The cuts will mean turmoil and confusion for many beneficiaries, as well as the risk of higher premiums, fewer benefits or both.

Humana shares slid after the health insurer said it expects Medicare Advantage memberships to decline in 2025 before the market opened Tuesday.

Humana depends more than other insurers on revenue from Medicare Advantage, private versions of the government’s program for older and disabled people. Investors are concerned about the long-term results from the business as the government has lowered Humana’s quality ratings, called stars, that affect future payments.