Any use of a GPU will effect it's lifespan. What you meant to ask is, does mining have more of an effect than "normal" use. The fact of the matter is you cannot tell, unless you have lots of data concerning how the card was used during it's mining period of use. I could be no more worse than gaming everyday at 1080P, or it could be vastly worse. It also depends on the quality of the card itself, and power that was supplied to the card. In general, the hours put on the card are going to be much more than your typical usage scenario, so for the sake of argument, mining typically "uses up" a card faster than a non-mining usage scenario.