Sleep disturbance and cognition in people with TBI

VX-765 Alleviates Circadian Rhythm Disorder in a Rodent Model of Traumatic Brain Injury Plus Hemorrhagic Shock and Resuscitation

Severe traumatic brain injury (TBI) can result in persistent complications, including circadian rhythm disorder, that substantially affect not only the injured people, but also the mood and social interactions with the family and the community. Pyroptosis in GFAP-positive astrocytes plays a vital role in inflammatory changes post-TBI. We determined whether VX-765, a low molecular weight caspase-1 inhibitor, has potential therapeutic value against astrocytic inflammation and pyroptosis in a rodent model of TBI plus hemorrhagic shock and resuscitation (HSR). A weight-drop plus bleeding and refusion model was used to establish traumatic exposure in rats. VX-765 (50 mg/kg) was injected via the femoral vein after resuscitation. Wheel-running activity was assessed, brain magnetic resonance images were evaluated, the expression of pyroptosis-associated molecules including cleaved caspase-1, gasdermin D (GSDMD), and interleukin-18 (IL-18) in astrocytes in the region of anterior hypothalamus, were explored 30 days post-trauma. VX-765-treated rats had significant improvement in circadian rhythm disorder, decreased mean diffusivity (MD) and mean kurtosis (MK), increased fractional anisotropy (FA), an elevated number and branches of astrocytes, and lower cleaved caspase-1, GSDMD, and IL-18 expression in astrocytes than TBI + HSR-treated rats. These results demonstrated that inhibition of pyroptosis-associated astrocytic activations in the anterior hypothalamus using VX-765 may ameliorate circadian rhythm disorder after trauma. In conclusion, we suggest that interventions targeting caspase-1-induced astrocytic pyroptosis by VX-765 are promising strategies to alleviate circadian rhythm disorder post-TBI.

Agitation after traumatic brain injury: a review of current and future concepts in diagnosis and management

OBJECTIVES

Agitation and aggression are common following traumatic brain injury. The challenges related to these disorders affect all stages of recovery, from the acute hospital to the community setting. The aim of this literature review is to provide an updated overview of the current state of post-traumatic agitation research.

METHODS

We performed a PubMed literature review which included recent confirmatory and novel research as well as classic and historical studies to integrate past and future concepts.

RESULTS

Areas explored include the personal and societal effects of post-traumatic agitation, methods for defining and diagnosing several neurobehavioral disorders, and pathophysiology and management of agitation and aggression. Target areas for future study are identified and discussed.

DISCUSSION

While much progress has been made in understanding post-traumatic agitation, there remain several key areas that require further elucidation to support the care and treatment for people with traumatic brain injury.

Aging with TBI vs. Aging: 6-month temporal profiles for neuropathology and astrocyte activation converge in behaviorally relevant thalamocortical circuitry of male and female rats

Traumatic brain injury (TBI) manifests late-onset and persisting clinical symptoms with implications for sex differences and increased risk for the development of age-related neurodegenerative diseases. Few studies have evaluated chronic temporal profiles of neuronal and glial pathology that include sex as a biological variable. After experimental diffuse TBI, late-onset and persisting somatosensory hypersensitivity to whisker stimulation develops at one-month post-injury and persists to at least two months post-injury in male rats, providing an in vivo model to evaluate the temporal profile of pathology responsible for morbidity. Whisker somatosensation is dependent on signaling through the thalamocortical relays of the whisker barrel circuit made up of glutamatergic projections between the ventral posteromedial nucleus of the thalamus (VPM) and primary somatosensory barrel cortex (S1BF) with inhibitory (GABA) innervation from the thalamic reticular nucleus (TRN) to the VPM. To evaluate the temporal profiles of pathology, male and female Sprague Dawley rats ( n = 5-6/group) were subjected to sham surgery or midline fluid percussion injury (FPI). At 7-, 56-, and 168-days post-injury (DPI), brains were processed for amino-cupric silver stain and glial fibrillary acidic protein (GFAP) immunoreactivity, where pixel density of staining was quantified to determine the temporal profile of neuropathology and astrocyte activation in the VPM, S1BF, and TRN. FPI induced significant neuropathology in all brain regions at 7 DPI. At 168 DPI, neuropathology remained significantly elevated in the VPM and TRN, but returned to sham levels in the S1BF. GFAP immunoreactivity was increased as a function of FPI and DPI, with an FPI × DPI interaction in all regions and an FPI × Sex interaction in the S1BF. The interactions were driven by increased GFAP immunoreactivity in shams over time in the VPM and TRN. In the S1BF, GFAP immunoreactivity increased at 7 DPI and declined to age-matched sham levels by 168 DPI, while GFAP immunoreactivity in shams significantly increased between 7 and 168 days. The FPI × Sex interaction was driven by an overall greater level of GFAP immunoreactivity in FPI males compared to FPI females. Increased GFAP immunoreactivity was associated with an increased number of GFAP-positive soma, predominantly at 7 DPI. Overall, these findings indicate that FPI, time post-injury, sex, region, and aging with injury differentially contribute to chronic changes in neuronal pathology and astrocyte activation after diffuse brain injury. Thus, our results highlight distinct patterns of pathological alterations associated with the development and persistence of morbidity that supports chronic neuropathology, especially within the thalamus. Further, data indicate a convergence between TBI-induced and age-related pathology where further investigation may reveal a role for divergent astrocytic phenotypes associated with increased risk for neurodegenerative diseases.

A short add-on sleep intervention in the rehabilitation of individuals with acquired brain injury: A randomized controlled trial

BACKGROUND

Sleep disturbances are common after acquired brain injury (ABI) and have a negative impact on functioning.

OBJECTIVE

This study examines whether a short add-on therapy for sleep disturbances in individuals with ABI is effective in addition to rehabilitation treatment as usual.

METHODS

In the randomized-controlled study, 54 adults with ABI and self-reported sleep disturbances receiving outpatient rehabilitation services were randomized in two groups: one receiving a sleep intervention (based on cognitive behavioural therapy for insomnia (CBT-I)) in addition to their rehabilitation treatment (CBT-I + TAU group) and one receiving treatment as usual (TAU). The primary outcome was sleep quality, measured with the Pittsburgh Sleep Quality Index (PSQI). Secondary outcomes included measures of anxiety, depression, fatigue and dysfunctional beliefs and attitudes about sleep.

RESULTS

The short add-on sleep therapy resulted in improvements in sleep quality in the CBT-I + TAU group as compared to the TAU group (ES = 0.924). Furthermore, the CBT-I + TAU group reported less dysfunctional beliefs and attitudes about sleep and were better able to cope with fatigue compared to the TAU group.

CONCLUSIONS

The application of this short add-on sleep intervention could be implemented in neuropsychological rehabilitation settings.

Gaze stability in young adults with previous concussion history

BACKGROUND

Disruption of visual-vestibular interaction after concussion can cause gaze instability with head movements. The long-term impact of concussion on gaze stability is unknown.

OBJECTIVE

This cross-sectional comparative pilot study examined gaze stability in the chronic stage after concussion (greater than one year). A secondary objective was to examine the relationship between gaze stability and sleep.

METHODS

Outcome measures included: 1. Gaze stability in logMAR (mean loss of dynamic visual acuity (DVA) in the yaw and pitch planes); 2. Pittsburgh Sleep Quality Index (PSQI); 3. Epworth Sleepiness Scale (ESS). Post-Concussion Symptom Scale (PCSS), time since injury, and number of concussions were collected for the people with concussion.

RESULTS

The study sample included thirty-four adults (mean age 23.35±1.3 years). Seventeen had a history of 1-9 concussions, with a mean duration of 4.4±1.9 years since last concussion; and 17 were age and sex-matched controls. Mean pitch plane DVA loss was greater in the concussion group compared to the control group (p = 0.04). Participants with previous concussion had lower sleep quality based on the PSQI (p = 0.01) and increased daytime sleepiness based on the ESS (p = 0.01) compared to healthy controls. Mean DVA loss in the pitch plane was significantly correlated with the PSQI (r = 0.43, p = 0.01) and the ESS (r = 0.41, p = 0.02).

CONCLUSION

Significant differences in dynamic visual acuity may be found in young adults long after a concussion, compared with those who have no concussion history. Furthermore, loss of dynamic visual acuity was associated with poorer sleep quality and higher daytime sleepiness.

The impact of a yoga-based physical therapy group for individuals with traumatic brain injury: results from a pilot study

OBJECTIVE

To compare the impacts of yoga-based physical therapy versus a seated rest within the context of standard rehabilitation practice on sleep, heart rate variability (HRV), anxiety, and fatigue during acute traumatic brain injury (TBI) rehabilitation.

METHODS

Eleven individuals participated in this crossover study involving the following interventions in a randomized order: group yoga-based physical therapy (YPT), conventional physical therapy (CPT), and group seated rest in a relaxing environment (SR). HRV and self-reported anxiety and fatigue were measured immediately before and after each group, and sleep after each condition and at baseline. Data was analyzed using generalized linear mixed models with repeated measures.

RESULTS

The interaction between time and treatment was statistically significant (p = .0203). For the SR treatment, wake after sleep onset (WASO) rate was reduced from 14.99 to 10.60 (IRR = 0.71; p = .006). Time and treatment were not found to be statistically significantly associated with any of the secondary outcomes.

CONCLUSION

Yoga-based physical therapy is feasible and safe in the inpatient rehabilitation setting following TBI. Sleep quality improved following the addition of a one-hour seated rest in a relaxing environment to a standard rehabilitation daily schedule, suggesting that structured rest time may be beneficial to sleep hygiene during inpatient rehabilitation following TBI. ClinicalTrials.Gov Registration Number: NCT03701594.