Leo Sher, M.D.

Sleep disturbances are an important concern in combat veterans (1-4). Disordered sleep is the most common presenting problem among veterans with posttraumatic stress disorder (PTSD) (2). A history of traumatic brain injury (TBI) is also associated with sleep abnormalities (3). Considerable evidence suggests that sleep disorders may affect cognitive functioning (1,5-7). The Medical Dictionary defines cognitive function as “an intellectual process by which one becomes aware of, perceives, or comprehends ideas. It involves all aspects of perception, thinking, reasoning, and remembering” (8).

Researchers from North Carolina and Texas examined how sleep quality alters cognitive functioning in combat veterans and reported the results of their study in a recently published paper, “Sleep quality affects cognitive functioning in returning combat veterans beyond combat exposure, PTSD, and mild TBI history” (1).The researchers conducted a cross-sectional assessment study evaluating combat exposure, PTSD, mild TBI history, sleep quality, and neuropsychological functioning.
 
The authors found that sleep quality influenced cognitive function independently of combat experiences, PTSD, and mild TBI history. They also observed that sleep quality contributed to cognitive deficits beyond effects of PTSD. The researchers also suggest that future studies should use a physical measure (such as wrist actigraphy) of sleep quality that would provide an objective measure of sleep characteristics. Improving sleep quality is an important clinical intervention in combat veterans with cognitive problems.

References

1.    Martindale SL, Morissette SB, Rowland JA, Dolan SL. Sleep quality affects cognitive functioning in returning combat veterans beyond combat exposure, PTSD, and mild TBI history. Neuropsychology 2017;31(1):93-104.
2.    Orr N, Carter K, Collen JF, Hoffman M, Holley AB, Lettieri CJ. Prevalence of sleep disorders among soldiers with combat-related posttraumatic stress disorder. Chest 2010; 138:704A.
3.    Lucke-Wold BP, Smith KE, Nguyen L, Turner RC, Logsdon AF, Jackson GJ, Huber JD, Rosen CL, Miller DB. Sleep disruption and the sequelae associated with traumatic brain injury. Neuroscie Biobehav Rev 2015; 55: 68–77.
4.    Bramoweth AD, Germain A. Deployment-related insomnia in military personnel and veterans. Curr Psychiatry Rep 2013;15(10):401. doi: 10.1007/s11920-013-0401-4.
5.    Mueller AD, Meerlo P, McGinty D, Mistlberger RE. Sleep and adult neurogenesis: implications for cognition and mood. Curr Top Behav Neurosci 2015;25:151-81.
6.    Waters F, Bucks RS. Neuropsychological effects of sleep loss: Implication for neuropsychologists. J Internat Neuropsychol Soc 2011;17:571–586.
7.    Walker MP. The role of sleep in cognition and emotion. Ann N Y Acad Sci 2009;1156:168-197.
8.    http://medical-dictionary.thefreedictionary.com/cognitive+function