Women have PLENTY of health issues to deal with. It's all a matter of what you're most worried about. As other guys have said, testosterone only shortens your life in that it makes your life expectancy that of a male instead of a female. If you'd been born male to begin with, you'd already be dealing with that. The only problem being on T can cause, beyond putting you at the same risk for things as any guy, is liver problems... the introduction of any drug/hormone/whatever can cause that. That's why they don't prescribe oral T unless it's absolutely necessary. Regular medical tests, though, should keep you from having any big problems... you'll be able to fix pretty much anything if you catch it early enough.
Actually, as far as women living longer than men in general, it's just a wonderful fact of life that women are, despite all outside appearances, stronger than men. It's in the genes. 90% of babies conceived are male, and yet only 50% of births are male. Why is that? Males are at a far higher risk of death in utero. The majority of stillbirths are male, as are miscarriages. If you think about it, even though men do a lot of the grunt work in the world, traditionally, it's women who have the biggest job: carrying children, continuing the species. Pregnancy and childbirth take a massive toll on the human body... a toll that the male body simply could not handle, by design.
Honestly, I wonder if despite ftms going from estrogen to testosterone, do we still retain that female strength? Haha. Maybe we're all just supermen.
SD