Uncle- I don't know about mortality statistics, but our suicide and divorce rates are just plain atrocious, especially for us psychiatrists. Some of that is selected, no doubt. Some people are led to psychiatry by having psychiatric illnesses, and some of us die of major depression and manic-depressive illness.
The 24/24 schedule isn't so bad as you would think (which isn't to say it's good!). My worst was every 3 days on call, with no days off between. Usually I'm pretty easy to get along with; by the end of that month I was just plain vile.
That's the worst part of the whole thing, really. The stress, lack of sleep, things you could've done but were too tired or didn't think about in time, etc., etc. build up and they can change you, often not for the better. When it's all over you're left with having snapped at your girlfriend, neglected things because you were tired, and so on. That can be hard to let go, and it's not pleasant to reflect on how much you can change without wanting it.