Excessive daytime sleepiness is associated with altered gene expression in military personnel and veterans with posttraumatic stress disorder: an RNA sequencing study

Persistent hypersomnia following repetitive mild experimental traumatic brain injury: Roles of chronic stress and sex differences

Traumatic brain injury (TBI) is often more complicated than a single head injury. An extreme example of this point may be military service members who experience a spectrum of exposures over a prolonged period under stressful conditions. Understanding the effects of complex exposures can inform evaluation and care to prevent persistent symptoms. We designed a longitudinal series of non-invasive procedures in adult mice to evaluate the effects of prolonged mild stress and head injury exposures. We assessed anxiety, depression, and sleep-wake dysfunction as symptoms that impact long-term outcomes after mild TBI. Unpredictable chronic mild stress (UCMS) was generated from a varied sequence of environmental stressors distributed within each of 21 days. Subsequently, mice received a mild blast combined with closed-head mild TBI on 5 days at 24-h intervals. In males and females, UCMS induced anxiety without depressive behavior. A major finding was reproducible sleep-wake dysfunction through 6- to 12-month time points in male mice that received UCMS with repetitive blast plus TBI events, or surprisingly after just UCMS alone. Specifically, male mice exhibited hypersomnia with increased sleep during the active/dark phase and fragmentation of longer wake bouts. Sleep-wake dysfunction was not found with TBI events alone, and hypersomnia was not found in females under any conditions. These results identify prolonged stress and sex differences as important considerations for sleep-wake dysfunction. Furthermore, this reproducible hypersomnia with impaired wakefulness is similar to the excessive daytime sleepiness reported in patients, including patients with TBI, which warrants further clinical screening, care, and treatment development.

Residual sleepiness in veterans with post-traumatic stress disorder and obstructive sleep apnea

PURPOSE

The causes of residual excessive sleepiness (RES) in patients with post-traumatic stress disorder (PTSD) and obstructive sleep apnea (OSA) are multifactorial and modulated by comorbid conditions. The aim of the present study was to elucidate clinical and polysomnographic determinants of RES in continuous positive airway pressure (CPAP)-adherent OSA veterans with PTSD.

METHODS

The study protocol consisted of a retrospective analysis of consecutive cases of patients with PTSD who presented to the Veterans Affairs sleep clinics with adequately treated OSA between June 1, 2017 and October 15, 2021. Based on the Epworth Sleepiness Scale (ESS), patients were categorized into RES (ESS ≥ 11) and no RES (ESS < 11) groups. Demographic and PSG data were subjected to univariate and multivariate analyses to ascertain predictive factors of RES.

RESULTS

Out of 171 veterans with PTSD who were adherent to CPAP, 59 (35%) continued to experience RES. The RES group had a decrease in mean ESS score of 1.2 ± 4.5 after CPAP treatment compared with 4.6 ± 4.9 for the no RES group (< 0.001). A dose-response was observed between CPAP use and RES (p = 0.003). Multivariate regression analysis identified higher baseline ESS (OR 1.30; 95% CI 1.16-1.44), greater percentage of time spent in REM sleep (OR 0.91; 95% CI 0.85-0.96), CPAP use less than 6 h (OR 2.82; 95% CI 1.13-7.01), and a positive screen for depression (OR 1.69; 95% CI 1.03-4.72) as independent predictors of RES in patients with PTSD and OSA.

CONCLUSION

RES is highly prevalent in patients with PTSD and OSA despite adherence to CPAP and is independently associated with percentage time spent in REM, duration of CPAP utilization, and symptoms of depression.

Sleep disturbances following traumatic brain injury are associated with poor neurobehavioral outcomes in U.S. military service members and veterans

STUDY OBJECTIVES

This study examined whether sleep disturbances were associated with neurobehavioral outcome following a traumatic brain injury (TBI) in a well characterized group of service members and veterans.

METHODS

Six-hundred and six participants were enrolled into the Defense and Veterans Brain Injury Center, 15-Year Longitudinal TBI study. All participants completed a battery of tests measuring self-reported sleep disturbances, neurobehavioral symptoms, and Posttraumatic Stress Disorder PTSD symptoms. Data were analyzed using analysis of variance with post-hoc comparisons. Four groups were analyzed separately: uncomplicated mild TBI (MTBI); complicated mild, moderate, severe, or penetrating - combined TBI (CTBI); injured controls (IC, i.e., orthopedic or soft-tissue injury without TBI); and non-injured controls (NIC).

RESULTS

A higher proportion of the MTBI group reported moderate-severe sleep disturbances (66.5%) compared to the IC (54.9%), CTBI (47.5%), and NIC groups (34.3%). Participants classified as having Poor Sleep had significantly worse scores on the majority of TBI-QOL scales compared to those classified as having Good Sleep, regardless of TBI severity or the presence of TBI. There was a significant interaction between sleep disturbances and PTSD. While sleep disturbances and PTSD by themselves were significant factors associated with worse outcome, both factors combined resulted in worse outcome than either singularly.

CONCLUSIONS

Regardless of group (injured or NIC), sleep disturbances were common and were associated with significantly worse neurobehavioral functioning. When experienced concurrently with PTSD, sleep disturbances pose significant burden to service members and veterans.

The mediating role of daytime sleepiness between problematic smartphone use and post-traumatic symptoms in COVID-19 home-refined adolescents

Background

COVID-19 was first recognized in late 2019 in China, at which time school closures forced most students to isolate at home or maintain social distance, both of which increased smartphone use, daytime sleepiness and post traumatic disorder (PTSD) risks. However, to date, no research has fully explored these behavioral risks or the consequences.

Methods

Two thousand and ninety home-confined students from two Chinese high schools participated in an online-based questionnaire battery that assessed their sociodemographic characteristics, COVID-19 related exposures, daytime sleepiness, problematic smartphone use, and PTSD. The subsequent data were subjected to mediation analysis, and structural equation models (SEM) were employed to explore the variable relationships.

Results

The problematic smartphone use, daytime sleepiness and PTSD prevalence were respectively 16.4%, 20.2% and 6.9%. The number of COVID-19 related exposure was directly associated with problematic smartphone use and PTSD symptoms. Problematic smartphone use was found to be a mediator between COVID-19 related exposure and PTSD symptoms, and daytime sleepiness was found to partially mediate the associations between problematic smartphone use and PTSD.

Conclusions

The more exposure associated with the pandemic, the more psychological and behavioral problems the adolescents had. The relatively high rate of problematic smartphone use in home isolated adolescents possibly increased the risk of daytime sleepiness and psychological problems. Therefore, targeted improvements are needed to reduce the risk of psychological problems and daytime sleepiness in adolescents.