Short Sleep Duration Common Among Redeployed Soldiers

FORT KNOX, Ky., Sept. 1, 2011 /PRNewswire/ -- More than seven of every 10 Soldiers suffer from short sleep duration, a chronic condition that increases risks for a variety of health problems, according to research results from the U.S. Army Medical Department, published today in SLEEP, a peer-reviewed journal of the Associated Professional Sleep Societies.

This first-ever study evaluating sleep deprivation and insomnia in service members returning from war showed that redeployed Soldiers commonly suffer from short sleep duration (SSD), defined in the study as less than seven hours per night. Short sleep duration is associated with, and may be a contributing factor to, a variety of common medical disorders following deployment, including major depression, post traumatic stress disorder (PTSD), mild traumatic brain injury (TBI), alcohol and tobacco abuse and attempted suicide.

With many Soldiers deploying multiple times, short sleep duration is common among active duty service members and likely persists between deployments. Various medical studies have shown that short sleep duration may contribute to physical and occupational impairments, including chronic pain, fatigue, depression, obesity, concentration or memory impairments and accidents at work or while driving.

This study sought to identify the prevalence of SSD in Soldiers who have returned home from deployment, determine if combat exposure predicted SSD up to 180 days after redeployment and examine the associations between SSD, medical co-morbidities and health risk factors.

"There are few published studies detailing sleep disturbances associated with war or traumatic events in service members," said Lt. Col. Vincent Mysliwiec, M.D., chief of Pulmonary, Critical Care Medicine and Sleep Medicine Service at Madigan Healthcare System, Joint Base Lewis-McChord, Tacoma, Wash. "Many Soldiers returning home from war have difficulty establishing a normal sleep pattern. Short sleep duration is highly prevalent in redeployed Soldiers and can negatively impact their lives.  

"Our findings provide evidence of increased risk of multiple co-morbid disorders among Soldiers who have short sleep duration. We did not determine if SSD preceded or was the result of the co-morbid disorders. However, addressing sleep early on in the course of PTSD, TBI and depression has the potential to improve outcomes in these difficult-to-treat disorders."

Researchers assessed the sleep habits of 3,152 Soldiers to compare the prevalence of co-morbid medical conditions with sleep duration. Study participants included Soldiers from a single redeployed brigade combat team who participated in a survey 90 to 180 days after completing a six- to 15-month deployment to Iraq.

The study measured sleep habits using two factors: the self-reported number of sleep hours per night and whether lack of sleep caused Soldiers to nap during the day or affected their job performance. Insufficient sleep was defined as a combination of these two factors.

Results showed the average sleep duration was 5.8 +/- 1.2 hours. Roughly 72 percent of Soldiers reported short or very short sleep duration (VSSD), receiving six or less hours of sleep each night, and 16 percent reported symptoms of insufficient sleep.

Of the respondents, 77 percent had experienced combat exposure and were much less likely to sleep more than six hours nightly. When controlling for combat exposure, SSD was associated with symptoms of depression, PTSD, panic syndrome and high-risk health behaviors, such as tobacco and alcohol abuse and suicide attempts.

The study revealed several associations of medical co-morbidities and health risks with sleep duration, including:

• The strongest predictor of PTSD was sleep duration of less than six hours per night. Symptoms of insufficient sleep were reported by 37 percent of Soldiers who met screening criteria for PTSD.
• Depression was strongly associated with sleep duration and symptoms of insufficient sleep.
• Mild traumatic brain injury was most strongly associated with combat exposure, but also with VSSD and symptoms of insufficient sleep.
• Obesity and tobacco and alcohol abuse were predicted by VSSD, but not SSD.
• Both panic syndrome and attempted suicide were associated with VSSD and symptoms of insufficient sleep.

The authors said their study points to the need for expanded screening for sleep disorders upon redeployment and additional educational, behavioral and clinical services for service members found to have a high prevalence of short sleep duration after deployment. These efforts may aid in the prevention and management of a variety of health risks and potentially minimize long-term health care utilization.

This study provides important evidence of "increased risk among Soldiers who experience sleep problems" and shows "the importance of addressing sleep disturbances as a separate disorder upon redeployment," said the authors.

David D. Luxton, Ph.D., David Greenburg, M.D. and M.P.H., Jenny Ryan, M.D., Alexander Niven, M.D., and Gary Wheeler, M.D., also participated in the study.

The U.S. Army offers two sleep medicine fellowship programs accredited by the Accreditation Council for Graduate Medical Education at Walter Reed Army Medical Center and San Antonio

Military Medical Center. Madigan Healthcare System is one of the largest health care systems in the military associated with a base and conducts 1,000 sleep studies each year.

About the U.S. Army Medical Department

One of the largest health care networks in the world, Army Health Care offers more than 90 professional health care career paths – more than any other military service. The U.S. Army's F. Edward Hebert Armed Forces Health Professions Scholarship Program is one of the most comprehensive health scholarships available today, and covers the complete cost of tuition, school fees and books, a monthly stipend of more than $2,000, as well as a $20,000 signing bonus for select areas of practice. Practicing physicians and health professionals can join the Army Reserve at any time in their career – up to age 60. For more information, visit www.healthcare.goarmy.com.

SOURCE U.S. Army Medical Department