Not everyone who gets insomnia will eventually get depression. The next step is to try treating young patients who aren't depressed yet, but have a family history of depression and are having sleep disturbances.

I enjoy the acuteness of situations. I enjoy treating patients and not waiting. I like to be able to have my patients under my hand. I feel bad when they go home. I want to know what's going on. I want to call them the next day and make sure everything is OK.

We've known that sleep disturbances are among the best biological markers for depression, but this is the first time we've shown that those disturbances can show up decades before the depression.

Even after we compensated for confounding factors like family history of depression, coffee drinking, or their year in medical school, we still came out with a very clear change in risk.

It's a first step. It's not a total shutdown.

I'm not worried about it at all. A lot of times it gets blown out of proportion.