Does Undergoing Dialysis Cause Memory Loss?

My dad is 84 years old and has just started dialysis's about 4 months ago. We've all noticed that his memory is really bad now. It started with just a couple of things. But now he's driving and he will ask. where is it that I am going. He's been driving for years,so that's why he still driving ..... and was doing fine, until now...Is Memory loss normal for the dialysis ?