Deployment to Iraq and Afghanistan significantly influenced sleep quality and quantity in a population of 41,225 military service personnel, according to new research. The study suggests that the promotion of healthier sleep patterns may be beneficial for military service members.

Results show that participants who completed a follow-up survey during deployment were 28% more likely to report having trouble falling asleep or staying asleep than those who had not yet been deployed; participants who completed follow-up after deployment also were 21% more likely to have trouble sleeping.

"This is the first large-scale, population-based study of sleep patterns in the military," said lead author Amber D. Seelig, data analyst for the Department of Deployment Health Research at the Naval Health Research Center in San Diego. "The primary finding of this study is that deployment does appear to affect sleep patterns in our population."

Participants were more than two times more likely to report trouble sleeping if they had baseline symptoms of mental health problems such as posttraumatic stress disorder or depression, or if they rated their general health as only fair/poor. The deployed and postdeployment groups also reported sleeping significantly less than the nondeployed group; however, the association between deployment status and sleep duration was no longer significant after adjustments for follow-up mental health conditions and combat exposure.

"We identified potential mediators, combat exposures, and mental health disorders, for the relationship between deployment and trouble sleeping," said Seelig.

According to the authors, sleep disturbances commonly co-occur with mental health conditions. They speculated that enhancing the quality and increasing the quantity of sleep during and after deployment may be one way to potentially reduce the occurrence of mental health problems in military personnel.

The findings appear in the December 1 issue of the journal SLEEP.