Many regions are "stubbornly highly concentrated" when it comes to commercial health coverage, according to a new analysis from the American Medical Association (AMA).
The AMA released its annual look at concentration in commercial insurance markets Tuesday, in which it found that 95% of metropolitan statistical area-level markets were highly concentrated per federal standards in both 2014 and 2023. The study examined 382 MSAs across all 50 states and the District of Columbia.
The number of markets that were highly concentrated has consistently been between 95% and 96% over the past decade, the AMA found. Close to half (49%) of markets that were highly concentrated in 2014 only became more so by 2023.
“For too many Americans living in highly concentrated health insurance markets, choosing medical coverage feels like having no choice at all,” said AMA President Bruce A. Scott, M.D., in an announcement. “The AMA strongly encourages a dialogue among regulators, policymakers, lawmakers, and others to reverse the trend toward health insurance consolidation and create a better, more open and competitive marketplace to benefit patients.”
The study found that in 89% of markets, a single payer held a commercial market share of at least 30%. In 47% of regions, a single insurer owned at least 50% of the market.
A Blue Cross Blue Shield plan held the largest share in 83% of the MSAs included in the study, the AMA found. At the state-level, BCBS insurers also held the largest share of the market in 41 states.
Elevance Health's plans held the largest market share in 21% of MSAs, according to the study. UnitedHealth Group, meanwhile, was the largest payer nationally by market share, with Centene holding the largest share on the Affordable Care Act's exchanges.
The study also outlined the 10 states with the most concentrated insurance markets: Alabama, Kentucky, Michigan, Louisiana, Hawaii, Illinois, Alaska, Delaware, Vermont and South Carolina.
Beyond the commercial market, the study also found that Medicare Advantage (MA) is highly concentrated. In 2023, 97% of MSA-level MA markets were highly concentrated. This figure has largely been between 97% and 99% since 2017, according to the report.
UnitedHealth also controls the largest market share nationally in MA at 29%, an increase from its 25% market share in 2017. The insurer held the largest share in 43% of MSA-level markets, the study found.