Right on, Finals40, but don't forget neoplasia and polycythaemia/thombocythaemia. I agree that maintaining a good level of hydration ,exercising the lower limb muscle groups and avoiding alcohol should be the first line of protection for both crew and passengers.
In todays litigous society I am afraid this issue is not going to go away even though it is probably an unavoidable risk of flying. Compare with road accidents - some risks have to be accepted