 2023 for single older Californians living alone in counties with Medicare Advantage enrollment under 20% vs. in counties with enrollment over 20%.

54% vs. 11%

Increase in estimated monthly cost of health care for single older Californians living alone in counties with MA enrollment under 20% vs. in counties with MA enrollment over 20% from 2013 to 2023.