Insomnia is costing the country about 11.3 days on average per worker every year, according to a new study in the September issue of the journal Sleep.
The cost is $63.2 billion in lost productivity, or $2,280 per worker.
The results, funded by pharmaceutical companies, come from a national sampling of 7,428 employees and provide a clearer picture than existing estimates, derived from smaller samples or estimates based on those being treated for insomnia.
"We were shocked by the enormous impact insomnia has on the average person's life," said lead author Ronald C. Kessler, a psychiatric epidemiologist at Harvard Medical School's department of health care policy, in a statement.
"It's an underappreciated problem," Kessler said. "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 costs, he said, might justify screening and treatment programs for workers. Now, employers mostly ignore insomnia because it's not considered an illness.
Study authors said the average cost of treating the condition ranges from $200 a year for a generic sleeping pill to $1,200 for behavior therapy.
They estimated just more than 23 percent of workers have insomnia, and prevalence was lower among older workers and higher among women than men.
For more information, go to the American Academy of Sleep Medicine Web site's sleep blog at Sleepeducation.blogspot.com/search/label/insomnia or the Associated Professional Sleep Society Web site, Aasmnet.org.