Insomnia Symptoms Predict Posttraumatic Stress Symptoms in the Warfighter: A Study of a Simulated Deployment Training Operation 1
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Maria E. St. Pierre, MA ; Lillian Skeiky, BS ; Jake J. Choynowski, BS ; Julie C. Merrill, MA ; 1 1 Ashlee B. McKeon, PhD ; Walter J. Sowden, PhD 1
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Behavioral Biology Branch, Center for Military Psychiatry & Neuroscience; United States Army Medical Research Directorate– West
BACKGROUND
RESULTS
Shortened sleep duration (SD) and insomnia symptoms have been extensively
linked to adverse psychological health outcomes. Poor sleep health and sleep disturbances experienced by Service Members may increase risk for acute stress responses (e.g., posttraumatic stress symptoms [PTSS]) in the operational environment and therefore, may compromise Soldier readiness and resilience. Scientific shift over the last decade where sleep problems, once thought to be a symptom of PTSD, are now believed to share a more bi- direction relationship with PTSD. This study characterized and tested predictive relationships between self reported sleep health, sleep disturbances, and PTSS in a large military unit before and after a simulated deployment training operation in support of subsequent combat operations.
Objective 2: Prediction of Disturbed Sleep on PTSS
Objective 1a: Characterizing Sleep & PTSS Pre- Training SD
ISI
Post- Training PCL-4
SD
ISI
PCL-4
RANK E1-E4
5.51 (0.07) 5.50 (0.35)
9.23 (0.16)
5.48 (0.08)
5.70 (0.37)
10.28 (0.24)
E5-E6
5.32 (0.12) 6.44 (0.58)
9.68 (0.30)
5.08 (0.14)
6.90 (0.68)
10.44 (0.39)
E7-E9
4.85 (0.25)* 5.45 (1.19) 10.26 (0.80) 4.74 (0.25)*
5.58 (0.94
9.17 (0.58)
Officers
5.61 (0.17) 6.07 (0.81)
5.68 (0.61)
9.38 (0.34)
9.43 (0.30)
5.79 (0.17)
YEARS IN THE MILITARY
METHODS National Training Center (NTC) is an extensive and immersive mission readi-
ness exercise simulating deployment operations that Soldiers will experience in combat zones. - Multiple Integrated Laser Engagement System (MILES) - 15-day training simulation 427 US Army Soldiers (24.9 y/o ± 5.57; 89% male) completed a self-report survey on sleep and psychological health before and after NTC: Insomnia Severity Index (ISI) items, SD extracted from the Pittsburgh Sleep Quality Index (PSQI), and the Posttraumatic Stress Disorder Checklist-Military Version, fouritem version (PCL-4) Objective 1a: Characterized sleep health and PTSS at pre- & post- training Objective 1b: Examined pre- & post-training differences Objective 2: Tested the prediction of disrupted sleep on PTSS
Recently Joined
5.87 (0.19) 4.32 (0.77)
8.56 (0.28)
5.70 (0.22)
5.88 (0.92) 11.44 (0.67)*
1-10 years 5.42 (0.07) 6.15 (0.31)
9.34 (0.15)
5.38 (0.08)
5.91 (0.34)
9.96 (0.20)
5.22 (0.14)* 6.40 (0.65) 10.08 (0.41)* 5.00 (0.17)* 6.11 (0.59)
10.32 (0.49)
11+ years
Objective 1b: Measuring Pre/Post NTC Change Significant increase in PTSS scores (PCL-4) from pre- to post-training
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Figure 1. Data collection timeline
ISI
Post– Training
Simulated Deployment Training TST PCL-4 Exercise Demographics
ISI
Mean 24.95
SD 5.57
Years in the Military
4.54
5.11
Times Deployed
1.9
0.87
Age
Months Deployed Male
Number of Years in the Military 14
11.50
16.68
12
n 379
Percent 89.0%
10
* *
*
43
10.1%
1-10 years
276
64.6%
11 or more years
51
11.9%
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Rank E1-E4
n 244
Percent 62.1%
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E5-E6
86
21.9%
0
E7-E9
20
5.1%
Officers
43
10.9%
Objective 1a: Characterizing Sleep & PTSS Pre- Training Soldiers at E7-E9 reported the least amount of sleep duration Officers reported the most amount of hours sleeping Soldiers who served 11+ years reported the least amount of hours Soldiers who served 11+ years scored the highest on the PCL-4 Post- Training Soldiers at E7-E9 reported the least amount of sleep duration Officers reported the most amount of hours Soldiers who served 11+ years reported the least amount of hours Recently joined soldiers scored the highest on the PCL-4
Objective 2: Prediction of Disturbed Sleep on PTSS Insomnia Severity Index during pre-training was the most robust predictor of PTSS during post-training
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Recently Joined
One of the first of its kind to account for military-related factors when characterizing and predicting sleep and PTSS in Soldiers
Objective 1b: Measuring Pre/Post NTC Change Sleep duration remained similar from pre- to post-training No significant differences between ISI scores Significant increase in PTSS scores from pre- to post-training - Recently enlisted soldiers - Soldiers who have served 1-10 years in the military
TST PCL-4
PCL-4 scores
Pre-Training
National Training Center (NTC)
CONCLUSION
Sleep is a potential modifiable target for future research aimed at enhancing military readiness and resilience
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Recently Joined
1-10 years Pre-Training
Post-Training
11 or more years
Material has been reviewed by the Walter Reed Army Institute of Research. There is no objection to its presentation and/or publication. The opinions or assertions contained herein are the private views of the author, and are not to be construed as official, or as reflecting true views of the Department of the Army or the Department of Defense.* The investigators have adhered to the policies for protection of human subjects as prescribed in AR 70–25. For inquiries, please contact Ashlee McKeon, PhD, Walter Reed Army Institute of Research at
[email protected].
