Exploring the Association between Personality Traits, Symptom Burden, and Return to Work after Mild-to-Moderate Traumatic Brain Injury.

Approximately 30% of individuals with mild traumatic brain injury (mTBI) experience persistent post-concussion symptoms (PPCS). Personality factors have been linked to PPCS, yet, the association between personality traits and outcomes after mTBI is poorly understood. The aim of this study was to evaluate the association between personality traits, PPCS, and return to work (RTW) in patients with mild-to-moderate traumatic brain injury (TBI). Data from eighty-seven participants with mild-to-moderate TBI were analyzed. Sociodemographic, injury, and work characteristics and depressive symptoms were recorded 2-3 months post-injury. Personality traits were measured using the NEO Five-Factor Inventory-3. PPCS and RTW were assessed 15 months post-injury. Multiple linear regression models were performed. The factors associated with more severe PPCS were female sex, higher levels of neuroticism, openness to experience and conscientiousness, extra-cranial injuries, and depressive symptoms. The factors associated with lower RTW were female sex, higher levels of neuroticism, and conscientiousness. However, after controlling for PPCS, personality traits were no longer significantly associated with RTW. In conclusion, specific personality traits were associated with more severe PPCS and may be indirectly associated with RTW via PPCS. Hence, personality traits may be important to assess to identify patients at risk of less favorable outcomes after mild-to-moderate TBI.

Stability and Change in Biopsychosocial Factors Associated With Fatigue 6 and 12 Months After Traumatic Brain Injury: An Exploratory Multilevel Study.

OBJECTIVE: To explore factors associated with stability and change in fatigue from 6 to 12 months following traumatic brain injury (TBI). SETTING: Combined in- and outpatient acute care and postacute rehabilitation settings. PARTICIPANTS: A total of 103 patients with confirmed intracranial injury were assessed 6 and/or 12 months following TBI. DESIGN: A prospective observational study with repeated measures at 2 time points, analyzed with a hybrid mixed-effects model. MAIN MEASURES: Primary outcomes were the fatigue factor derived from items from several fatigue patient-reported outcome measures (PROMs; Fatigue Severity Scale, Chalder Fatigue Scale, Giessen Subjective Complaints List-fatigue subscale, and Rivermead Post-Concussion Symptoms Questionnaire-fatigue item) Secondary outcomes were PROMs relating to pain, somatic and psychological distress, insomnia, sleepiness, personality traits, optimism, resilience, behavioral activation and inhibition, and loneliness, as well as neuropsychological measures. Demographic variables and injury severity characteristics were included as covariates. RESULTS: In multilevel regression, female sex, years of education, and 3 factors related to injury severity, somatic vulnerability, and psychosocial robustness were all significantly associated with variation in fatigue between subjects, and explained 61% of the variance in fatigue that was due to stable between-subject differences. Fatigue levels declined significantly over time. Changes in pain severity, somatic symptom burden, psychological distress, and behavioral inhibition were positively associated with changes in fatigue, explaining 22% of the variance in fatigue within subjects. CONCLUSIONS: The study demonstrated that several previously implicated factors show robust effects in distinguishing individuals with TBI on levels of fatigue, but only a few show additional within-subject associations across time. Pain severity, somatic symptom burden, psychological distress, and behavioral inhibition correlated with fatigue across time, implicating these factors as crucial targets for rehabilitation of patients with TBI who suffer from persistent fatigue.

Impact of Somatic Vulnerability, Psychosocial Robustness and Injury-Related Factors on Fatigue following Traumatic Brain Injury-A Cross-Sectional Study.

Fatigue is a common symptom after traumatic brain injuries (TBI) and a crucial target of rehabilitation. The subjective and multifactorial nature of fatigue necessitates a biopsychosocial approach in understanding the mechanisms involved in its development. The aim of this study is to provide a comprehensive exploration of factors relevant to identification and rehabilitation of fatigue following TBI. Ninety-six patients with TBI and confirmed intracranial injuries were assessed on average 200 days post-injury with regard to injury-related factors, several patient-reported outcome measures (PROMS) of fatigue, neuropsychological measures, and PROMS of implicated biopsychosocial mechanisms. Factor analytic approaches yielded three underlying factors, termed Psychosocial Robustness, Somatic Vulnerability and Injury Severity. All three dimensions were significantly associated with fatigue in multiple regression analyses and explained 44.2% of variance in fatigue. Post hoc analyses examined univariate contributions of the associations between the factors and fatigue to illuminate the relative contributions of each biopsychosocial variable. Implications for clinical practice and future research are discussed.

The role of pain and psychological distress in fatigue: a co-twin and within-person analysis of confounding and causal relations.

OBJECTIVE: Fatigue is a common symptom in somatic and mental illness. Musculoskeletal pain and psychological distress have in turn frequently been shown to be associated with fatigue across clinical conditions and in the general population. The study aims to disentangle direct effects from those due to mere confounding from shared etiologies. DESIGN: The study used genetically informative longitudinal twin data, through a co-twin control design with an additional within-person dimension. METHODS: Data on fatigue, pain and distress from 2196 mono - and dizygotic twins from the Norwegian Twin Registry examined at two time points five years apart was analyzed using multilevel generalized linear regression modeling. Fatigue was regressed on pain and distress, with further controls added for confounding from genetic and stable non-shared environmental sources. RESULTS: Pain and distress had a significant impact on fatigue at genetic, stable non-shared environmental and time-varying levels, even when controlling for somatic comorbidity. CONCLUSION: The findings indicate that a significant proportion of the association between fatigue, pain and distress is due to genetic and environmental confounding. Pain and distress exert significant, albeit smaller effects on fatigue even when controlling for genetic and stable environmental contributions, indicating direct effects. Potential etiological pathways and underlying mechanisms are discussed.

Frequency of fatigue and its changes in the first 6 months after traumatic brain injury: results from the CENTER-TBI study.

BACKGROUND: Fatigue is one of the most commonly reported subjective symptoms following traumatic brain injury (TBI). The aims were to assess frequency of fatigue over the first 6 months after TBI, and examine whether fatigue changes could be predicted by demographic characteristics, injury severity and comorbidities. METHODS: Patients with acute TBI admitted to 65 trauma centers were enrolled in the study Collaborative European NeuroTrauma Effectiveness Research in TBI (CENTER-TBI). Subjective fatigue was measured by single item on the Rivermead Post-Concussion Symptoms Questionnaire (RPQ), administered at baseline, three and 6 months postinjury. Patients were categorized by clinical care pathway: admitted to an emergency room (ER), a ward (ADM) or an intensive care unit (ICU). Injury severity, preinjury somatic- and psychiatric conditions, depressive and sleep problems were registered at baseline. For prediction of fatigue changes, descriptive statistics and mixed effect logistic regression analysis are reported. RESULTS: Fatigue was experienced by 47% of patients at baseline, 48% at 3 months and 46% at 6 months. Patients admitted to ICU had a higher probability of experiencing fatigue than those in ER and ADM strata. Females and individuals with lower age, higher education, more severe intracranial injury, preinjury somatic and psychiatric conditions, sleep disturbance and feeling depressed postinjury had a higher probability of fatigue. CONCLUSION: A high and stable frequency of fatigue was found during the first 6 months after TBI. Specific socio-demographic factors, comorbidities and injury severity characteristics were predictors of fatigue in this study.