The effect of mTBI and PTSD symptoms on computerized cognitive performance: Results from a sample of treatment-seeking active duty US service members.

TBI and PTSD occur in a significant number of service members and can each result in considerable distress and cognitive challenges. Past research has established the individual impact of mild TBI (mTBI) and PTSD on cognitive performance; however, findings regarding the combined effects of mTBI and PTSD on cognitive performance are inconsistent. The present study examined the potentially synergistic effects of mTBI and PTSD symptoms on cognitive performance in a sample of 180 treatment-seeking active duty service members. As part of a larger clinical study, participants completed several self-report measures and an objective cognitive assessment via computer-based testing. Compared to norms, service members with mTBI-only, PTSD-symptoms-only, and comorbid TBI and PTSD performed significantly worse on cognitive tests, and there was a significant effect of group on cognitive performance, even when controlling for performance validity. Notably, individuals experiencing both mTBI and PTSD performed worse than those with either condition alone; service members with mTBI-only and those with PTSD symptoms-only did not differ. Findings further illustrate the complexity of the relationship between these two conditions, indicating comorbid mTBI and PTSD may represent a unique challenge to cognitive performance. Additional research is needed to clarify their combined impact on post-injury functioning.

A Novel Intervention Platform for Service Members With Subjective Cognitive Complaints: Implementation, Patient Participation, and Satisfaction.

INTRODUCTION: Program overview of a novel cognitive training platform at Walter Reed National Military Medical Center (WRNMMC) for service members with subjective cognitive complaints: analysis of patient participation, satisfaction with the program, and perceived areas of improvement. MATERIALS AND METHOD: Retrospective review of 1,030 participants from November 2008 through May 2017. Data were obtained within an approved protocol (WRNMMC-EDO-2017-0004/# 876230). RESULTS: The program has shown growth in numbers of referrals, types of patient populations served, and patient visits. Patients report satisfaction with the program and endorse improvements in cognitive functions. CONCLUSIONS: This program model may benefit other military facilities looking to provide and assess novel therapeutic approaches.

Pyridostigmine, diethyltoluamide, permethrin, and stress: a double-blind, randomized, placebo-controlled trial to assess safety.

OBJECTIVE: To determine whether short-term human exposure to pyridostigmine bromide, diethyltoluamide, and permethrin, at rest or under stress, adversely affects short-term physical or neurocognitive performance. PARTICIPANTS AND METHODS: A multicenter, prospective, double-blind, placebo-controlled crossover trial exposing 64 volunteers to permethrin-impregnated uniforms, diethyltoluamide-containing skin cream, oral pyridostigmine, and corresponding placebos was performed. Each participant had 4 separate sessions, ensuring exposure to all treatments and placebos under both stress and rest conditions in random order. Outcomes Included physical performance (handgrip strength and duration, stair climbing, and pull-ups [males] or push-ups [females]), neurocognitive performance (computerized tests), and self-reported adverse effects. RESULTS: Permethrin was undetectable in the serum of all participants; pyridostigmine levels were higher Immediately after stress (41.6 ng/mL; 95% confidence Interval, 35.1-48.1 ng/mL) than rest (23.0 ng/mL; 95% confidence Interval, 19.2-26.9 ng/mL), whereas diethyltoluamide levels did not significantly differ by stress condition. Heart rate and systolic blood pressure increased significantly with stress compared with rest but did not vary with treatment vs placebo. Physical and neurocognitive outcome measures and self-reported adverse effects did not significantly differ by exposure group. CONCLUSION: Combined, correct use of pyridostigmine, diethyltoluamide, and permethrin is well tolerated and without evidence of short-term physical or neurocognitive impairment.

Initial evaluation of N,N-diethyl-m-toluamide and permethrin absorption in human volunteers under stress conditions.

OBJECTIVES: This was a pilot study to determine (1) whether it is feasible to effectively blind human subjects to the presence of the insect repellents N,N-diethyl-m-toluamide (DEET) and permethrin; (2) whether DEET affects the absorption of permethrin; and (3) whether combat videotape viewing and mental arithmetic are stressful. METHODS: Ten volunteers were exposed to DEET, permethrin, and stress (1-hour combat videotape plus mental arithmetic) in a double-blind, randomized, placebo-controlled trial. Outcome measurements included hemodynamics, plasma DEET and permethrin levels, and questionnaires to assess blinding. RESULTS: Highly sensitive serologic assays readily detected DEET but not permethrin. Staff members and subjects were effectively blinded to both. The videotape-math combination was stressful by both self-report and hemodynamic measures. CONCLUSIONS: It is possible to blind subjects with respect to DEET and permethrin. Permethrin on clothing does not enter the bloodstream at appreciable levels. Combat videotapes and mental arithmetic can be stressful.