About 327,000 of the 6.2 million Medicare beneficiaries nationwide who belong to HMOs will be abandoned by their health plans next year, the government said yesterday.

Of those, 79,000 will be unable to enroll in another health maintenance organization as 41 health plans withdraw from the federal health insurance program for the elderly and disabled and another 58 stop serving Medicare beneficiaries in particular areas, according to the agency that runs Medicare.

Medicare beneficiaries who lose their HMO coverage have two or three alternatives: They can choose another HMO, if one is available; they can revert to standard fee-for-service Medicare coverage; and they can buy "Medigap" policies to supplement the standard benefits.

But there is no guarantee that they can find a Medigap policy with prescription drug coverage, which is one of the main reasons some Medicare beneficiaries choose HMOs.

In Maryland and Virginia, 33,000 beneficiaries--26.9 percent of those with HMO coverage--will lose their current coverage, and 27,000 will be unable to replace it with another HMO.

An HMO industry group recently predicted that more than 250,000 beneficiaries would be affected by the changes, but the Department of Health and Human Services released the final tally based on notices HMOs were required to submit by July 1.

This year, a larger number of beneficiaries--407,000--were abandoned by their HMOs, but a smaller number--51,000--were left without an HMO option.

The managed-care industry says HMOs are pulling out of Medicare because the government isn't paying them enough, but the government says the HMOs' actions reflect broader industry trends.