Reference Values for the Rivermead Post-Concussion Symptoms Questionnaire (RPQ) from General Population Samples in the United Kingdom, Italy, and The Netherlands

mTBI Biological Biomarkers as Predictors of Postconcussion Syndrome-Review

Postconcussion syndrome (PCS) is one of the leading complications that may appear in patients after mild head trauma. Every day, thousands of people, regardless of age, gender, and race, are diagnosed in emergency departments due to head injuries. Traumatic Brain Injury (TBI) is a significant public health problem, impacting an estimated 1.5 million people in the United States and up to 69 million people worldwide each year, with 80% of these cases being mild. An analysis of the available research and a systematic review were conducted to search for a solution to predicting the occurrence of postconcussion syndrome. Particular biomarkers that can be examined upon admission to the emergency department after head injury were found as possible predictive factors of PCS development. Setting one unequivocal definition of PCS is still a challenge that causes inconsistent results. Neuron Specific Enolase (NSE), Glial Fibrillary Acidic Protein (GFAP), Ubiquitin C-terminal Hydrolase-L1 (UCH-L1), Serum Protein 100 B (s100B), and tau protein are found to be the best predictors of PCS development. The presence of all mentioned biomarkers is confirmed in severe TBI. All mentioned biomarkers are used as predictors of PCS. A combined examination of NSE, GFAP, UCH-1, S100B, and tau protein should be performed to detect mTBI and predict the development of PCS.

Serum neurofilament light chain, inflammatory markers, and kynurenine metabolites in patients with persistent post-concussion symptoms: A cohort study

BACKGROUND

Concussion leads to persistent post-concussion symptoms (PPCS) in up to one-third of those affected. While previous research has linked the initial trauma to elevated serum levels of neurofilament light chain (NFL), inflammatory markers, and neurotoxic metabolites within the kynurenine pathway, few studies have explored their relevance in PPCS. This study aims to investigate these biomarkers in PPCS patients, elucidating their relevance in the prolonged phase of concussion.

METHODS

Serum samples from 86 PPCS individuals aged 18-30 years, 2-6 months post-trauma were analyzed, with 54 providing follow-up samples after seven months. NFL was measured using single-molecule array (Simoa) technology, 13 inflammatory markers via a Luminex immunoassay, and five kynurenine metabolites using liquid chromatography-mass spectrometry. A control group of 120 healthy anonymous blood donors was recruited for comparison.

RESULTS

No significant NFL differences were found in PPCS participants compared with healthy individuals (p = 0.22). Intriguingly, a subset (9.3%) of PPCS participants initially exhibited abnormally high NFL levels (>9.7 pg/mL), which normalized upon follow-up (p = 0.032). Additionally, serum levels of the inflammatory markers, monocyte chemoattractant protein-1 (MCP-1/CCL2), and eotaxin-1/CCL11 were 25-40% lower than in healthy individuals (p ≤ 0.001). As hypothesized, PPCS participants exhibited a 22% reduction in the ratio of kynurenic acid to quinolinic acid (neuroprotective index) (p < 0.0001), indicating a shift towards the formation of neurotoxic metabolites.

CONCLUSION

NFL may serve as a biomarker to monitor recovery, and future studies should investigate the potential therapeutic benefits of modulating the kynurenine pathway to improve PPCS.

Psychometric evaluation and reference values for the German Postconcussion Symptom Inventory (PCSI-SR8) in children aged 8-12 years

Background

Post-concussion symptoms (PCS) are a common consequence of pediatric traumatic brain injury (pTBI). They include cognitive, emotional, and physical disturbances. To address the lack of age-adapted instruments assessing PCS after pTBI, this study examines the psychometric properties of the German 17-item post-TBI version of the Postconcussion Symptom Inventory (PCSI-SR8) in children aged 8-12 years. The study also aims to establish reference values based on data from a pediatric general population sample to better estimate the prevalence and clinical relevance of PCS after pTBI in clinical and research settings.

Methods

A total of 132 children aged 8-12 years from a post-acute TBI sample and 1,047 from a general population sample were included in the analyses. The questionnaire was translated from English into German and linguistically validated using forward and backward translation and cognitive debriefing to ensure comprehensibility of the developed version. Reliability and validity were examined; descriptive comparisons were made with the results of the English study. Measurement invariance (MI) analyses between TBI and general population samples were conducted prior to establishing reference values. Factors contributing to the total and scale scores of the PCSI-SR8 were identified using regression analyses. Reference values were calculated using percentiles.

Results

Most children (TBI: 83%; general population: 79%) rated at least one symptom as "a little" bothersome. The German PCSI-SR8 met the psychometric assumptions in both samples and was comparable to the English version. The four-factor structure comprising physical, emotional, cognitive, and fatigue symptoms could be replicated. The MI assumption was retained. Therefore, reference values could be provided to determine the symptom burden of patients in relation to a comparable general population. Clinical relevance of reported symptoms is indicated by a score of 8, which is one standard deviation above the mean of the general population sample.

Conclusion

The German version of the PCSI-SR8 is suitable for assessment of PCS after pTBI. The reference values allow for a more comprehensive evaluation of PCS following pTBI. Future research should focus on validation of the PCSI-SR8 in more acute phases of TBI, psychometric examination of the pre-post version, and child-proxy comparisons.

Factorial validity and comparability of the six translations of the Rivermead Post-Concussion Symptoms Questionnaire translations: results from the CENTER-TBI study

BACKGROUND

Comparison of patient-reported outcomes in multilingual studies requires evidence of the equivalence of translated versions of the questionnaires. The present study examines the factorial validity and comparability of six language versions of the Rivermead Post-Concussion Symptoms Questionnaire (RPQ) administered to individuals following traumatic brain injury (TBI) in the Collaborative European NeuroTrauma Effectiveness Research (CENTER-TBI) study.

METHODS

Six competing RPQ models were estimated using data from Dutch (n = 597), English (n = 223), Finnish (n = 213), Italian (n = 268), Norwegian (n = 263), and Spanish (n = 254) language samples recruited six months after injury. To determine whether the same latent construct was measured by the best-fitting model across languages and TBI severity groups (mild/moderate vs. severe), measurement invariance (MI) was tested using a confirmatory factor analysis framework.

RESULTS

The results did not indicate a violation of the MI assumption. The six RPQ translations were largely comparable across languages and were able to capture the same construct across TBI severity groups. The three-factor solution comprising emotional, cognitive, and somatic factors provided the best fit with the following indices for the total sample: χ2 (101) = 647.04, [Formula: see text]= 6.41, p < 0.001, CFI = 0.995, TLI = 0.994, RMSEA = 0.055, CI90%[0.051, 0.059], SRMR = 0.051.

CONCLUSION

The RPQ can be used in international research and clinical settings, allowing direct comparisons of scores across languages analyzed within the full spectrum of TBI severity. To strengthen the aggregated applicability across languages, further analyses of the utility of the response scale and comparisons between different translations of the RPQ at the item level are recommended.

Dizziness-Related Disability One Year after a Mild-to-Moderate TBI-A Follow-Up Study

Persisting dizziness and balance problems after mild-to-moderate traumatic brain injury (mmTBI) may result in considerable disability. The primary aim of this study was to explore the factors associated with dizziness-related disability one year post-injury. Data from 64 participants (mean age 39.4 [SD 13.0] years; 45 [70.3%] women) with mmTBI from a previous randomised controlled trial were analysed using simple and multiple regression analyses (Clinical Trials Registry #NCT01695577). The Dizziness Handicap Inventory one year (12.1, [SD1.6] months) post-injury was the dependent variable. Demographic and injury-related variables, clinical findings, and measures of post-injury symptoms and functioning (Rivermead Post-Concussion Symptoms Questionnaire, RPQ; Vertigo Symptom Scale-short form, VSS-SF; Hospital Anxiety and Depression Scale; Balance Error Scoring System; and High-Level Mobility Assessment Tool, HiMAT) at baseline (3.5 [SD 2.1] months post-injury) were the independent variables. Dizziness-related disability at one year was associated with pre-injury comorbidity, neck pain, higher RPQ, higher VSS-SF, and lower HiMAT scores (adjusted R2 = 0.370, F = 6.52 p < 0.001). In conclusion, the factors associated with dizziness-related disability one year post-injury, such as pre-injury comorbidity, neck pain, increased post-concussion symptom burden, increased dizziness symptom severity, and reduced balance and mobility, should be addressed early in the rehabilitation process to reduce patient burden.

The importance of screening for functional neurological disorders in patients with persistent post-concussion symptoms

BACKGROUND

Functional neurological disorder (FND) may commonly co-occur with persistent symptoms following a psychological trauma or physical injury such as concussion.

OBJECTIVE

To explore the occurrence of FND in a population with persistent post-concussion symptoms (PPCS) and the associations between FND and depression as well as anxiety in participants with PPCS.

METHODS

Sixty-three individuals with PPCS presenting to a specialized brain injury clinic completed the following questionnaires: screening for somatoform disorder conversion disorder subscale (SOM-CD), Rivermead post-concussion symptom questionnaire (RPQ), patient health questionnaire-9 (PHQ-9), and generalized anxiety disorder questionnaire- 7 (GAD-7). Both multiple linear regression and logistic regression were conducted to evaluate the relationship between questionnaires and adjust for covariates.

RESULTS

We found that total RPQ score (βˆ= 0.27; 95% CI = [0.16, 0.38]), GAD-7 score (βˆ= 0.71; 95% CI = [0.50, 0.92]) and PHQ-9 score (βˆ= 0.54; 95% CI = [0.32, 0.76]) were positively associated with SOM-CD score individually, after consideration of other covariates. Participants meeting the criteria for severe FND symptoms were 4.87 times more likely to have high PPCS symptom burden (95% CI = [1.57, 22.84]), 8.95 times more likely to have severe anxiety (95% CI = [3.31, 35.03]) and 4.11 times more likely to have severe depression symptom burden (95% CI = [1.77, 11.53]).

CONCLUSION

The findings of this study indicate an association between FND and post-concussion symptoms as well as an association between FND and symptoms of depression and anxiety in patients with PPCS. Patients with PPCS should be screened for FND to provide a more targeted treatment approach that includes somatic-focused interventions.