Work as a police officer -- which, for many, includes shifts during non-daytime hours -- could negatively impact sleep, a small new study shows.
University of Iowa researchers found that police officers who worked during the nights or evenings were 14 times more likely to get fewer than six hours of sleep a a day, compared with people who worked days.
Plus, the police officers who got fewer than six hours of sleep a day had more than a doubled risk of bad quality sleep, compared with those who got six or more hours of sleep a day, the Workplace Health & Safety study said.
"This study further confirmed the impact of shift work on law enforcement officers and the importance of sleep as a modifiable risk factor for police," study researcher Sandra Ramey, an assistant professor at the University of Iowa, said in a statement.
The study included surveys from 85 male police officers, between ages 22 and 63, who were part of three different Iowa police departments and worked about 46 hours a week, on average. Researchers were sure to get an equal number of dayshift workers as night- and evening-shift workers. All of the study participants were asked about their stress and fatigue levels, and their height, weight and C-reactive protein levels (a sign of inflammation) were also measured.
The researchers spotted some trends among the officers. For one, 83 percent said they have had to, at least on occasion, get up early for work the next day after working a night or evening shift.
The researchers also noted that they did not find a link between poor sleep and health problems, but they said that the study sample size may have been too small to spot any that may exist. Past research has linked poor sleep and too little sleep with health problems like Alzheimer's disease and memory problems, weight gain and diabetes.
Recently, a similar study on sleep and health in police officers was published in the International Journal of Emergency Mental Health.
In that study of 464 Buffalo (NY) Police Department officers, researchers found that almost half worked the night shift (a significantly higher percentage than the rest of the U.S. population, of which 9 percent does shift work). And this shift work was linked with an increased risk of metabolic syndrome. That condition is comprised of a group of conditions, including excess body fat, high cholesterol and an increase in blood pressure or blood sugar levels, according to the Mayo Clinic.
And last year, a study of nearly 5,000 police officers in the Journal of the American Medical Association showed that as many as 40 percent of police officers don't get enough sleep and have some sort of sleep disorder, ABC News reported.
"We know that sleep deprivation results in impaired performance both cognitively, physically and emotionally, which can impact decision-making and response time, which are crucial to high stress professions such as law enforcement," Dr. Nanci Yang, a Stanford University professor not directly involved in the study, told ABC News. "It is paramount to public safety that it be addressed."