Lets' see, I have three potentially fatal (physical)'health issues'(two of them since birth; one of them is extremely common, but widely unknown). All three have no cure. I participate in two sports(bowling, bicycling). One is a very sedate sport. Could it kill me? Yes, If someone drops a 16pd. bowling ball on my head. One is a very aerobic sport. Could it kill me? Yes, Either by my own doing(not keeping control of my bike), or that of someone else not controlling their vehicle.
Do I stew over the possibility, no.
Watch '1001 Ways To Die', on the Spike cable channel.