Can Medicaid take the assets in a defined contribution plan or can the assets be used to buy a pension and Medicaid just takes pension?

My husband is retired on disability, which ends at age 65. Can we convert the assets in his defined contribution plan to an annuity or will Medicaid take the underlying assets if he goes to a nursing home. I know Medicaid will get the annuity payments, but will this be treated as a transfer to avoid Medicaid restrictions?