According to preliminary results of a new study, there is a high prevalence of insufficient sleep and symptoms of common sleep disorders among medical center nurses.

Results show that 49% of participating nurses at an academic medical center averaged less than 7 hours of sleep per night, and the overall average nightly sleep time was 6.6 hours. Symptoms consistent with chronic insomnia were identified in 31% of nurses, and excessive daytime sleepiness was found in 4.5% of them. Twenty-seven percent of nurses used medications to help them sleep, and 13% reported using medications to stay awake. Symptoms indicative of shift work disorder were present in 31% of nurses. About 18.5% of nurses also had a moderate-to-severe risk for obstructive sleep apnea.

“We were surprised by the number of nurses potentially suffering from common sleep disorders, most notably, chronic insomnia and shift work disorder,” said lead author Francis Christian, MD, a second-year fellow at the University of Oklahoma Health Sciences Center in Oklahoma City.