yes and no.
It will not affect your score.
That said, it will turn into a charge off and then eventually a collection and probably a judgement or lawsuit down the road if the balance is very high sonwballing into a much worse situation that it is now..
It could also affect any future plans as far as mortgages and such if you look to buy a house in the next 2-3 years in particular.
Prior to walking away form the card, I would tell your husband to call the creditor and have them close the account and work out a deal to pay the balance off at a reduced amount and interest over an extended period. This wouldbe much better than walking away and cheaper than if it does end up going to a lawyer.
All this assumes that it is a fairly high balance or you guys would just work to pay it off normally as obviously leaving the account open, not using it, and paying it off is the best scenario.