Chartis: A look at Medicare Advantage enrollment trends in 2024

Medicare Advantage (MA) growth has broadly slowed, but the biggest players in this space continue to claim the lion's share of this expansion, according to a new report from healthcare consultant Chartis.

The analysis found that 1.7 million lives were added to the MA rolls for the 2024 plan year, and, of those, 1.4 million, or 86%, were captured by the three largest insurers in this segment: UnitedHealthcare, Humana and Aetna. Aetna, in particular, had a strong showing during the annual enrollment period, adding 476,000 enrollees, or 60% of those who signed up during that window.

UnitedHealth and Humana also grew during the annual enrollment period, according to the report, but at a rate below that of the period overall and below their own performance in previous enrollment periods. UHC added 119,000 members in the annual enrollment period, but much of that came from employer group waiver plans rather than individual sign-ups, Chartis found. Humana added 112,000 lives during the annual enrollment period.

Centene, meanwhile, shed 215,000 members for 2024, the report found. The analysts did not find this surprising, given that Centene has struggled with its performance in the star ratings program. Elevance Health's MA membership also declined this year, down by 25,000 lives.

"The Medicare Advantage market is at an inflection point. The past few years have seen unprecedented enrollment growth, fueled by a rapidly increasing senior segment and an enabling regulatory environment," the analysts said. "While growth this year remained strong, it was slower than in years past. What’s more, conflicting trends converging on Medicare Advantage organizations may result in more tempered growth going forward."

"Meanwhile, the big keep getting bigger," they added.

These enrollment trends pose a major challenge for Blue Cross Blue Shield plans and other nonprofits looking to expand their reach in MA, according to the report. Just 9% of new enrollment was in Blues plans, and 9% was in nonprofits not associated with the Blues network. The remaining 82% of sign-ups were added to for-profit plans, and the for-profit carriers now account for 73.5% of all MA enrollment.

Blues insurers collectively added 147,000 members in MA, with Health Care Service Corporation and Blue Cross Blue Shield of Michigan gaining the most. Other nonprofit insurers together added 155,000 members, with the largest growth at Kaiser Permanente and HealthFirst.

Startup insurers now account for 2% of enrollment in MA, according to the report, with Devoted Health and Alignment Healthcare charting the largest gains.

Even as large numbers of people age into Medicare, the analysts said they expect overall growth in the program to slow. Enrollment growth in MA likely peaked in 2020, according to the report. Between 2020 and 2025, the Chartis consultants said they expect to see total MA growth of about 16%, compared to 22% between 2015 and 2020.

Growth will likely drop off substantially starting in 2040, according to the report.

"That said, the senior population will continue to grow at a faster rate than other population segments for the foreseeable future," the analysts wrote.