DETROIT — Gloria Killebrew, 73, worked for the City of Detroit for 22 years and now spends her days caring for her husband, J. D., who has had three heart attacks and multiple kidney operations, the last of which left him needing dialysis three times a week at the Henry Ford Medical Center in Dearborn, Mich.

Now there is a new worry: Detroit wants to cut the pensions it pays retirees like Ms. Killebrew, who now receives about $1,900 a month.

“It’s been life on a roller coaster,” Ms. Killebrew said, explaining that even if she could find a new job at her age, there would be no one to take care of her husband. “You don’t sleep well. You think about whether you’re going to be able to make it. Right now, you don’t really know.”

Detroit’s pension shortfall accounts for about $3.5 billion of the $18 billion in debts that led the city to file for bankruptcy last week. How it handles this problem — of not enough money set aside to pay the pensions it has promised its workers — is being closely watched by other cities with fiscal troubles.