In the study (subscription required), researchers surveyed 7,428 employees about their sleep habits and work performance as part of the American Insomnia Survey, a research project launched by the World Health Organization and Harvard Medical School in 2008. Results showed 23 percent of participants experienced some form of insomnia, which cost their employers the equivalent of 7.8 days of work in lost productivity each year or roughly $2,280 in salary per person.
About one-third of all U.S. adults experience weekly difficulties with nighttime sleep, and an estimated 50 to 70 million people complain of associated daytime impairment, the study notes. And while it's hard to compare past and present research, insomnia does seem to be on the rise, says Clete Kushida, MD, a neurologist and sleep-medicine specialist at the Stanford University School of Medicine, in Palo Alto, Calif.
"There appears to be more insomnia, given more work and family responsibilities, and more technological improvements and distractions," says Kushida, who was not involved in the new study. "These result in more stress that can precipitate worsened sleep."
This study was funded by drug companies Sanofi-Aventis and Merck.
Previously: Stanford sleep expert offers evaluation of science behind one sleep device, CDC report highlights the dangers of sleep deprivation, Sleep deprivation more common in the U.S. than Europe and National poll reveals sleep disorders, use of sleeping aids among ethnic groups
Photo by Warren Noronha