By Amanda MacMillian, Health.com
updated 7:19 AM EST, Thu September 1, 2011
(Health.com) – People who have trouble sleeping rarely see their problem as an illness that requires treatment, or as an acceptable reason to call in sick. That mind-set may be hurting employers and employees alike by compelling people with insomnia to drag themselves to work and sleepwalk through the day, a new study suggests.
Researchers surveyed 7,428 employed people across the U.S. and found that 23% experienced some form of insomnia – such as difficulty falling asleep or nighttime waking – at least three times a week during the previous month, for at least 30 minutes at a stretch.
Not surprisingly, these sleep problems carried over into the workplace. Insomniacs were no more likely than their well-rested peers to miss work, but they were so consistently tired on the job that they cost their employers the equivalent of 7.8 days of work in lost productivity each year – an amount equal to an average of about $2,280 in salary per person.
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Those productivity losses add up. The researchers, projecting these findings to the entire U.S. workforce, estimate that poor job performance stemming from insomnia drains more than $63 billion from the nation's economy each year.
Most study participants did not physically miss work due to insomnia, says lead author Ronald Kessler, Ph.D., a psychiatric epidemiologist at Harvard Medical School, in Boston. More often, they showed up too tired to effectively do their job (a phenomenon known as “presenteeism”).
“Employers these days want their workers to stay home if they're sick. If they know you're absent, they can at least find ways to fill in for you,” Kessler says. “But you can't stay home every day if you're chronically sleep deprived, so these people get in the habit of going to work and then not performing.”
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.”
Kessler's study, published today in the journal Sleep, is an outgrowth of the American Insomnia Survey, a research project led by the World Health Organization (WHO) and Harvard Medical School that began in 2008. The survey and new study were funded, respectively, by Sanofi-Aventis (the maker of Ambien) and Merck, which is developing a new insomnia drug currently in the final phase of clinical trials.
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The companies were not involved in the collection or analysis of data, but they did provide advisory comments on the study manuscript. Kessler acknowledges the industry involvement may prompt some questions about the study's credibility, and stresses that more research on insomnia and productivity – including pilot programs in real-world workplaces – will be needed.
“What really needs to happen is for employers to set up programs in their own workplaces,” Kessler says. It may be cost-effective for companies to counsel workers with sleep problems, and provide behavioral therapy or medication if needed, he adds.
The survey sample was large but not nationally representative. Although the participants' ages and geographic locations mirrored the nation as a whole, all of the participants spoke English and had full health insurance through a large commercial health plan.
Insomnia rates were higher among women (27%) and lower among men (20%) and workers age 65 and older (14%). Previous studies have used narrow criteria to identify people with insomnia, but Kessler and his colleagues used the broadest possible definition of insomnia in order to capture people with relatively mild sleep problems who are nevertheless suffering at work.
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Productivity was measured using a WHO questionnaire. The study participants listed the number of workdays they'd missed, and ranked their own job performance on the days they'd been present.
It's not surprising that a lack of sleep was associated with poor performance, says Kushida, or that it failed to keep people home from work.
“Those with insomnia typically would have fatigue and tiredness, poor concentration, decreased memory, and mood changes,” Kushida says. Even so, he adds, “many people do not take sleep loss or its effects seriously, or they diminish its impact on their daily life.”
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Kessler agrees, but says he was still amazed by the amount of productivity lost to insomnia nationwide each year: more than 252 million days' worth.
“I've done these studies for years, and I've seen the obvious effects of conditions like depression and migraines,” he says. “But until recently, insomnia wasn't even on our radar screen.”
Insomnia is often overlooked because it tends to set in gradually and worsen slowly over time, Kessler says. People sense that they lack energy, but they don't realize it's because their sleep patterns have gotten worse and worse.
“Every convenience store sells energy drink shots, and every office has a coffeepot that we stagger to first thing in the morning,” he says. “Instead of trying to improve our sleep, we're trying to put something in our mouths just to get us through the day.”