Yes, you're right. And the fact that Generation X's are now doing those surveys, not just the baby boomers means you're getting a whole new generation of people more open to discussing their issues, hence the increase. But always rmember, it's just one survey out of millions and they all say different things and hypothesize over different theories.
By the way, my comment about the internet was misinterpreted. I meant that if you look on the internet, you can find a lot of research on this subject and health issues are a huge cause.