I have vested interest here.. suffering long term fatigue ,brain fog,short term memory loss , just back from an MRI - now I know what it would sound like if you were a cockroach trapped in the guts of an inkjet printer
I don't use creatine but I do drink a lot of coffee
According to this study (press release below from the Journal of Alzheimer's Disease), it turns out "moderate" amount of coffee is 4-5 cups a day -- so I'm right in the sweet spot to ward off Alzheimer's!
It seems there are studies to "prove" about anything. Unfortunately, it's hard to be objective, with so many flawed studies around. Sometimes you have to simply observe what works best in your own life.