No you do not have to amend the corresponding Federal tax returns for the years you amended your Maryland state tax returns. The deduction you amended your state returns for was a state deduction and has not impact on your Federal return at all.
If you claimed the Standard Deduction on your Federal return for the years you amended your Maryland returns, the 1099-G income is not taxable income on your Federal tax return and does not need to be reported.
Even many taxpayers that claimed Itemized Deductions in 2017 and before began claiming the Standard Deduction in 2018 after the Tax Cuts and Jobs Act of 2017 dramatically increased the amount of the standard deduction for all filing statuses.
If you did claim Itemized Deductions for any of the years you amended your Maryland tax returns, you can compute the amount of any taxable Federal income from these refunds using Worksheet 2 in IRS Publication 525
