Warfighter Resilience

PURPOSE

Our aim in this study was to psychometrically test resilience assessments (Ego Resiliency Scale [ER89], Connor-Davidson Resilience Scale [CD-RISC 25], Responses to Stressful Experiences Scale [RSES short-form]) and describe resilience levels in a Special Operations Forces (SOF) combat sample.

METHODS

Fifty-eight SOF combat Servicemembers either entering SOF (career start; n = 38) or having served multiple years with their SOF organization (mid-career; n = 20) self-reported resilience, mild traumatic brain injury (mTBI) history, and total military service.

RESULTS

All resilience metrics demonstrated acceptable internal consistency, but ceiling effects were found for CD-RISC and RSES scores. ER89 scores were moderate on average. ER89 scores were higher in SOF career start than mid-career Servicemembers (ηρ2 = 0.07) when accounting for the interaction between SOF career stage and total military service (ηρ2 = 0.07).

DISCUSSION

SOF mid-career Servicemembers had similar ER89 resilience scores with more total military service. The SOF career start combat Servicemembers had higher ER89 measured resilience with less total military service only, potentially showing a protective effect of greater service before entering SOF.

CONCLUSION

The ER89 may be a more optimal military resilience metric than the other metrics studied; longitudinal research on SOF combat Servicemember resilience is warranted.

Relationship between Anterior Pituitary Volume and IGF-1 Serum Levels in Soldiers with Mild Traumatic Brain Injury History

PURPOSE

A high mild traumatic brain injury (mTBI) incidence rate exists in military and sport. Hypopituitarism is an mTBI sequela; however, few studies have examined this phenomenon in those with an mTBI history. This cross-sectional study of Special Operations Forces combat soldiers aimed 1) to relate anterior pituitary gland volumes (actual and normalized) to insulin-like growth factor 1 (IGF-1) concentrations, 2) to examine the effect of mTBI history on anterior pituitary gland volumes (actual and normalized) and IGF-1 concentrations, and 3) to measure the odds of demonstrating lower anterior pituitary gland volumes (actual and normalized) or IGF-1 concentrations if self-reporting mTBI history.

METHODS

Anterior pituitary gland volumes were manually segmented from T1-weighted 3D brain MRI sequences; IGF-1 serum concentrations were quantified using commercial enzyme-linked immunosorbent assays. Correlations and linear regression were used to determine the association between IGF-1 serum concentration and anterior pituitary gland volume (n = 74). Independent samples t-tests were used to compare outcomes between mTBI groups and logistic regression models were fit to test the odds of demonstrating IGF-1 concentration or anterior pituitary volume less than sample median based on mTBI group (n = 54).

RESULTS

A significant linear relationship between the subjects' anterior pituitary gland volumes and IGF-1 concentrations (r72 = 0.35, P = 0.002) was observed. Soldiers with mTBI history had lower IGF-1 concentrations (P < 0.001) and lower anterior pituitary gland volumes (P = 0.037) and were at greater odds for IGF-1 serum concentrations less than the sample median (odds ratio = 5.73; 95% confidence interval = 1.77-18.55).

CONCLUSIONS

Anterior pituitary gland volume was associated with IGF-1 serum concentrations. Mild TBI history may be adversely associated with anterior pituitary gland volumes and IGF-1 concentrations. Longitudinal IGF-1 and anterior pituitary gland monitoring may be indicated in those who report one or more mTBI.

Active Warfighter Mental Health Lower in Mid-Career

PURPOSE

The present study investigated Special Operations Forces (SOF) combat Servicemember mental health at different SOF career stages in association with resilience.

METHODS

Fifty-eight SOF combat Service Members either entering SOF (career start; n=38) or multiple years with their SOF organization (mid-career; n=20) self-reported mild traumatic brain injury (TBI) history, resilience, subjective well-being, depression, anxiety, and posttraumatic stress. Poisson regression analyses were employed to test SOF career stage differences in each mental health symptom using resilience, while accounting for other pertinent military factors.

RESULTS

There were significant interaction effects of SOF career stage and resilience on mental health symptoms. SOF career start combat Servicemembers endorsed lower depression and posttraumatic stress and higher subjective well-being with higher resilience, but these associations between resilience and mental health symptoms were not seen in SOF mid-career Servicemembers.

CONCLUSIONS

Although preliminary, the adaptive association between resilience and mental health seemed to be blunted in combat Servicemembers having served multiple years in SOF. This information informs research to provide evaluation tools to support prophylactic performance and long-term health preservation in military populations.

The relationship between resilience and neurophysiological stress in Special Operations Forces combat service members

Military resilience research is increasing due to the growing literature associating resilience with stress adaptation. This study aimed to investigate which physiological stress adaptation components were associated with resilience in Special Operations Forces combat service members. Special Operations Forces combat service members (n = 117) self-reported resilience (ER89) and lifetime clinician-confirmed mild traumatic brain injury history. Participants also underwent transcranial Doppler ultrasonography to measure middle cerebral artery velocity during rest and a breath-holding task. Neither resilience nor mild traumatic brain injury history was significantly associated with middle cerebral artery velocity percent increase following breath-holding; younger Special Operations Forces combat service members had a higher percent increase in middle cerebral artery velocity following a breath-holding task. Resilience was negatively associated with time to return to baseline middle cerebral artery velocity following peak velocity; whereas, mild traumatic brain injury history did not have a significant association. The Special Operations Forces combat service members that scored higher in resilience tended to return to baseline middle cerebral artery velocity following peak velocity faster than their less resilient counterparts. More resilient Special Operations Forces combat service members recovered faster from physiological stress (breath-holding) than less resilient counterparts. This is the first study to investigate resilience and cerebrovascular stress response and recovery in this population. Our initial findings indicated that the Ego Resiliency Scale may be an optimal resilience psychometric and should be used to evaluate effective military resilience trainings, which aim to improve performance and mental health.

The athletic preparticipation evaluation: cardiovascular assessment

Thousands of young athletes receive preparticipation evaluations each year in the United States. One objective of these evaluations is to detect underlying cardiovascular abnormalities that may predispose an athlete to sudden death. The leading cardiovascular causes of sudden death in young athletes include hypertrophic cardiomyopathy, congenital coronary artery anomalies, repolarization abnormalities, and Marfan syndrome. Because these abnormalities are rare and difficult to detect clinically, it is recommended that family physicians use standardized history questions and examination techniques. Athletes, accompanied by their parents, if possible, should be asked about family history of cardiac disease and sudden death; personal cardiac history; and exercise-related symptoms, specifically syncope, chest pain, and palpitations. The physical examination should include blood pressure measurement, palpation of radial and femoral pulses, dynamic cardiac auscultation, and evaluation for Marfan syndrome. Athletes with "red flag" signs or symptoms may need activity restriction, special testing, and referral if the diagnosis is unclear.