A 40-year study shows that people who suffer from chronic insomnia face a higher risk of dying.
Insomnia—difficulty falling asleep, staying asleep, or waking too early—is a common medical complaint that affects about 20 percent of adults in the United States. Chronic insomnia is estimated to occur in about half of those individuals.
Researchers analyzed data from a long-running respiratory study, the Tucson Epidemiological Study of Airway Obstructive Disease, which began in 1972 and has followed participants for decades.
The data show that chronic insomnia is associated with higher levels of inflammation in the blood and a 58 percent increase in risk of death.
Unlike intermittent insomnia, chronic or persistent insomnia that lasts for at least six years is associated with mortality. Moreover, greater levels of inflammation (measured by a biomarker in blood called C-reactive protein) and a steeper rise in such biomarkers of inflammation is associated with the persistence of insomnia and death.
Although other researchers have found a link between insomnia and death, whether this association holds true for both chronic and intermittent insomnia remains unknown. Many underlying mechanisms for why chronic insomnia may lead to death have been suggested but not been shown.
“An enhanced understanding of the association between persistence of insomnia and death would inform treatment of the at-risk population,” says Sairam Parthasarathy, associate professor of medicine at University of Arizona.
“We found that participants with persistent insomnia were at increased risk of dying due to heart and lung conditions independent of the effects of hypnotics, opportunity for sleep (as distinguished from sleep deprivation), sex, age, and other known confounding factors.
“Although there were higher levels of inflammation and steeper rises in inflammation in individuals with persistent insomnia when compared to those with intermittent or no insomnia, more research into other pathways by which persistent insomnia may lead to increased mortality needs to be explored,” says Stefano Guerra, research associate professor of medicine.
“Such biomarker-based research could potentially help advance precision science in predicting future clinical outcomes in patients with insomnia.”
Source: University of Arizona