Abstract
Nearly one-third of individuals who sustain a mild traumatic brain injury (mTBI) experience persistent symptoms 3 months or longer, which can significantly impact their quality of life (QoL). These symptoms often span physical, cognitive, emotional, and sleep-related domains. To examine the relationship between symptom severity, QoL, and time since injury in individuals with persistent symptoms after mTBI, individuals with mTBI were recruited through a neurology clinic, with matched controls enrolled from the community. Participants completed the World Health Organization QoL-Short version (WHOQOL-BREF), assessing physical, psychological, social, and environmental QoL, the Post Concussion Symptom Scale (PCSS), measuring cognitive, physical, affective, and sleep symptoms, and time since injury. The Mann-Whitney U tests were used to compare outcomes between groups, and Spearman’s rank correlation was used to examine relationships between time since injury, PCSS, and QoL domains. Eighteen individuals with mTBI and 21 controls (mean age 55.28 ± 10.54 years) completed the study. The mTBI participants had higher symptom severity across all PCSS domains (p < 0.001) and lower QoL in all domains (p < 0.001). Environmental QoL was moderately correlated with all symptom domains, and physical QoL with physical and sleep symptoms (p < 0.05). Time since injury was not associated with symptom severity or QoL (p > 0.05). Persistent symptoms following mTBI are associated with lower QoL in middle-aged and older adults. Time since injury was not related to symptom severity or QoL. A multidimensional approach that addresses persistent symptoms, psychosocial factors, and environmental factors may improve functional recovery and QoL after injury.
Keywords
Introduction
Traumatic brain injury (TBI) is a leading cause of disability worldwide, affecting an estimated 64–74 million people annually, with 75–90% classified as mild traumatic brain injury (mTBI). 1 While most individuals recover within 3 months, around 15% continue to suffer from persistent symptoms several months after the initial injury.1–3 There are several factors associated with recovery, such as age and baseline function prior to the injury, with older adults having worse outcomes following mTBI.4,5
Individuals with persistent symptoms after mTBI experience symptoms ranging from headaches and dizziness to cognitive problems and mood changes. 6 These lingering symptoms have been shown to interfere with everyday activities in both young adults, making it difficult to socialize or complete cognitively demanding tasks,7,8 and older adults, making return to work difficult. 9 Likewise, persistent symptoms are associated with slower walking and turning speed in the younger population, 10 while a further decrease in gait speed has been observed in older adults during cognitively demanding walking tasks compared to healthy controls. 11 Lifestyle changes observed in people with persistent symptoms include change in driving habits, such as driving shorter distances and avoiding night driving, 12 as well as an inability to participate in leisure activities that they were able to prior to the injury. 13 These lifestyle changes may contribute to increased sedentary behaviors and poorer quality of life (QoL). 14
QoL is defined as a person’s overall well-being, encompassing physical, emotional, and social functioning, and represents the individual’s perception of their current state in relation to their goals and expectations. 15 Individuals with higher symptom burden after mTBI report decline in physical health, emotional well-being, and social engagement months after the initial injury, particularly among younger adults engaged in high levels of daily activities, a pattern that extends to older adults who remain active. 16 Even those individuals who report minimal symptoms early on, may develop new symptoms later or experience an increase in existing symptoms that interfere with daily life, 17 leading to reduced community participation, lower life satisfaction, and feelings of isolation. 18 While there is a relationship established between persistent mTBI symptoms and lower QoL, 16 the link between symptom severity and the distinct domains of QoL is not clear.
The aim of this study was to examine the relationship between symptom severity, QoL, and time since injury in middle-aged and older adults with persistent symptoms following an mTBI. We examined each domain of symptom severity (cognitive, physical, affective, and sleep) and the relationship with QoL domains (physical, psychological, social, and environmental). Our hypotheses were that (1) greater symptom severity as measured by the Post Concussion Symptom Scale (PCSS) would be associated with lower self-reported QoL measured by the WHOQOL-BREF, and (2) longer time since injury would be associated with decreased symptom severity and improved QoL.
Methods
This was a cross-sectional, comparative study conducted at the University of Kansas Medical Center in accordance with the Institutional Review Board requirements (STUDY00143522).
Participants
Participants with a diagnosis of mTBI were recruited through the neurology clinic and outpatient clinics at the Kansas University Health system through a neurologist (M.R.). Participants were included if they (1) were between 40 and 75 years of age; (2) had a diagnosis of mTBI coded by ICD-10 (S06.0X0A-S06.0X9S) criteria, which included a history of TBI and the presence of 3 or more of the following 8 symptoms: (1) headache, (2) dizziness, (3) fatigue, (4) irritability, (5) insomnia, (6) concentration or (7) memory difficulty, and (8) intolerance of stress, emotion, or alcohol; (3) had continued symptoms since the initial injury, picked up by the PCSS; (4) were between 6 weeks and 2 years since their injury. The age group that was included was an a priori decision to focus on middle-aged and older adults. Likewise, the time since injury (greater than 6 weeks) was determined a priori because of our interest in examining people with persistent symptoms.
Participants with mTBI were excluded if they had (1) a diagnosed neurological problem such as stroke, Multiple Sclerosis, Parkinson’s disease; (2) history of a visual or vestibular disorder prior to the mTBI; (3) had a history of cancer and received chemotherapy; or (4) if they were involved in litigation due to injury due to the added stress associated with litigation.
Healthy controls were recruited through word-of-mouth within and outside of the campus community if they did not have a prior history of diagnosed head injury and following the exclusion criteria as the mTBI group.
Study methods
After completing informed consent, demographic information, including age, sex, history of comorbidities, pain location and severity on a scale from 0 to 10, and time since injury, was gathered. Data presented here are part of a larger study.
Participants completed the WHOQOL-BREF, a subjective 26-item assessment tool that evaluates physical health (7 items), psychological (6 items), social relationships (3 items), and environmental domains (8 items). 15 Scores were transformed from raw data into a 0–100 scale, with higher scores representing better QoL. The WHOQOL-BREF has been validated in the TBI population across the spectrum of injury;17,19–23 however, few published articles focus exclusively on mTBI using the WHOQOL-BREF. Most research applies it to mixed-severity TBI cohorts from mild to severe.
Participants completed the PCSS, a 22-item subjective measure of symptoms rated on a Likert scale from 0 (“none”) to 6 (“severe”). The PCSS assesses four domains: cognitive, physical, affective, and sleep. Scores are summed to calculate a total PCSS score, with higher scores representing either a greater severity of symptoms or an increased number of symptoms.24,25
Statistical analyses
Baseline characteristics and demographics were summarized as mean and standard deviation for continuous, normally distributed variables (age) and median and quartiles (PCSS and WHOQOL-BREF) for those that were not normally distributed. Differences between the mTBI and control groups on the PCSS total score and individual domains, and WHOQOL-BREF domain scores were examined using the Mann-Whitney U tests. Spearman’s rank correlation analyses were used to examine the relationships between PCSS domain scores (cognitive, physical, affective, and sleep), WHOQOL-BREF domain scores (physical, psychological, social, and environmental), time since injury, and age in the mTBI group only. Multiple testing adjustments were carried out using Benjamini-Hochberg’s method. Correlations were interpreted as weak (0.10–0.39), moderate (0.40–0.69), strong (0.70–0.89), and very strong (>0.90). 26 The threshold for significance was set at p < 0.05. Data were analyzed using IBM SPSS Statistics (version 29.0.0.0).
Results
Demographics and group comparisons
Eighteen individuals in the mTBI group and 21 control subjects completed the study. Three out of 21 (14%) controls reported pain, which was primarily musculoskeletal (hip and neck) with an average pain rating of 4/10; however, 14 out of the 18 [77%] of participants with mTBI reported pain, with all 14 of those reporting either headaches (average 7.86/10) or cervical neck pain (average 4.89/10). Demographic characteristics, PCSS total scores and each domain score, and WHOQOL domain scores are shown in Table 1. As expected, PCSS scores were significantly higher in the mTBI group compared to the control group (p < 0.001). The WHOQOL-BREF domains (physical, psychological, social, and environmental) were significantly lower in the mTBI compared to the control group in all domains (p < 0.001).
Participant Demographics
*Indicates significant differences.
mTBI, mild traumatic brain injury.
Overall and domain-specific QoL responses
In response to the independent questions on the WHOQOL-BREF: (1) rate your overall QoL where (4 = “good,” 5 = “very good”), 100% of the controls selected either 4 or 5, compared to 50% in the mTBI group; (2) how satisfied are you with your health (4 = “satisfied,” 5 = “very satisfied”), 85% of the controls selected 4 or 5, while 22% in the mTBI group reported being satisfied, and only 1 person (5%) was very satisfied.
Average responses for each item within the WHOQOL-BREF separated into the four domains are presented in Figure 1.
WHOQOL-BREF questions 3–26 by domain, comparing controls and individuals with mild traumatic brain injury (mTBI). Controls are represented by triangles, and the mTBI group by circles. Each shape represents the group mean, with lines indicating the standard deviation. All questions demonstrated statistically significant differences between groups (p < 0.05).
Relationship Between Post-Concussion Symptoms and QOL
Physical health QoL showed moderately strong negative correlations with both physical (rho = −0.680; p = 0.02) and sleep (rho = −0.606; p = 0.03) symptom domains and no relationship with cognitive or affective symptom domains. Psychological QoL was moderately and negatively correlated with the affective symptom domain (rho = −0.560; p = 0.04), but no relationship was found with cognitive, physical, or sleep domains (p > 0.05). Environmental QoL showed moderate negative correlations with cognitive (rho = −0.545; p = 0.04), physical (rho = −0.621, p = 0.03), affective (rho = −0.656, p = 0.02), and sleep (rho = −0.550, p = 0.04) symptom domains. Social QoL showed no relationship with any of the symptom domains. Time since injury was not related to any QoL or symptom domain (p < 0.05). Age showed a moderate positive correlation with psychological QoL (rho = 0.48, p = 0.04) but none of the remaining domains (p > 0.05).
Discussion
The primary aim of this study was to determine how persistent symptoms following mTBI affect QoL in middle-aged and older adults and whether time since injury influences QoL or symptom severity. Our findings demonstrate that participants with mTBI report significantly lower QoL across all domains compared to healthy controls and that symptom burden, particularly physical, affective, cognitive, and sleep symptoms, is closely associated with reduced QoL. Importantly, time since injury was not related to symptom severity or QoL. These findings indicate that mTBI is not a transient or benign injury for some individuals, and recovery does not occur passively over time.
The strong association between symptom burden and QoL aligns with previous research indicating that persistent symptoms after mTBI negatively impact physical, psychological, and social functioning.16,27,28 Our domain-specific correlations provide additional nuance to the existing literature, showing that physical QoL was most strongly related to physical and sleep symptoms, while environmental QoL correlated with all symptom domains. These findings suggest that specific symptom profiles may differently impact distinct domains of QoL. They also underscore the multidimensional nature of recovery and suggest that interventions should be multifaceted to influence long-term outcomes.23,29
Individuals with mTBI in this study reported dissatisfaction with their health. These results are consistent with current evidence that individuals with mTBI have worse QoL than orthopedic trauma controls and similar QoL to those with moderate or severe TBI.16,27,28 Similarly, satisfaction with health was lower in the mTBI group, with only a small number reporting satisfaction. Although we did not explore the reasons behind dissatisfaction with health status, our findings suggest that persistent symptoms may influence an individual’s broader perception of well-being.
Interestingly, social QoL did not correlate with symptom severity, although mTBI participants reported less satisfaction with personal relationships and less support from friends compared to controls. Lack of support and understanding from family and friends has been described as the most significant difficulty faced by older adults following mTBI, as many post-injury symptoms are not outwardly visible.18,30 Satisfaction with sex life was also lower among participants with mTBI, though research specifically addressing sexual well-being after mild TBI remains sparse. Factors such as acceptance of the situation, optimism, and a strong support network have been identified as protective factors, potentially buffering the negative effects of ongoing symptoms and improving well-being. 30 In our sample, psychological QoL increased with age, with the older adults reporting high satisfaction and enjoyment with life, and minimal report of negative feelings.
Pain, particularly headaches and neck pain, was highly prevalent among participants and likely contributed to lower physical QoL. Prior studies have linked chronic post-traumatic headaches to disability and lower QoL.29,31,32 Pain interfered with daily activities in 95% of the mTBI participants compared to 61% of controls. Similarly, sleep disturbances, which were common in our sample, have been associated with fatigue, cognitive slowing, and poorer functional outcomes.1,27 These findings highlight the need for targeted management of pain and sleep symptoms as part of comprehensive rehabilitation.
A high proportion of participants reported the need for continued medical attention, a finding that has not been well documented in middle-aged and older adults but has been well described in the military population following mTBI.33,34 This reliance on medical care for persistent symptoms further indicate a lower level of functioning. Dissatisfaction with the ability to perform daily activities and reduced work capacity seen in mTBI participants aligns with previous research that describes functional and vocational impairments following mTBI.35,36
Lower environmental QoL scores in our study, reflecting dissatisfaction with safety, living conditions, transportation, and access to daily information, are novel and underexplored in the literature. Our findings of reduced opportunities for leisure activities alongside previously studied factors such as housing instability and limited financial resources post-mTBI have been linked to poorer recovery outcomes.27,28,35 Satisfaction with transportation was lower among individuals with mTBI, which may reflect post-injury limitations in driving and/or difficulty navigating public transportation. Cognitive impairments, lower satisfaction with life, anxiety, and depression were frequently reported by the mTBI group. These findings are aligned with findings from the TRACK-TBI study showing that affective symptoms are strong predictors of QoL.9,35,37,38
Contrary to our hypothesis, time since injury was not associated with symptom severity or QoL. This finding supports prior longitudinal studies showing that symptoms fluctuate, or new symptoms may develop with time.20,27,28 Recovery may be influenced by psychosocial, environmental, and symptom burdens rather than duration alone, and proactive identification and intervention are necessary to improve long-term outcomes.
This study’s limitations include its cross-sectional design, which limits the ability to draw causal inferences from the observed relationships. Participants with mTBI were recruited from the neurology outpatient clinics; therefore, they represent a sample of people who are symptomatic and actively seeking treatment. Self-reported data introduces the potential for recall bias and subjective interpretation. The modest sample size may reduce the statistical power to detect subtle associations. Socioeconomic status, psychiatric history, education, and access to care were not assessed and may have influenced QoL outcomes. Despite these limitations, the use of validated tools and the focus on middle-aged and older adults strengthen the relevance of our findings.
Conclusion
Our study findings suggest that many factors influence QoL after mTBI when symptoms persist. These factors include symptom severity, psychological support, environmental factors, sleep problems, and pain. Therefore, clinicians should adopt a multidimensional approach to screen for pain, sleep disturbances, symptom severity, as well as consider psychosocial and environmental support, to enhance QoL and functional recovery.
Transparency, Rigor, and Reproducibility
The dataset used for this study is a subset of a larger study. The primary goal of the larger study was to compare the cognitive workload during a visual scanning task and during ambulation between people with persistent symptoms after mTBI and controls. This was a cross-sectional study, without randomization or blinding. The sample size was calculated based on pupillometry data and a sample size of 25 subjects in each group was planned. The data presented in this article includes all subjects who completed the WHOQOL-BREF questionnaire. The study statistician has reviewed the statistical analysis, normality has been verified using scatter plots, and correction for multiple comparisons have been made using the Benjamini Hochberg method. Data from this study will be made available upon request.
Authors’ Contributions
L.J.D. was responsible for the conceptualization, formal analysis, funding acquisition, investigation, methodology, project administration, advising on the original draft and critical review of the article. P.H. was responsible for the formal analysis, writing of the original draft, and editing of the final article. P.C. was responsible for the conceptualization, formal analysis, methodology, review and editing of the final article. M.R. was responsible for the conceptualization, methodology, review and editing of the final article. H.D. was responsible for the conceptualization, formal analysis, methodology, review and editing of the final article.
Footnotes
Author Disclosure Statement
No competing financial interests exist.
Funding Information
This study was funded by a grant from the Department of Physical therapy, Rehabilitation Science, and Athletic Training at the University of Kansas Medical Center. Redcap at KUMC is supported by a CTSA grant (CTSA Award # UL1TR002366).