Tens of thousands of state and county workers won't see a big jump in their medical insurance premiums next year as had been feared, with rates to remain unchanged through June 30.

Trustees for the state Employer-Union Health Benefits Trust Fund yesterday voted to keep the current rates in place rather than act on a 13.6 percent rate hike suggested by a consultant.

The action affects workers receiving coverage under Hawaii Medical Service Association and HMA preferred provider plans and HMSA's health maintenance organization plan. The EUTF has yet to announce what will happen with premiums for Kaiser Permanente's HMO plan.

"They're aware that the consultant is projecting a loss of about $2.7 million a month beginning in January," said Jim Williams, EUTF administrator.

"But the EUTF has the cash to pay for that. It will affect our balance sheet but we do have the cash."

He said one factor in the trustees' decision was recent medical and drug coverage rate increases for the workers. In July, the amount paid by many members for coverage for families under preferred provider plans jumped to $348.20 a month, with the EUTF prescription drug plan rising to $78.44.

That increase amounted to an average 23.4 percent hike in medical premium costs for members and was a factor in the trustees' decision, Williams said.

"That's why the trustees are reluctant to add anything on top of that because it's going to be a hardship on employees," Williams said.

The EUTF's decision comes against the backdrop of contract negotiations between the state and worker unions in which there has been talk of increasing the percentage of overall cost that employees pay. The state now pays for 60 percent of the premium costs.

The trustees also voted to approve a new offering in the EUTF's preferred provider plans. These are known as 90-10 plans under which employees pick up 10 percent of the cost of visits to doctors and other health care providers, with insurance picking up the remainder.

Instead of having HMSA and HMA both providing 90-10 plans, the trustees approved HMA continuing to have a 90-10 plan, while a new offering through HMSA, an 80-20 plan, will be in effect starting next year. People opting for the HMSA coverage will pay twice as much in out-of-pocket costs, but premiums will be 3.4 percent lower.

Williams said workers will be given an option to selecting which plan they want, including Kaiser, HMSA and HMA, during an open enrollment period next month.

HMA, which is affiliated with Summerlin Life and Health Insurance Co., said it hopes to pick up more members because people who want to stick with a 90-10 plan will default to its coverage.

"This is a great opportunity," said Harris Nakamoto, Summerlin vice president and general manager. He said his company recently increased its membership ranks when it offered a plan for teachers, picking up coverage of 6,000 members while HMSA only signed up 3,000 for its plan offered to the group.