I just was going through some of Alan's old posts.

Looks like he had a kidney transplant, a pancreas transplant, and had been a diabetic since 1983.

Obviously he had a lot working against him, healthwise. Knowing all of this, it is not all that surprising that he passed at the relatively young age of 70. Some people just have bad genetics and aren't destined to stay healthy. Considering all of these issues, making it to 70 wasn't all that bad.

RIP