WASHINGTON -- Proposed cuts to a popular Medicare program would lead to sharp increases in costs for recipients, including many in Western Pennsylvania, Blue Cross and Blue Shield Association officials said yesterday.

Congress has already approved $13 billion in cuts for the Medicare Advantage program starting this year, and legislators are considering more reductions as they look to offset other spending priorities.

"Further cuts to the program would have absolutely disastrous consequences," said Alissa Fox, vice president of legislative and regulatory policy for the Blue Cross and Blue Shield Association. She warned of higher premiums, reduced benefits and fewer plans.

Medicare Advantage is provided through private insurers who receive payments from the federal government. It focuses more on "coordinated" care than traditional Medicare, helping seniors manage chronic illnesses such as diabetes. Nationwide, 8.3 million people are enrolled in Medicare Advantage.

In 29 counties of Western Pennsylvania, Highmark covers about 212,000 members through the program, making it the fourth-largest provider in the nation, according to Dr. Judith Black, the insurer's medical director for senior products.

Security Blue is the biggest of Highmark's Advantage plans.

Highmark already faces a funding gap this year because of past cuts.

It will only get a 1 percent increase in payments from the government, while medical expenses are expected to rise 8 percent, Dr. Black said.

Still, the financial outlook has been good in other ways for the region's largest health insurer. Highmark's controversial surplus swelled by about 12 percent in 2005, to $2.8 billion -- driven in part by health-care enrollment increases, lower-than-expected increases in health-care claim costs and continued growth in its dental, vision and life-insurance subsidiaries.

Critics argue that Medicare Advantage is inefficient, costing significantly more per beneficiary than traditional Medicare, draining scarce federal money. But insurers describe that argument as a misleading comparison, because Advantage plans include programs for targeting long-term illnesses.

Highmark, for instance, emphasizes colorectal cancer screening and helps seniors manage diabetes with "health coaches," representatives available by phone 24 hours a day. Highmark also has the Silver Sneakers program, which offers Advantage recipients free health club memberships and encourages seniors to maintain their health through regular exercise.