Daniel Negreanu wrote about this in his book Power Hold'em Strategy, where he says that he would NEVER fold kings in fear of running them into aces preflop. If you do, its just a cooler but he says that doesn't justify folding them.
I found another site which makes a more interesting and nuanced claim... I'll quote it:
"The odds of somebody having pocket AA when you have pocket KK in a full ring game is 4.32%. However, in a 6 person poker game the odds drop sharply to only 2.88%. The reasons for this are pretty simple of course. More people at the poker table means more opportunities for somebody to have the one hand that beats your cowboys. So as a general rule I am just not going to be finding a fold before the flop with pocket kings in a 6max poker game, but I will think about it in a full ring game."
As is my norm, I won't post a direct link to that article but if you want to look it up, it is entitled "You Need to Fold Pocket Kings Preflop in This ONE Situation" on the blackrain79 website.
tl;dr Some say never fold KK pre, others say you can consider folding at full ring if villain is raising from early position, and I will add, if you consider your opponent to be an absolute rock (OMC type, Old Man Coffee).
Edit to add: I see he (Nathan Williams) also has a youtube channel (BlackRain79Poker) and he made a video on this topic, "Should You Ever Fold Pocket Kings Preflop?" for those interesting in digging it up and watching it. Just for the record I am not Nathan nor do I know him.
But he seems competent enough in explaining this topic.