An era of higher interest rates — with the 30-year U.S. Treasury bond reaching 5.609 percent, its highest yield since 2002 — generally is good news for savers, as banks may increase payouts on savings accounts or newly issued certificates of deposit. But many seniors may not realize that rising rates could hit them in other ways, including higher Medicare premiums or reduced health-insurance subsidies. Some Social Security beneficiaries may also face a surprise tax bill.
