There are technically no Nobel Prize winners in economics. I think that's what the comment was talking about. The economics prize is not a Nobel Prize as established by Alfred Nobel, it is the Nobel Memorial Prize in Economic Sciences [1], established in 1968 by the Swedish National Bank. It is grouped with the others and awarded in the same ceremony, however.
1. https://en.wikipedia.org/wiki/Nobel_Memorial_Prize_in_Econom...