While sleep disorders plague many Americans, police officers may fare worse than others, according to a new Brigham and Women’s Hospital study that found 40 percent have a chronic sleep problem, which in most cases had not been diagnosed.
The national study published yesterday found that 26 percent of the officers reported that they fall asleep driving at least once a month because of excessive drowsiness.
Massachusetts State Police officers, however, had markedly lower rates of sleep problems such as obstructive sleep apnea, insomnia, and shift work sleepiness - most likely, the researchers said, because of a mandatory fitness test they must pass every two years to hold onto their jobs.
Police officers with sleep disorders were more than twice as likely to have depression, anxiety, and job burnout than those without, and they were three times more likely to fall asleep at the wheel, according to the study in the Journal of the American Medical Association.
The researchers took into account other factors that could cause psychological problems like having a second job, alcohol consumption, and total number of hours worked.
“The sleep disorder statistics for police officers nationwide are much higher than what’s been reported in the general population,’’ said Dr. Charles Czeisler, study author and chief of the division of sleep medicine at Brigham.
Czeisler pointed to a higher rate of obesity among officers compared with the general population as a major factor, since sleep apnea has been linked to excess body weight.
Michael Grandner, a sleep researcher at the University of Pennsylvania who wrote an editorial that accompanied the study, said in an interview that police officers often spend much of their time “sitting behind desks or the wheel of a car.’’
“The lack of activity coupled with the high stress of dealing with criminals could explain the higher obesity rate,’’ he said.
This is not the case, though, for Massachusetts State Police, whose average body weight is lower than the average American’s and who may have fewer sleep problems as a result. Slightly more than 1 in 5 officers who participated in the study were obese compared with about 1 in 3 Americans and more than 1 in 3 police officers nationwide.
While Massachusetts enjoys the fourth-lowest obesity rate in the nation, Czeisler said the State Police on-the-job fitness program, one of a handful in the country, probably also plays a key role.
Two decades ago, the Legislature mandated that State Police officers periodically pass a fitness test, consisting of dragging a dummy in a rescue mission and taking down a suspect by scaling walls and running through an obstacle course.
To get and stay in shape for the test, police are allowed to set aside four hours of work time every week to exercise in a local fitness facility or gym onsite. They can also earn bonuses for their test performance.
Sergeant Rick Brown, president of the State Police Association of Massachusetts, said he was excited about the study findings, which he said demonstrated that the fitness regimen - which he helped develop - was having an impact.
“How else can you explain the differences?’’ he said.
But Brown also said the state force has done little to address night shift work, which the study found causes insomnia and on-the-job sleepiness in 7 percent of the Massachusetts State Police workforce.
“We’ve joked that night shift workers should be allowed siestas during their shifts,’’ he said. Officers with little seniority typically are assigned to work the graveyard shift for 56 days in a row, several times a year, he said.
Czeisler said officers should be educated to adjust to night shifts by, say, keeping the same sleep schedule even on their off nights or installing room-darkening blinds to shut out daylight when they need to sleep.
His study found that 34 percent of the 5,000 officers nationwide who participated in screening had signs of sleep apnea, compared with 20 percent of Massachusetts officers.
Nearly 7 percent of the national sample had moderate to severe insomnia, compared with less than 4 percent of the State Police.
The authors said they hope the findings alert police departments that they could be doing more to address sleep disorders and improve safety on the job.
“Sleep deprivation not only slows down reaction time but decreases a person’s ability to stay vigilant with focused attention,’’ Grandner said. “It also impairs the ability to make well thought out decisions’’ such as whether to shoot at a fleeing suspect or commence a car chase.
While the researchers did not collect data on the number of police and civilian injuries resulting from sleepy police officers, the National Highway Traffic and Safety Association estimates that drowsy driving, a widespread habit among all Americans, leads to 71,000 injuries and 1,550 deaths every year nationwide, with a sixfold increase in risk for those who work the night shift.
At a national transportation meeting last month, Czeisler urged government officials to institute widespread screening for sleep apnea for truckers, who get into frequent accidents from drowsy driving, and he said yesterday that he also supports such screening for police officers, because the condition goes undiagnosed most of the time. Such screening has not been implemented in Massachusetts.
“We plan to follow up on this study - the first of its kind to explore sleep apnea rates in a police department of this size - by continuing to make available information about sleep apnea and other sleep disorders to our personnel, sworn and civilian alike,’’ Colonel Marian McGovern, superintendent of the Massachusetts State Police, said in a statement. The department declined to make anyone available for an interview.
Brown recalled his own brush with drowsy driving, when he used to commute 85 miles roundtrip to and from a job at the police academy.
He said he pulled over whenever he felt his eyes starting to close. “Knock on wood, I have never fallen asleep at the wheel,’’ he said.