The death risk is even higher -- over seven times the normal death rate -- for insomniacs with underlying diabetes or with high blood pressure, find Penn State researchers Alexandros. N. Vgontzas, MD, and colleagues.
Increased death risk was seen only in self-described insomniacs who, when tested in a sleep lab, slept less than six hours a night. People who said they did not have insomnia but who slept less than six hours a night did not have a significantly increased death risk. Neither did self-described insomniacs who slept more than six hours in the lab.
The findings come only from the men in the study. What about women? The jury is still out. The researchers began studying women five years after they began studying men. And since women tend to live longer than men, final results for women are not yet in.
"This is a very important study," sleep expert Lisa Shives, MD, medical director of Northshore Sleep Medicine, Evanston, Ill., tells WebMD. Shives, a spokeswoman for the American Academy of Sleep Medicine, was not involved in the Vgontzas study.
New Insomnia Treatments Needed
Shives notes people with insomnia tend to be in a constant "flight-or-fight" stress mode.
"We are supposed to have seven or eight hours every night with the body in a quiescent mode," she says. "Our heart rate, our blood pressure is lower, our sympathetic nervous system -- the flight-or-fight system -- all that is supposed to be dampened down. But think of someone who is unable to get this, who is under all this cardiovascular stress. We call that insomnia."