In 15 states, only one insurer dominates with the majority share of the health insurance market, according to a new study from the American Medical Association (AMA).
The AMA used 2011 data to examine state and metropolitan areas, finding 10 states--Alabama, Hawaii, Michigan, Delaware, Alaska, South Carolina, North Dakota, Nebraska, Louisiana and Rhode Island--have the least competitive insurance markets.
It also found 15 states had one insurer with at least 50 percent of the commercial market share, while 45 states had two insurers with a combined market share of at least 50 percent.
"In far too many states, one or two insurance companies dominate the market, which can hurt patients, physicians and employers," AMA President Ardis Dee Hoven said in a statement. "Without rivals to compete against, a large health insurance company can take advantage of patients by raising premiums and dictating important aspects of patient care."
Low competition within the insurance industry could worsen with the health insurance exchanges, according to healthcare economists, as states with very little competition will likely see continued strong marketplace dominance by one or two insurers in the exchanges, FierceHealthPayer previously reported.
Alabama has the least competitive health insurance industry with Blue Cross Blue Shield accounting for 86 percent of the market, though the AMA noted Blue Cross's share decreased slightly from 88 percent the year before.
Despite holding such a dominant portion of Alabama's market, Blue Cross says it offers some of the lowest premiums in the country. "Our customers' faith in us has provided us our market share, and we have to continue to earn that every day," spokeswoman Koko Mackin told the Birmingham News.