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

Abstract

Recent research demonstrated a relation between traumatic brain injury (TBI), health symptoms and diagnosis of Gulf War Illness (GWI) in Gulf War Veterans, but no study has examined the impact of multiple mild TBIs (mTBIs). A total of 229 male Gulf War Veterans from the Ft Devens Cohort were categorized by a number of mTBIs reported. One-way ANOVA and chi-square test of independence were used to test for differences in total reported health symptoms and diagnosis of chronic multisymptom illness (CMI) or Kansas GWI criteria, two of the most common case definitions of GWI. A total of 72 veterans reported no mTBIs (31.4%), 26 reported one mTBI (11.4%), 25 reported two mTBIs (10.9%), and 106 veterans reported sustaining three or more mTBIs (46.3%). Veterans reporting two or more mTBIs (p < 0.01) or three or more mTBIs (p < 0.001) endorsed significantly higher rates of health symptoms than Veterans reporting no mTBIs. Significantly higher rates of CMI (p = 0.035) and Kansas GWI criteria (p < 0.001) were seen in the three or more mTBI group. Results suggest two mTBIs increase risk of health symptoms, but three mTBIs may be the threshold needed to sustain chronic symptom reporting needed for a formal diagnosis. These findings highlight the importance of implementing policies and procedures monitoring head injuries in military personnel.

The Multiple Hit Hypothesis for Gulf War Illness: Self-Reported Chemical/Biological Weapons Exposure and Mild Traumatic Brain Injury

“…Given the brevity of the GW ground war, mTBI has not been investigated as a primary factor of GWI until recently. In our recent work with the Ft. Devens Cohort, veterans with mTBI had increased rates of GWI as determined by Centers for Disease Control (CDC) and Kansas GWI criteria [ 16 , 17 ]. These studies also showed that the increased number of mTBIs was associated with higher number of total symptoms reported [ 16 ].…”

“…In our recent work with the Ft. Devens Cohort, veterans with mTBI had increased rates of GWI as determined by Centers for Disease Control (CDC) and Kansas GWI criteria [ 16 , 17 ]. These studies also showed that the increased number of mTBIs was associated with higher number of total symptoms reported [ 16 ]. However, the timing of the mTBI was not available for the Ft. Devens Cohort studies, leaving open the question of whether the proximity of the mTBI to CBW exposure had an impact on the rates of GWI and comorbid chronic health conditions.…”

“…Mild traumatic brain injury (mTBI) has been reported as another less intuitive potential factor in the development of chronic health symptoms experienced by GW veterans that can also affect CNS functioning [ 16 , 17 ]. Correspondingly, GW veterans with any history of mTBI in the large, longitudinally followed Ft. Devens cohort (FDC) have been found to have significantly higher rates of GWI (Kansas and CMI criteria) than those without mTBI [ 16 , 17 ]. In addition, the total number of health symptoms reported by the Ft. Devens cohort was positively correlated with total number of mTBIs.…”

Dizziness, Vertigo, and Mental Health Comorbidity in Gulf War Veterans

“…The investigation of dizziness/vertigo symptoms and vestibular dysfunction in Gulf War veterans is complicated by the presence of mental health comorbidities and traumatic brain injury (TBI). Gulf War veterans, and deployed veterans in general, experience higher rates of anxiety, posttraumatic stress disorder (PTSD), depression, and TBI (Black et al, 2004;Bierer et al, 2015;McKenzie et al, 2015;Yee et al, 2017) when compared with civilian and nondeployed military populations.…”

“…A recent series of studies has considered the impact of TBI on the presence of chronic multisymptom illness in Gulf War veterans, finding increased self-reported mild TBI is related to an increase in physical symptom burden (Yee et al, 2017). These authors suggested that the combined effects of head injury and exposures in Gulf War veterans may promote persistent neuroinflammation thought to be at the root of GWI symptoms (Yee et al, 2017). Mild TBI has also been shown to have a persistent negative influence on vertigo/dizziness symptoms in approximately one-third of individuals (Fife and Kalra, 2015).…”