"We were shocked by the enormous impact insomnia has on the average person's life," said lead author Ronald C. Kessler, Ph.D. "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 computed from a national sampling of 7,428 employees, part of the larger American Insomnia Study, which was led by Kessler and funded by Sanofi-Aventis Groupe. Participants were asked about sleep habits and work performance, among other things. Previous estimates have relied on smaller consumer panels and on medical and pharmacy claims databases focused on treated insomnia patients, the study said.

The estimated prevalence of insomnia in the AIS sample was 23.2 percent among employees. Insomnia also was found to be significantly lower (14.3 percent) among workers age 65 and older, and higher among working women (27.1 percent) than working men (19.7 percent). Clinical sleep medicine experts independently evaluated a subsample of AIS respondents and confirmed the accuracy of those estimates.

Kessler said accurate estimates on the costs of insomnia in the workplace might justify the implementation of screening and treatment programs for employees. Because insomnia is not considered an illness -- the kind that results in lost days at work -- employers tend to ignore its consequences, he said.

"Now that we know how much insomnia costs the American workplace, the question for employers is whether the price of intervention is worthwhile," said Kessler, a psychiatric epidemiologist with the Department of Health Care Policy at Harvard Medical School. "Can U.S. employers afford not to address insomnia in workplace?"

Roughly speaking, the average cost of treating insomnia ranges from about $200 a year for a generic sleeping pill to up to $1,200 for behavioral therapy, according to study co-author James K. Walsh, Ph.D., executive director and senior scientist at the Sleep Medicine and Research Center at St. Luke's Hospital in Chesterfield, Mo.

The SLEEP study also found a lower than average insomnia prevalence among respondents with less than a high school education (19.9 percent) and among college graduates (21.5 percent). Those with a high school education (25.3 percent) or some college education (26.4 percent) showed higher rates of prevalent insomnia. The AIS survey was conducted in 2008 and 2009.

The study was sponsored by Merck & Co. The AIS was conceived of and funded by Sanofi-Aventis (SA) Groupe.

Note: If no author is given, the source is cited instead.

• Sleep Disorder Research
• Insomnia Research

• Sleep Disorders
• Insomnia

• Industrial Relations
• Public Health

• Sleep deprivation
• Insomnia
• Delayed sleep phase syndrome
• Circadian rhythm
• Detox diet
• Fatigue (physical)