Multiple Past Concussions Are Associated with Ongoing Post-Concussive Symptoms but Not Cognitive Impairment in Active-Duty Army Soldiers

Abstract

The extent to which multiple past concussions are associated with lingering symptoms or mental health problems in military service members is not well understood. The purpose of this study was to examine the association between lifetime concussion history, cognitive functioning, general health, and psychological health in a large sample of fit-for-duty U.S. Army soldiers preparing for deployment. Data on 458 active-duty soldiers were collected and analyzed. A computerized cognitive screening battery (CNS-Vital Signs(®)) was used to assess complex attention (CA), reaction time (RT), processing speed (PS), cognitive flexibility (CF), and memory. Health questionnaires included the Neurobehavioral Symptom Inventory (NSI), PTSD Checklist-Military Version (PCL-M), Zung Depression and Anxiety Scales (ZDS; ZAS), Perceived Stress Scale (PSS), Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and the Alcohol Use and Dependency Identification Test (AUDIT). Soldiers with a history of multiple concussions (i.e., three or more concussions) had significantly greater post-concussive symptom scores compared with those with zero (d=1.83, large effect), one (d=0.64, medium effect), and two (d=0.64, medium effect) prior concussions. Although the group with three or more concussions also reported more traumatic stress symptoms, the results revealed that traumatic stress was a mediator between concussions and post-concussive symptom severity. There were no significant differences on neurocognitive testing between the number of concussions. These results add to the accumulating evidence suggesting that most individuals recover from one or two prior concussions, but there is a greater risk for ongoing symptoms if one exceeds this number of injuries.

Multiple Mild Traumatic Brain Injuries Are Associated with Increased Rates of Health Symptoms and Gulf War Illness in a Cohort of 1990–1991 Gulf War Veterans

“…Our health symptom findings coincide with Miller and colleagues [ 27 ] research, which demonstrated that active duty Soldiers with two or more head injuries (<3 months) reported more health symptoms. Alternatively, work from Dretsch and colleagues [ 28 ] in active duty Soldiers preparing for deployment found an association between three or more concussions and increased rates of post-concussive symptoms measured by the neurobehavioral symptom inventory, which coincides with our CMI and Kansas GWI criteria findings. However, Miller et al [ 27 ] only grouped Soldiers by no, one, or two or more mTBIs.…”

“…However, Miller et al [ 27 ] only grouped Soldiers by no, one, or two or more mTBIs. Therefore, it is possible that the Soldiers with three or more mTBIs were driving the higher rate of symptom endorsement, which would be more consistent with the work of Dretsch [ 28 ].…”

“…Furthermore, veterans reporting more than one mTBI had an increased risk of experiencing health symptoms, such as headaches and sleep disturbances, compared to those only reporting a single head injury [ 26 ]. Studies specifically addressing the effects of multiple head injuries in military populations have found higher rates of post-concussive symptoms and sleep disturbances in Soldiers reporting multiple TBIs [ 27 , 28 ].…”

Cross-Phenotype Polygenic Risk Score Analysis of Persistent Post-Concussive Symptoms in U.S. Army Soldiers with Deployment-Acquired Traumatic Brain Injury

“…2 Indeed, a subset of individuals can experience persistent physical, cognitive, and emotional post-concussive symptoms (PCS) after single or multiple TBI. 3,4 Numerous epidemiological studies have investigated prognostic factors and adverse consequences of persistent PCS. [5][6][7][8] Although there is still open discussion regarding the specificity of PCS consequent to TBI, 4,9 TBI and persistent PCS are associated with short-term sequelae, including emotional distress, difficulty in making a return to society, inability to return to work, and reduced quality of life, 10 and long-term events, including increased risk of Alzheimer's disease, Parkinson's disease, mild cognitive impairment, depression, and bipolar disorder.…”

Resilience and Traumatic Brain Injury Among Iraq/Afghanistan War Veterans: Differential Patterns of Adjustment and Quality of Life

“…Although several studies find that deployment‐related TBI is significantly associated with postconcussive symptoms, distress, and decreased health‐related quality of life (Brickell, Lange, & French, ; Dretsch, Silverberg, & Iverson, ; Vanderploeg et al., ), critical and meta‐analytic reviews of the literature (Broshek, De Marco, & Freeman, ; Panayioutou, Jackson, & Crowe, ) and longitudinal studies of predeployment characteristics (Lee, Garber, & Zamorski, ) indicate that a variety of psychological and contextual factors (e.g., litigation) account for much of the variance associated with chronic emotional and psychosocial problems reported post‐TBI. Consequently, research is needed to isolate the psychological characteristics associated with complicated adjustment among Veterans with deployment‐related TBI, preferably with variables that can inform assessment practices and psychological interventions.…”