That was true for people who reported symptoms of chronic insomnia versus those without insomnia.
Chronic insomnia was defined as experiencing difficulty falling asleep, problems getting back to sleep, awakening repeatedly or waking too early. These symptoms occurred more than five times per month.
Scientists say it's not clear whether insomnia may be having a direct effect on mortality or whether it's the insomnia interacting with other chronic conditions that leads to an earlier death.
The study was presented at the annual "Sleep" meeting in Texas.
