Drugs

He only had a brief problem with Heroin in the 80s. Apparently it was bad enough that Keith (of all people) told him to get it together!!

When Keith Richards tells you you have a drug problem.........you REALLY have a drug problem!!!!

He made it to eighty, which isn't bad, and exceeds the average longevity expectation. But yeah, he probably would've lasted longer without the past vices.