NEW YORK (Reuters Health) – A survey from the United States and Canada found 40 percent of police officers had symptoms of a sleep disorder, including sleep apnea and insomnia.

Officers who screened positive for those disorders were also more likely to be burnt out, depressed or have an anxiety disorder. And over the next two years, they committed more administrative errors and safety violations and were more prone to falling asleep at the wheel than sound sleepers.

“In general we have this cultural attitude of, sleep is for the weak,” said Dr. Michael Grandner, from the Center for Sleep and Circadian Neurobiology at the University of Pennsylvania in Philadelphia.

“When you’re in an environment where signs of weakness are particularly discouraged, there may be a social pressure to not address sleep problems or to shrug them off,” added Grandner, the author of a commentary published with the new study in the Journal of the American Medical Association.

But when police officers in particular suffer from sleep problems, he said, it becomes a public health and safety problem.

“It’s not just the people with sleep disorders that are affected,” Grandner told Reuters Health. “If they’re impaired, you’re at risk.”

Researchers say police departments could do more to make sure that officers with sleep disorders get the appropriate treatment, which may include sleep machines, therapy or changes in work schedules.