As many as 1,300 Coos County residents enrolled in a Medicare Advantage organization will need to find a new insurance carrier starting Jan. 1.

A change could cost them from $17 to nearly $200 more per month for the private insurance that expands on traditional Medicare coverage.

Mid Rogue Health Plan of Grants Pass has opted to stop offering CareSource Advantage plans in Coos County, a spokesman said. The company blames rising health care costs as part of the reason for the decision. With health care costs going up by 7 to 10 percent a year nationwide, the 3 percent reimbursement rates offered to Advantage programs by Medicare weren’t enough, said Freddy Sennhauser, director of Marketing for Mid Rogue.

The company will continue to offer plans in Curry, Josephine and Jackson counties, but the cost of doing business in Coos County was too high, he said.

“In Coos County, we are losing money,” he said. “It would not be right for our members in Josephine and Jackson counties to pay for the care in Coos County.”

Doctors of the Oregon Coast South serves about 1,100 of CareSource’s low income clients on Medicare and the Oregon Health Plan, said Bill Murray, DOC’s chief executive officer. Not all are seniors. Some are younger, some are pregnant mothers and others are children.

“These people will not have any interruption in their ... coverage,” Murray said.

People on Medicare won’t lose coverage either, but some might revert back to traditional Medicare coverage.

CareSource’s departure is particularly noteworthy, because it offered some of the least expensive plans, according to Cynthia Hylton, a Medicare advocate with Senior Health Insurance Benefits Assistance.

It served 68 percent of Coos County seniors enrolled in an Advantage organization, offering plans with monthly premiums ranging from $5 to $99, Hylton said. There are several competing plans available from other providers, but local physicians and clinics have only agreed to work with two of them. Those companies’ premiums are scheduled to range between $116 to $231 per month.

“It’s cutting out the options for lower-income individuals to afford a Medicare Advantage health plan,” Hylton said.

A similar scenario played out last year when Atrio, another low-cost provider of Medicare Advantage plans, stopped offering coverage in Coos County.

The difference then was that CareSource stepped in and offered the low-cost alternatives. There isn’t another company rushing into the void this time, Hylton said.

Murray said he doesn’t know for sure what drove the company’s decision, but being a very rural county likely contributed.

Sennhauser said Care-Source customers will be eligible to go on Medicare supplement, which is similar to Advantage plans as it functions as secondary insurance for Medicare. Any company offering Medicare Advantage plans in Coos County will have to accept former CareSource customers, he said.

About a third of Medicare beneficiaries nationwide buy into an Advantage plan, Hylton said. It helps defray costs the public plan doesn’t cover, such as hospital stay deductibles, which can cost more than $1,000. The difference between Medicare supplements and the Advantage plan is that the latter serves as the primary insurance for customers, Sennhauser said.

“Advantage replaces Medicare,” he said.

The Medicare Advantage market has changed since 2008, when Congress passed the Medicare Improvements for Patients and Providers Act, said Stephanie Magill, a spokeswoman for Medicare Services.

The agency has worked with insurance companies to reduce organizations with low enrollment or duplicative plans. Magill wasn’t aware of the CareSource decision to leave Coos County, but said companies have been eliminating programs around the country.

“Most made business decisions to leave the program,” she said.