This is a subject near and dear to me since its had such a destructive effect on my life and my children's. I've always wondered whether mentally ill people were drawn to the religion or whether the religion was a causative factor in developing such. I don't know, but I suspect its a little bit of both.
Remember all those experiences where the person was in the midst of suicide preparations and a dub came calling? And then all was well. Sounds like the religion draws in people with some pretty severe problems. On the other hand, I have some experience with delusional dubs and its all about the religion.
Also, its such a depressing, guilt-ridden place that Mary Poppins might consider wrist slitting. On the other hand, I know some mentally ill people who I think do better in the religion. Adds some structure to their life. And so on. Like I said I can't come to any firm conclusion. I can say unequivically (SP?) that my current circle of friends and acquaintances has nothing like the incidence of depression and other assorted mental illnesses I found in my witness 'friends'.
Just a pedantic note. Correlation is not causation. It takes more than that. Most of the outrageous claims of the day are based on that particular weakness of the human mind.