Reimbursement
Forty-three percent of returning consumers to the federal government's online exchange, healthcare.gov, switched policies last year.
Insurer said it is still trying to negotiate a new contract with the major public hospital operator.
Huge final rule already has healthcare pros celebrating or lamenting the release.
Provider network can be an important factor for some consumers, especially given the growing number of plans with no out-of-network benefits.
Program cements two payment tracks and "pick your pace" approach while setting aside money to support small practices.
Federal officials send letters to beneficiaries explaining that they can keep exchange plans but lose subsidies since they are eligible for Medicare.
Industry watchdog is calling on CMS to allow insurers even more flexibility and to expand the pilot program to all states.
Humana saw enrollment in plans rated four stars or higher fall to 37 percent compared to 71 percent in the prior year's ratings, pushing the company's stock down close to 5 percent in morning trading.
The Affordable Care Act provides bonuses to higher quality plans that rate four or five stars on a five-star scale.
Insurer also adds remote access technology, at no copay cost, to all Medicare Advantage plans.