Stress may increase risk for [fill in the blank].
Isn't that the truth. And if it doesn't increase the risk, then it probably exacerbates the disease you have.
I have MS, and a neuro will tell you to "avoid stress." Now, seriously, how do you live life, apart from turning into a recluse and refusing to have any interaction with people or relatives, without having stress in your live.
Managing stress, probably possible; avoiding stress, impossible.