Complicated versus uncomplicated mild traumatic brain injuries: A comparison of psychological, cognitive, and post-concussion symptom outcomes

Longitudinal Associations Between Persistent Post-Concussion Symptoms and Blood Biomarkers of Inflammation and CNS-Injury After Mild Traumatic Brain Injury

The aim of our study was to investigate the biological underpinnings of persistent post-concussion symptoms (PPCS) at 3 months following mild traumatic brain injury (mTBI). Patients (n = 192, age 16-60 years) with mTBI, defined as Glasgow Coma Scale (GCS) score between 13 and 15, loss of consciousness (LOC) <30 min, and post-traumatic amnesia (PTA) <24 h were included. Blood samples were collected at admission (within 72 h), 2 weeks, and 3 months. Concentrations of blood biomarkers associated with central nervous system (CNS) damage (glial fibrillary acidic protein [GFAP], neurofilament light [NFL], and tau) and inflammation (interferon gamma [IFNγ], interleukin [IL]-8, eotaxin, macrophage inflammatory protein-1-beta [MIP]-1β, monocyte chemoattractant protein [MCP]-1, interferon-gamma-inducible protein [IP]-10, IL-17A, IL-9, tumor necrosis factor [TNF], basic fibroblast growth factor [FGF]-basic platelet-derived growth factor [PDGF], and IL-1 receptor antagonist [IL-1ra]) were obtained. Demographic and injury-related factors investigated were age, sex, GCS score, LOC, PTA duration, traumatic intracranial finding on magnetic resonance imaging (MRI; within 72 h), and extracranial injuries. Delta values, that is, time-point differences in biomarker concentrations between 2 weeks minus admission and 3 months minus admission, were also calculated. PPCS was assessed with the British Columbia Post-Concussion Symptom Inventory (BC-PSI). In single variable analyses, longer PTA duration and a higher proportion of intracranial findings on MRI were found in the PPCS group, but no single biomarker differentiated those with PPCS from those without. In multi-variable models, female sex, longer PTA duration, MRI findings, and lower GCS scores were associated with increased risk of PPCS. Inflammation markers, but not GFAP, NFL, or tau, were associated with PPCS. At admission, higher concentrations of IL-8 and IL-9 and lower concentrations of TNF, IL-17a, and MCP-1 were associated with greater likelihood of PPCS; at 2 weeks, higher IL-8 and lower IFNγ were associated with PPCS; at 3 months, higher PDGF was associated with PPCS. Higher delta values of PDGF, IL-17A, and FGF-basic at 2 weeks compared with admission, MCP-1 at 3 months compared with admission, and TNF at 2 weeks and 3 months compared with admission were associated with greater likelihood of PPCS. Higher IL-9 delta values at both time-point comparisons were negatively associated with PPCS. Discriminability of individual CNS-injury and inflammation biomarkers for PPCS was around chance level, whereas the optimal combination of biomarkers yielded areas under the curve (AUCs) between 0.62 and 0.73. We demonstrate a role of biological factors on PPCS, including both positive and negative effects of inflammation biomarkers that differed based on sampling time-point after mTBI. PPCS was associated more with acute inflammatory processes, rather than ongoing inflammation or CNS-injury biomarkers. However, the modest discriminative ability of the models suggests other factors are more important in the development of PPCS.

Stressful life events are associated with self-reported fatigue and depressive symptoms in patients with mild traumatic brain injury

OBJECTIVE

To examine the associations between recent stressful life events and self-reported fatigue and depressive symptoms in patients with mild traumatic brain injury.

DESIGN

Observational cohort study.

PARTICIPANTS

Patients (aged 18-68 years) with mild traumatic brain injury (n = 99) or lower extremity orthopaedic injury (n = 34).

METHODS

Data on stressful life events and self-reported symptoms were collected 3 months post-injury. Stressful life events in the last 12 months were assessed as part of a structured interview using a checklist of 11 common life events, self-reported fatigue with Barrow Neurological Institute Fatigue Scale, and depressive symptoms with Beck Depression Inventory - Fast Screen.

RESULTS

Median number of stressful life events was 1 (range 0-7) in the mild traumatic brain injury group and 1.5 (range 0-6) in the orthopaedic injury group. The groups did not differ significantly in terms of fatigue or depressive symptoms. In the mild traumatic brain injury group, the total number of recent stressful life events correlated significantly with self-reported fatigue (rs = 0.270, p = 0.007) and depressive symptoms (rs = 0.271, p = 0.007).

CONCLUSION

Stressful life events are associated with self-reported fatigue and depressive symptoms in patients with mild traumatic brain injury. Clinicians should consider stressful life events when managing patients who experience these symptoms, as this may help identifying potential targets for intervention.

Screening for Anxiety and Depression Symptoms Using Concussion Symptom Scales Among Varsity Athletes

OBJECTIVE

This study examined associations between Sport Concussion Assessment Tool-5 (SCAT-5) symptom reporting and gold-standard measures of anxiety and depression, and explored the utility SCAT-5 symptom subscales to identify anxiety and depression symptomology.

DESIGN

Prospective cross-sectional study.

SETTING

York University in Toronto, Canada.

PARTICIPANTS

Preseason data were collected for varsity athletes (N = 296) aged between 17 and 25 years ( M = 20.01 years, SD = 1.69 years; 52% male).

MAIN OUTCOME MEASURES

The SCAT-5 symptom evaluation scale was used to assess baseline symptoms. The Generalized Anxiety Disorder Index-7 (GAD-7) and Patient Health Questionnaire-9 (PHQ-9) were used to assess symptoms of anxiety and depression, respectively.

RESULTS

Endorsement of SCAT-5 symptoms of feeling anxious, sadness, irritability, and feeling more emotional had the strongest correlations with the GAD-7 ( r' s > 0.400; P' s < 0.001). Sadness, trouble falling asleep, concentration problems, feeling slowed down, anxious, irritability, mental fog, fatigue, and memory problems had the highest correlations with the PHQ-9 ( r' s >0 .400; P' s < 0.001). The Emotional subscale from the SCAT-5 predicted mild to severe anxiety on the GAD-7 ( P < 0.001). The Sleep, Cognitive, and Emotional subscales predicted mild to severe depression on the PHQ-9 ( P' s < 0.05).

CONCLUSIONS

These findings provide better delineation of symptoms endorsed on the SCAT-5 symptoms that aid in identification of athletes with symptoms of anxiety or depression who may be at risk for developing a clinical disorder or experiencing persistent symptoms after a concussion.

Network analysis applied to post-concussion symptoms in two mild traumatic brain injury samples

Objective

A latent disease explanation cannot exclusively explain post-concussion symptoms after mild traumatic brain injury (mTBI). Network analysis offers an alternative form of explanation for relationships between symptoms. The study aimed to apply network analysis to post-concussion symptoms in two different mTBI cohorts; an acute treatment-seeking sample and a sample 10 years post-mTBI.

Method

The treatment-seeking sample (n = 258) were on average 6 weeks post-injury; the 10 year post mTBI sample (n = 193) was derived from a population-based incidence and outcomes study (BIONIC). Network analysis was completed on post-concussion symptoms measured using the Rivermead Post-Concussion Questionnaire.

Results

In the treatment-seeking sample, frustration, blurred vision, and concentration difficulties were central to the network. These symptoms remained central in the 10 year post mTBI sample. A Network Comparison Test revealed evidence of a difference in network structure across the two samples (p = 0.045). However, the only symptoms that showed significant differences in strength centrality across samples were irritability and restlessness.

Conclusion

The current findings suggest that frustration, blurred vision and concentration difficulties may have an influential role in the experience and maintenance of post-concussion symptoms. The impact of these symptoms may remain stable over time. Targeting and prioritising the management of these symptoms may be beneficial for mTBI rehabilitation.

Concussion and Psychological Effects: A Review of Recent Literature

ABSTRACT

The aim of this article is to provide an up-to-date review of psychological changes in association with postconcussive athletes. In particular, this article focused on the symptomatology, risk factors, and treatment of psychiatric diagnoses in patients who suffered a sports-related concussion (SRC). After an extensive review of prior and current literature, there is significant evidence that demonstrates an association of changes in mood and behavior, including new or worsening symptoms of anxiety, depression, and difficulty with attention and concentration in those who are recovering from a concussion. The goal of care in these patients is to identify and treat these psychological symptoms early to have more favorable long-term outcomes. Primary treatment should focus on psychotherapy; however, other considerations may be warranted in certain cases, such as selective serotonin reuptake inhibitors for depression and tricyclic antidepressants and gabapentin for short-term cognitive symptom improvement.

Return to work after mild traumatic brain injury: association with positive CT and MRI findings

Background

Return to work (RTW) might be delayed in patients with complicated mild traumatic brain injury (MTBI), i.e., MTBI patients with associated traumatic intracranial lesions. However, the effect of different types of lesions on RTW has not studied before. We investigated whether traumatic intracranial lesions detected by CT and MRI are associated with return to work and post-concussion symptoms in patients with MTBI.

Methods

We prospectively followed up 113 adult patients with MTBI that underwent a brain MRI within 3–17 days after injury. Return to work was assessed with one-day accuracy up to one year after injury. Rivermead Post-Concussion Symptoms Questionnaire (RPQ) and Glasgow Outcome Scale Extended (GOS-E) were conducted one month after injury. A Kaplan–Meier log-rank analysis was performed to analyze the differences in RTW.

Results

Full RTW-% one year after injury was 98%. There were 38 patients with complicated MTBI, who had delayed median RTW compared to uncomplicated MTBI group (17 vs. 6 days), and more post-concussion symptoms (median RPQ 12.0 vs. 6.5). Further, RTW was more delayed in patients with multiple types of traumatic intracranial lesions visible in MRI (31 days, n = 19) and when lesions were detected in the primary CT (31 days, n = 24). There were no significant differences in GOS-E.

Conclusions

The imaging results that were most clearly associated with delayed RTW were positive primary CT and multiple types of lesions in MRI. RTW-% of patients with MTBI was excellent and a single intracranial lesion does not seem to be a predictive factor of disability to work.

Pre-Injury headache and post-traumatic headache in patients with mild traumatic brain injury: neuropsychological, psychiatric, and post-concussion symptom outcomes

PRIMARY OBJECTIVE

Headache, both before and after injury, has been associated with worse outcome following mild traumatic brain injury (MTBI). This study examined whether three MTBI patient groups - no headache (reported no pre-/post-injury headache), pre-injury headache (reported pre-injury headache, nearly all of whom also reported post-injury headache), and post-traumatic headache only (denied pre-injury headache and reported post-injury headache) - differed in acute-to-subacute outcomes.

RESEARCH DESIGN

Cross-sectional observational study.

METHODS AND PROCEDURES

Patients within 21 days of a MTBI (n = 291) completed neuropsychological tests and questionnaires evaluating depression, anxiety, and post-concussion symptoms.

MAIN OUTCOMES AND RESULTS

Neuropsychological test performances did not differ between headache groups. Participants with pre-injury headache and participants with post-traumatic headache only reported greater change in self-reported physical and cognitive symptoms than participants with no headache. Participants with pre-injury headache reported worse post-injury anxiety symptoms than participants with post-traumatic headache only.

CONCLUSIONS

The pre-injury headache and post-traumatic headache only groups did not meaningfully differ in outcome within 21 days of MTBI, but they had worse physical and cognitive symptoms than participants with no headache. Future research should assess whether differences in outcome emerge further from injury and whether specific headache subtypes are differentially associated with outcome.

Vestibular-autonomic interactions: beyond orthostatic dizziness

PURPOSE OF REVIEW

This review aims to summarize the current literature describing vestibular-autonomic interactions and to describe their putative role in various disorders' clinical presentations, including orthostatic dizziness and motion sensitivity.

RECENT FINDINGS

The vestibular-autonomic reflexes have long been described as they relate to cardiovascular and respiratory function. Although orthostatic dizziness may be in part related to impaired vestibulo-sympathetic reflex (orthostatic hypotension), there are various conditions that may present similarly. A recent clinical classification aims to improve identification of individuals with hemodynamic orthostatic dizziness so that appropriate recommendations and management can be efficiently addressed. Researchers continue to improve understanding of the underlying vestibular-autonomic reflexes with recent studies noting the insular cortex as a cortical site for vestibular sensation and autonomic integration and modulation. Work has further expanded our understanding of the clinical presentation of abnormal vestibular-autonomic interactions that may occur in various conditions, such as aging, peripheral vestibular hypofunction, traumatic brain injury, and motion sensitivity.

SUMMARY

The vestibular-autonomic reflexes affect various sympathetic and parasympathetic functions. Understanding these relationships will provide improved identification of underlying etiology and drive improved patient management.

White matter microstructure of the neural emotion regulation circuitry in mild traumatic brain injury

Emotion regulation is related to recovery after mild traumatic brain injury (mTBI). This longitudinal tractography study examined white matter tracts subserving emotion regulation across the spectrum of mTBI, with a focus on persistent symptoms. Four groups were examined: (a) symptomatic (n = 33) and (b) asymptomatic (n = 20) patients with uncomplicated mTBI (i.e., no lesions on computed tomography [CT]), (c) patients with CT-lesions in the frontal areas (n = 14), and (d) healthy controls (HC) (n = 20). Diffusion and conventional MRI were performed approximately 1- and 3-months post-injury. Whole-brain deterministic tractography followed by region of interest analyses was used to identify forceps minor (FM), uncinate fasciculus (UF), and cingulum bundle as tracts of interest. An adjusted version of the ExploreDTI Atlas Based Tractography method was used to obtain reliable tracts for every subject. Mean fractional anisotropy (FA), mean, radial and axial diffusivity (MD, RD, AD), and number of streamlines were studied per tract. Linear mixed models showed lower FA, and higher MD, and RD of the right UF in asymptomatic patients with uncomplicated mTBI relative to symptomatic patients and HC. Diffusion alterations were most pronounced in the group with frontal lesions on CT, particularly in the FM and UF; these effects increased over time. Within the group of patients with uncomplicated mTBI, there were no associations of diffusion measures with the number of symptoms nor with lesions on conventional MRI. In conclusion, mTBI can cause microstructural changes in emotion regulation tracts, however, no explanation was found for the presence of symptoms.