At 4K, your graphics card would have to render four times the pixels of 1080p, which would greatly reduce performance. Unless you were to upgrade to a very high end graphics card like a 1080 Ti, performance with high graphics settings at 4K in a demanding game like that would be more or less unplayable. You might be able to turn graphics settings way down to manage 4K on that graphics card, but that would make the game look significantly worse, entirely defeating the purpose of rendering it at a higher resolution.
Of course, you could still run the game at 1080p on a 4K screen, but I suspect that is not what you're looking for.