"We were shocked by the enormous impact insomnia has on the average person's life," lead author Ronald Kessler, a psychiatric epidemiologist and professor of healthcare policy at Harvard Medical School, said in a statement. "It's an underappreciated problem. Americans are not missing work because of insomnia. They are still going to their jobs, but accomplishing less because they're tired. In an information-based economy, it's difficult to find a condition that has a greater effect on productivity."
The results were calculated from a national sampling of 7,428 employees, part of the larger American Insomnia Study, led by Kessler.
The estimated prevalence of insomnia in the sample was 23.2 percent among employees. Insomnia was found to be significantly lower among workers age 65 and older, and higher among working women than working men, the study said. Clinical sleep medicine experts independently evaluated a sub-sample of respondents and confirmed the accuracy of those estimates.
"Now that we know how much insomnia costs the American workplace, the question for employers is whether the price of intervention is worthwhile," Kessler said in a statement. "Can U.S. employers afford not to address insomnia in the workplace?"
The average cost of treating insomnia ranges from about $200 a year for a generic sleeping pill to $1,200 for behavioral therapy, study co-author James K. Walsh, senior scientist at the Sleep Medicine and Research Center at St. Luke's Hospital in Chesterfield, Mo.