NEW YORK (Reuters Health) - People with insomnia who are actually getting very little sleep have a sharply higher risk of high blood pressure than their peers who have no trouble catching Z’s, new research shows.
The findings make it clear that insomnia can have real medical consequences, and is not just a disorder of the “worried well,” Dr. Alexandros N. Vgontzas, director of the Sleep Research and Treatment Center at the Penn State College of Medicine in Hershey, told Reuters Health.
About 1 in 10 people have insomnia, Vgontzas notes, but the health consequences of a much less common sleep problem, sleep apnea, have gotten a lot more attention. Previous research has shown, he added, that people with insomnia have higher levels of the stress hormone cortisol, greater activation of the sympathetic nervous system, and psychiatric problems such as anxiety and depression.
To investigate whether insomnia might also carry cardiovascular risks, Vgontzas and his team had 1,741 men and women spend a night in their lab to measure how long they actually slept. Self-reports of sleep duration, the researcher noted, are notoriously inaccurate.
Eight percent of the study participants reported having insomnia, defined as difficulty falling asleep that lasted for at least 1 year, while 22 percent had less severe sleep problems. The rest were normal sleepers. Lab testing showed that half of the study participants got at least 6 hours of sleep, about a quarter slept for 5 to 6 hours, and the rest slept for less than 5 hours.
Among the subjects with insomnia who slept less than 5 hours, the risk of high blood pressure was 50percent greater than for those who didn’t have insomnia and logged 6 hours or more of sleep. People with insomnia who slept 5 to 6 hours had a 350 percent increased risk of hypertension.
But the people with insomnia who slept for at least 6 hours had no greater risk of hypertension. People with less serious sleep problems who slept less than 6 hours also had an increased risk of high blood pressure, but it was lower than for the true insomniacs.
lasting for 1 year or longer. Poor sleep was defined as moderate to severe complaints of failure to fall asleep, not being able to stay asleep, and early wakening without a feeling of being rested. Subjects were defined as normal sleepers if they did not fall into either of the previous categories.
Right now, Vgontzas said, insomnia is typically treated with medication and psychotherapy. While the findings make it clear that people with insomnia and short sleep should take priority in treatment, he added, this doesn’t mean that people with insomnia who actually get relatively decent amounts of sleep shouldn’t be treated too.
Finally, he noted, while sending everyone with insomnia to the sleep lab would bankrupt the health care system, a technique called actigraphy in which a person wears a wristwatch-like device to measure their movements is an effective and much less expensive option for identifying people with short sleep duration.
SOURCE: SLEEP, April 1, 2009.