Patient Attribution of Posttraumatic Symptoms to Brain Injury Versus PTSD in Military-Related Mild TBI
Publication: The Journal of Neuropsychiatry and Clinical Neurosciences
Abstract
Objective:
Persistent cognitive, somatic, and neuropsychiatric symptoms following mild traumatic brain injury (TBI) are influenced by posttraumatic stress disorder (PTSD), particularly in military patients. The authors evaluated the degree to which military service members with a history of mild TBI attributed posttraumatic symptoms to TBI versus PTSD.
Methods:
Service members (N=372) with mild TBI were surveyed about the severity of posttraumatic symptoms across four symptom clusters (cognitive, affective, somatosensory, and vestibular) with the Neurobehavioral Symptom Inventory (NSI). Participants rated the degree to which they believed TBI, PTSD, or other conditions contributed to their symptoms. Differences in cognitive, affective, somatosensory, and vestibular symptom severity were evaluated across participants with TBI, PTSD, or combined TBI-PTSD attribution. Logistic regression was used to evaluate the association between symptom profiles and attribution.
Results:
Participants attributed symptoms mostly to TBI, followed by insufficient sleep, PTSD, chronic pain, depression, and deployment-readjustment stress. PTSD and combined TBI-PTSD attribution were associated with higher total NSI scores (39.5 and 51.6, respectively), compared with TBI attribution only (31.4) (F=29.08, df=3, 358, p<0.01), as well as higher scores in every symptom category. More severe affective symptoms were associated with decreased odds of TBI attribution (odds ratio=0.90, 95% CI=0.83–0.97) and increased odds of PTSD attribution (odds ratio=1.14, 95% CI=1.03–1.26). A PTSD diagnosis was highly associated with PTSD attribution (odds ratio=2.44, 95% CI=1.07–5.58).
Conclusions:
The nature and severity of posttraumatic symptoms appear to play a role in patient beliefs about the causes of symptoms, whether from TBI or PTSD.
Traumatic brain injuries (TBIs) and their potential for long-term sequelae have garnered significant public attention in the past decade, particularly within active duty military and veteran populations (1–3). Data published by the Defense and Veterans Brain Injury Center (DVBIC) estimate that at least 379,519 service members sustained a TBI between 2000 and 2018, of which more than 80% were classified as mild (4). Patients with TBI, including mild TBI, often experience persistent somatic, cognitive, and neuropsychiatric symptoms, including headaches, dizziness, cognitive impairment, sensory deficits, anxiety, irritability, and depression (5–11). Although estimates of symptom prevalence differ, one study found that at least 53% of patients with TBI reported three or more symptoms 1 year after injury (9).
However, the concept of postconcussion syndrome (PCS), as these persistent symptoms are termed, remains controversial because of the subjective nature of diagnosis and the potential for misdiagnosis (12). PCS lacks specificity and overlaps heavily with various psychiatric disorders (13–15). In many cases, PCS is clinically indistinguishable from conditions such as posttraumatic stress disorder (PTSD) and major depressive disorder. This is especially true in military patients, given the high coprevalence of TBI, PTSD, and depression in this population (3, 14, 16). Indeed, research has demonstrated that the presence of PTSD in combat veterans is much more predictive of the presence and severity of PCS than the actual brain injury itself (14–20). The controversial nature of PCS as a diagnosis has led researchers to advocate for the more inclusive term of “posttraumatic symptoms” to describe all persistent symptoms after a TBI, accounting for the multiple contributing neurologic and psychiatric etiologies (21). This is important, given that inadequate treatment of PTSD and major depressive disorder appears to worsen outcomes for TBI (22). Conversely, the presence of TBI appears to complicate treatment of PTSD and major depressive disorder (23).
Other important factors contributing to the persistence of posttraumatic symptoms after a TBI are the attributions of symptoms and expectations about recovery (24–26). Multiple studies have suggested that patients misattribute many incidental or unrelated symptoms to their TBI, resulting in overall higher burden of symptoms (24, 25). Such patients may be less likely to address underlying mental health needs and thus less likely to recover. However, a recent study by Hardy et al. (27), which examined military service members with mild TBI, found that many of these patients appeared to recognize the contribution of mental health conditions, such as PTSD and depression, to their posttraumatic symptoms. To our knowledge, no other prior research has specifically examined patient attribution of posttraumatic symptoms to conditions other than TBI, such as PTSD or depression, and how patient attribution may be associated with the severity of symptom reporting.
The purpose of this study was to further explore the degree to which patients with a history of TBI attribute posttraumatic symptoms to their TBI versus PTSD or to other etiologies. We also examined how this attribution is associated with the severity of symptoms reported across various symptom domains (cognitive, affective, somatosensory, and vestibular). We examined the factors associated with the differences in attribution of symptoms to either TBI, PTSD, or both. We hypothesized that patients who attribute their symptoms to TBI have a different symptom profile from those who attribute their symptoms to PTSD. The findings of this research will assist in understanding the complex experiences of those with posttraumatic symptoms and help guide care for such patients.
Methods
Participants
This retrospective study analyzed data collected between July 2014 and June 2017 by the DVBIC site at Brooke Army Medical Center. The study included active duty service members stationed in the area who screened positive for a history of TBI. DVBIC recruited participants from primary and specialty care clinics as well as health screening fairs. A DVBIC research assistant confirmed the TBI diagnosis by using chart review and patient interview. TBIs were further classified as mild, moderate, or severe according to Department of Defense criteria—based on the estimated duration of loss or alteration of consciousness and abnormalities on neuroimaging (2). The vast majority of the TBIs were mild, which is defined as a loss of consciousness for less than 30 minutes, alteration of consciousness or posttraumatic amnesia for less than 24 hours, and a lack of structural abnormalities on brain imaging. Because of the small number of moderate or severe TBIs in the sample and the significant clinical heterogeneity that exists across TBI severity, we limited this study to participants with mild TBIs. The 59th Medical Wing Institutional Review Board provided approval prior to study initiation.
Measures
We collected basic demographic and military-specific data for study participants, including age, gender, race/ethnicity, education, branch of service, and military rank. Details collected about the index TBI included length of time since injury, whether the injury occurred during combat, and whether the participant was awaiting a medical discharge from the military. Medical discharge was of particular interest, given that service members who are eligible for disability based on certain injuries or diagnoses (e.g., TBI) may report or attribute their symptoms differently, compared with those who are not undergoing medical discharge from the military. Finally, we assessed the presence of PTSD (ICD-10-CM code F43.1) or major depressive disorder (ICD-10-CM codes F32* and F33*) on the basis of reviews of the service members’ medical records.
We used the Neurobehavioral Symptom Inventory (NSI) to evaluate the severity of posttraumatic symptoms. The NSI is a 22-item patient questionnaire that records the severity of various somatic, sensory, vestibular, cognitive, and affective complaints commonly associated with mild TBI; it has been well validated in active duty and veteran populations (5, 28, 29). Given the inherent subjectivity of the NSI and the degree of overlap of TBI with other psychiatric and neurologic conditions, various studies have sought to derive factor structure models that provide greater specificity for TBI-related symptoms and discrimination among clinical subgroups (29, 30).The four-factor model utilized in this study has been shown to have the best overall model fit (29). The four factors include vestibular, cognitive, somatosensory, and affective symptom clusters. Vestibular symptoms include dizziness and balance-coordination problems; somatosensory symptoms include blurry vision, numbness-tingling, photo- or phonophobia, and dysgeusia; cognitive symptoms include forgetfulness, slowed processing, and difficulty making decisions; and affective symptoms include fatigue, insomnia, anxiety, depression, irritability, and poor frustration tolerance.
An additional brief survey, designed for this study, evaluated the degree to which study participants attributed posttraumatic symptoms to their TBI versus other clinical etiologies. The survey asked, “Considering your current symptoms, how much do you think that they are due to each of the following: TBI, pain, lack of sleep, PTSD, depression, deployment-related stress, or readjustment stress?” Responses followed a Likert scale: 0, not at all; 1, somewhat; 2, moderately; 3, very much; or 4, completely. Responses were not mutually exclusive; participants could attribute symptoms very much or completely in more than one category. To differentiate participants who attributed symptoms predominantly to TBI over PTSD, predominantly to PTSD over TBI, or both TBI and PTSD together, we developed new variables in the following manner: Those who scored TBI at least 2 points above PTSD on the Likert attribution scale were designated as TBI-predominant attribution. Those who scored PTSD at least 2 points above TBI were designated as PTSD-predominant attribution. Those who scored both TBI and PTSD as at least a 2 (moderately) were designated as combined TBI-PTSD attribution.
Statistical Analysis
We performed descriptive statistics for all demographic, military, and injury-related variables listed above. We calculated means and 95% confidence intervals (CIs) for each attribution category. We also calculated mean total NSI score, four subscale scores, and individual item scores for the TBI-predominant, PTSD-predominant, and combined TBI-PTSD attribution groups. We statistically compared means across groups with two-tailed analysis of variance. We used logistic regression analysis to determine the relative contribution of vestibular, somatic, cognitive, and affective symptoms to the likelihood that participants attributed symptoms to TBI, PTSD, or both. Attribution was selected as the outcome variable on the basis of the a priori assumption that the symptoms patients experience influence the attribution of those symptoms. The regressions were adjusted for age, gender, race, ethnicity, education, pending medical discharge, time since injury, the presence of a PTSD diagnosis, and whether the TBI was sustained during military combat—all factors that may theoretically affect both symptoms and attribution. Odds ratios, Z scores, p values, and 95% confidence intervals were reported for each variable in the regression.
Results
Population Characteristics
A total of 372 active duty service members were included in the study. Table 1 summarizes data on characteristics of the sample. The mean age was 36.3 years (SD=7.9), and the mean years of service was 14.4 (SD=7.1). The vast majority were male (86.8%), white (80.1%), and in the Army (91.4%). A significant proportion (78.2%) had education or vocational training beyond high school, and 19.9% were officers. The mean time elapsed since the index TBI was >4 years (55.5 months, SD=50.3. Forty-two percent of TBIs reportedly occurred during military combat. Twenty-five percent of participants were awaiting possible medical discharge from the military. Psychiatric comorbidity in this population was quite high, with 42.7% of service members currently diagnosed as having PTSD and 32.3% as having depression.
| Characteristic | N | % |
|---|---|---|
| Demographic | ||
| Age (years) (mean±SD) | 36.3 | 7.9 |
| Female | 49 | 13.2 |
| Race/ethnicity | ||
| Black | 73 | 19.6 |
| White | 298 | 80.1 |
| Hispanic or Latino (of any race) | 99 | 26.6 |
| Highest level of education | ||
| No high school diploma | 6 | 1.6 |
| High school diploma or GED | 71 | 19.1 |
| Technical school | 75 | 20.4 |
| Associate’s degree | 77 | 20.9 |
| Bachelor’s degree | 95 | 25.8 |
| Master’s degree | 33 | 9.0 |
| Doctoral degree | 11 | 3.0 |
| Military | ||
| Number of years in service (mean±SD) | 14.4 | 7.1 |
| Officer | 74 | 19.9 |
| Army (active duty, reserves, guard) | 340 | 91.4 |
| Navy (active duty, reserves) | 7 | 1.9 |
| Air Force (active duty) | 20 | 5.4 |
| Injury | ||
| Combat TBI | 154 | 41.5 |
| Months since injury (mean±SD) | 55.5 | 50.3 |
| Pending medical dischargea | 93 | 25.2 |
| Mental health conditionb | ||
| Preinjury posttraumatic stress disorder (PTSD) | 32 | 8.6 |
| Preinjury depression | 43 | 11.6 |
| Current PTSD | 159 | 42.7 |
| Current depression | 120 | 32.3 |
a
Discharge pertains to service members awaiting potential separation from the military for medical causes.
b
Data are based on diagnoses documented in medical records before or after injury.
Symptom Attribution
The mean level of symptom attribution to TBI and each of the other six categories is presented in Figure 1. On average, participants attributed their posttraumatic symptoms more strongly to TBI (mean=2.15, SD=1.16) than to any other category, with most attributing their symptoms at least moderately to TBI. Lack of sleep was the second highest category (mean=2.02, SD=1.37), followed by PTSD (mean=1.79, SD=1.51), pain (mean=1.79, SD=1.32), depression (mean=1.38, SD=1.41), readjustment stress (mean=1.35, SD=1.43), and deployment stress (mean=1.14, SD=1.15).
FIGURE 1. Attribution of posttraumatic symptoms among service members with a history of mild traumatic brain injury (TBI)a
a Participants rated how much they attributed their symptoms to each cause. Responses were not mutually exclusive. Points represent arithmetic means of the score for each variable, and error bars represent 95% confidence intervals. PTSD=posttraumatic stress disorder.
The mean scores for each of the individual symptom items in the NSI, as well as the total subscale score and overall total NSI score, are presented in Table 2. Fourteen of the 372 study participants are not included in this analysis due to missing data. NSI scores are stratified by how participants attributed their symptoms (TBI predominant, PTSD predominant, combined TBI-PTSD, or neither). Mean total NSI scores, symptom subscale scores, and each individual symptom score differed significantly across all attribution categories (all p values <0.01). Compared with TBI attribution, PTSD attribution was associated with higher mean symptom scores. Combined TBI-PTSD attribution was associated with the highest mean symptom scores across all categories.
| Neither (N=161) | TBI predominant (N=80) | PTSD predominant (N=40) | Combined TBI and PTSD (N=77) | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Scale or subscale | Mean | SD | Mean | SD | Mean | SD | Mean | SD | Fb | p |
| NSI total score | 30.5 | 18.0 | 31.4 | 17.7 | 39.5 | 17.0 | 51.6 | 15.2 | 29.08 | <0.01 |
| Vestibular subscale | 2.7 | 2.7 | 3.1 | 2.8 | 3.1 | 2.5 | 4.9 | 2.8 | 12.10 | <0.01 |
| Dizziness | 0.9 | 1.0 | 1. | 1.1 | 0.9 | 1.0 | 1.7 | 1.1 | 9.69 | <0.01 |
| Loss of balance | 0.8 | 1.0 | 1.0 | 1.1 | 1.0 | 1.0 | 1.7 | 1.2 | 10.76 | <0.01 |
| Poor coordination | 0.9 | 1.1 | 1.0 | 1.1 | 1.2 | 1.2 | 1.6 | 1.2 | 6.01 | <0.01 |
| Somatosensory subscale | 7.8 | 5.7 | 8.8 | 5.5 | 10.0 | 5.3 | 14.1 | 5.3 | 23.67 | <0.01 |
| Headaches | 2.0 | 1.5 | 2.4 | 1.2 | 2.4 | 1.3 | 2.9 | 1.2 | 8.61 | <0.01 |
| Nausea | 0.5 | 0.9 | 0.8 | 1.1 | 0.8 | 1.0 | 1.0 | 1.0 | 5.10 | <0.01 |
| Impaired vision | 0.9 | 1.1 | 0.8 | 1.1 | 1.2 | 1.2 | 1.9 | 1.3 | 15.83 | <0.01 |
| Sensitivity to light | 1.2 | 1.3 | 1.5 | 1.4 | 1.4 | 1.5 | 2.3 | 1.4 | 11.61 | <0.01 |
| Sensitivity to noise | 1.4 | 1.2 | 1.5 | 1.3 | 1.9 | 1.3 | 2.5 | 1.3 | 16.05 | <0.01 |
| Numbness or tingling | 1.5 | 1.3 | 1.3 | 1.3 | 2 | 1.3 | 2.4 | 1.3 | 11.34 | <0.01 |
| Change in taste or smell | 0.4 | 0.9 | 0.5 | 0.9 | 0.3 | 0.7 | 1.1 | 1.4 | 10.36 | <0.01 |
| Cognitive subscale | 6.7 | 4.4 | 6.8 | 4.4 | 8.5 | 4.3 | 10.7 | 3.9 | 16.59 | <0.01 |
| Poor concentration or attention | 1.9 | 1.4 | 1.9 | 1.4 | 2.5 | 1.3 | 2.9 | 1.2 | 12.43 | <0.01 |
| Forgetfulness | 2.0 | 1.2 | 2.2 | 1.3 | 2.6 | 1.2 | 3.1 | 1.1 | 15.70 | <0.01 |
| Difficulty making decisions | 1.2 | 1.2 | 1.2 | 1.2 | 1.6 | 1.4 | 2.2 | 1.2 | 12.55 | <0.01 |
| Impaired organization or task completion | 1.6 | 1.3 | 1.6 | 1.3 | 1.9 | 1.4 | 2.5 | 1.2 | 8.82 | <0.01 |
| Affective subscale | 11.3 | 6.2 | 10.4 | 6.3 | 15.4 | 5.7 | 17.6 | 5.3 | 26.38 | <0.01 |
| Fatigue | 2.0 | 1.2 | 2.0 | 1.4 | 2.6 | 1.4 | 3.1 | 1.1 | 15.58 | <0.01 |
| Insomnia | 2.4 | 1.4 | 2.3 | 1.6 | 3.0 | 1.4 | 3.3 | 1.0 | 10.71 | <0.01 |
| Anxiety | 2.0 | 1.3 | 1.8 | 1.3 | 2.7 | 1.2 | 3.0 | 1.1 | 18.02 | <0.01 |
| Depressed mood | 1.3 | 1.3 | 1.0 | 1.3 | 2.0 | 1.4 | 2.4 | 1.4 | 20.11 | <0.01 |
| Irritability | 2.0 | 1.3 | 1.8 | 1.4 | 2.9 | 1.3 | 2.9 | 1.1 | 17.12 | <0.01 |
| Low frustration tolerance | 1.7 | 1.4 | 1.6 | 1.4 | 2.3 | 1.4 | 2.8 | 1.1 | 14.72 | <0.01 |
a
Participants were categorized according to whether they attributed symptoms predominantly to TBI over posttraumatic stress disorder (PTSD) (TBI predominant), to PTSD over TBI (PTSD predominant), to both TBI and PTSD together (combined), or to some other etiology (neither). Fourteen of the 372 participants were not analyzed due to missing data. NSI scores for each individual symptoms range from 0 to 4. Total possible NSI scores range from 0 to 88. Higher scores indicate greater severity of symptoms.
b
The df value for each test was 3, 358. All p values are statistically significant.
The results of the logistic regression analysis are summarized in Table 3. The results indicate that more severe affective symptoms were associated with decreased odds of TBI-predominant attribution (odds ratio=0.90, 95% CI=0.83–0.97) but increased odds of PTSD-predominant attribution (odds ratio=1.14, 95% CI=1.03–1.26) and combined attribution (odds ratio=1.09, 95% CI=1.00–1.18). In other words, for each additional point on the NSI affective subscale, the odds of attributing symptoms to TBI rather than PTSD dropped approximately 10%, whereas the odds of attributing symptoms to PTSD rather than TBI increased 14% and the odds of attributing symptoms to both TBI and PTSD increased 9%. Higher somatosensory symptoms were associated with increased odds of attributing to both TBI and PTSD (odds ratio=1.11, 95% CI=1.02–1.20). The odds ratios for cognitive and vestibular symptoms were not statistically significant. Among the other variables included in the model, a diagnosis of PTSD was associated with much lower odds of TBI-predominant attribution (odds ratio=0.20, 95% CI=0.09–0.43) and much higher odds of PTSD-predominant attribution (odds ratio=2.44, 95% CI=1.07–5.58). No other variables were statistically significant.
| TBI predominant | PTSD predominant | Combined TBI and PTSD | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Variable | Odds ratio | Z | p | 95% CI | Odds ratio | Z | p | 95% CI | Odds ratio | Z | p | 95% CI |
| Age (years) | 0.98 | –0.89 | 0.37 | 0.94, 1.02 | 1.01 | 0.21 | 0.84 | 0.95, 1.06 | 1.02 | 0.77 | 0.44 | 0.97, 1.06 |
| Female | 1.92 | 1.69 | 0.09 | 0.90, 4.09 | 1.07 | 0.13 | 0.90 | 0.37, 3.12 | 0.68 | –0.82 | 0.41 | 0.27, 1.71 |
| Black race | 1.19 | 0.46 | 0.65 | 0.56, 2.53 | 0.98 | –0.18 | 0.86 | 0.81, 1.19 | 0.98 | –0.41 | 0.68 | 0.89, 1.08 |
| Hispanic or Latino | 0.63 | –1.46 | 0.14 | 0.33, 1.17 | 1.36 | 0.73 | 0.47 | 0.60, 3.10 | 1.05 | 0.16 | 0.87 | 0.56, 2.00 |
| Education level | 1.14 | 1.17 | 0.24 | 0.91, 1.44 | 0.95 | –0.39 | 0.70 | 0.73, 1.24 | 0.95 | –0.51 | 0.61 | 0.77, 1.17 |
| Combat TBI | 0.87 | –0.44 | 0.66 | 0.46, 1.62 | 0.98 | –0.06 | 0.95 | 0.46, 2.07 | 1.66 | 1.53 | 0.13 | 0.87, 3.18 |
| Pending medical dischargeb | 0.64 | –1.10 | 0.27 | 0.29, 1.42 | 1.12 | 0.29 | 0.77 | 0.51, 2.46 | 0.91 | –0.28 | 0.78 | 0.48, 1.74 |
| Time since injury | 0.99 | –1.93 | 0.05 | 0.99, 1.00 | 1.01 | 1.53 | 0.13 | 1.00, 1.01 | 1.00 | –0.36 | 0.72 | 0.99, 1.01 |
| PTSD diagnosisc | 0.20 | –4.09 | <0.01 | 0.09, 0.43 | 2.44 | 2.11 | 0.04 | 1.07, 5.58 | 1.33 | 0.86 | 0.39 | 0.70, 2.53 |
| NSI subscale scored | ||||||||||||
| Vestibular | 1.02 | 0.25 | 0.80 | 0.88, 1.17 | 0.92 | –0.86 | 0.39 | 0.76, 1.11 | 1.00 | 0.04 | 0.97 | 0.87, 1.15 |
| Somatosensory | 1.04 | 0.94 | 0.35 | 0.96, 1.13 | 0.97 | –0.73 | 0.47 | 0.88, 1.06 | 1.11 | 2.51 | 0.01 | 1.02, 1.20 |
| Cognitive | 1.09 | 1.74 | 0.08 | 0.99, 1.21 | 0.91 | –1.38 | 0.17 | 0.80, 1.04 | 1.03 | 0.49 | 0.63 | 0.92, 1.14 |
| Affective | 0.90 | –2.71 | <0.01 | 0.83, 0.97 | 1.14 | 2.59 | 0.01 | 1.03, 1.26 | 1.09 | 1.93 | 0.05 | 1.00, 1.18 |
a
Participants attributed symptoms predominantly to TBI over PTSD (TBI predominant), predominantly to PTSD over TBI (PTSD predominant), or to both TBI and PTSD together (combined). Statistical significance between groups is indicated in bold.
b
Discharge pertains to service members awaiting potential separation from the military for medical causes.
c
Data indicate the presence or absence of current PTSD diagnosis on the basis of medical record review.
d
NSI=Neurobehavioral Symptom Inventory.
Discussion
This study demonstrated that service members with a history of mild TBI often attributed their persistent symptoms to conditions other than their brain injury. In addition, this finding suggests a clear association between the severity of posttraumatic symptoms across symptom categories and the degree to which patients attribute those symptoms to TBI versus PTSD.
After the analysis controlled for other contributing factors, service members who had been diagnosed as having PTSD were more likely to attribute posttraumatic symptoms to PTSD rather than to TBI. Those who reported more severe affective symptoms were less likely to attribute these symptoms to TBI alone and more likely to attribute them to PTSD.
Of interest, vestibular and somatosensory symptoms, which seem the most specific for TBI and least likely to overlap with PTSD, were not predictive of attribution to TBI over PTSD. Service members who reported higher somatosensory symptoms were more likely to attribute symptoms to both TBI and PTSD. In fact, a higher burden of symptoms across all categories was associated with a higher likelihood of attributing symptoms to both TBI and PTSD.
Another interesting finding is the fact that lack of sleep figured so prominently in patient attribution of posttraumatic symptoms. Both TBI and PTSD commonly lead to chronic insomnia and other sleep disorders. In addition, poor sleep can independently contribute to many of the vestibular, somatosensory, cognitive, and affective symptoms that are measured by the NSI (31, 32). Thus lack of sleep in this patient population potentially represents an underaddressed clinical need that warrants additional study and intervention.
Because this study was cross-sectional and observational, it was unable to prove a causal pathway across diagnoses, symptom severity, and symptom attribution. We designed the logistic regressions with attribution as the outcome, suggesting that symptoms predict attribution. However, it also conceivable that attribution predicts symptoms, as some studies have suggested (24, 25). In other words, patients may experience or report different symptoms based on their attributions of those symptoms to TBI or PTSD. This relationship between symptoms and attribution is likely bidirectional, as well as mediated by other factors not accounted for in this study, such as underlying patient beliefs, resilience, and distress tolerance.
This study supports existing literature demonstrating the strong overlap of symptoms between mild TBI and PTSD. The study is unique in that it focused specifically on patient attribution of symptoms. Patient beliefs and expectations about their health conditions play a vital role both in the type of health care patients seek out and in their recovery from those conditions, which may be particularly true in the case of co-occurring TBI and PTSD. Those who attribute symptoms only to their brain injury may be less likely to seek out mental health care to address these symptoms, whereas those who believe the symptoms are a result of PTSD may be more likely to engage in mental health care (33). Thus service members with PCS could be much better served by recognition and treatment of psychiatric comorbidities. More research is needed to determine whether attribution does, in fact, determine the types of health care services patients with TBI seek out and whether attribution also influences recovery.
This study had a few key limitations. First, it examined only military service members with mild TBI, many of whom were several months or years out from their injury. Thus the study may not be very representative of other TBI patient populations, such as concussed athletes or those with more severe TBIs. Second, the results are based largely on subjective, patient-reported data and must be interpreted as such. Results may vary across patients because of differences in individual interpretation of the questions and rating scales. The NSI is an inherently subjective method for measuring the severity of posttraumatic symptoms and has relatively poor specificity for TBI, causing some to argue for more objective methods of measurement (34). Nevertheless, the NSI was well suited for this study because it is focuses on patient-reported symptoms. Third, the data presented are cross-sectional rather than longitudinal, as discussed above. We were unable to track the evolution of symptoms or attribution of symptoms, which may have provided additional useful information. Further research can examine how attribution changes over time as certain symptoms persist or how attribution to TBI versus PTSD influences the type of health care resources sought and the timeline of recovery.
Conclusions
Persistent cognitive, somatic, and neuropsychiatric symptoms following a mild TBI are a complex phenomenon heavily influenced by psychiatric comorbidity and patient expectations. The degree to which patients believe their symptoms are a result of TBI versus PTSD was found to be associated not only with the severity of the symptoms but also with the type of symptoms reported. By better understanding patients’ experiences and beliefs regarding posttraumatic symptoms, we can provide more effective and compassionate care.
Footnote
The views, opinions, and findings contained in this article are those of the authors and should not be construed as an official position, policy, or decision of Brooke Army Medical Center, the U.S. Army Medical Department, the U.S. Army Office of the Surgeon General, the Department of the Army, the Department of the Air Force, the U.S. Department of Defense, or the U.S. government unless so designated by other official documentation.
References
1.
DePalma RG, Hoffman SW: Combat blast related traumatic brain injury (TBI): decade of recognition; promise of progress. Behav Brain Res 2018; 340:102–105
2.
VA/DoD Clinical Practice Guideline for the Management of Concussion–Mild Traumatic Brain Injury. Washington, DC, Department of Veterans Affairs and Department of Defense, 2016
3.
Carlson K, Kehle S, Meis L: The Assessment and Treatment of Individuals With History of Traumatic Brain Injury and Post-Traumatic Stress Disorder: A Systematic Review of the Evidence. VA Evidence Synthesis Program Reports. Washington, DC, Department of Veterans Affairs, 2009
4.
Worldwide TBI Numbers. Falls Church, Va, Military Health System, 2018. https://health.mil/Military-Health-Topics/Conditions-and-Treatments/Physical-Disability/Traumatic-Brain-Injury/Worldwide-TBI-numbers
5.
Cicerone KD: Persistent postconcussion syndrome: the structure of subjective complaints after mild traumatic brain injury. J Head Trauma Rehabil 1995; 10:1–17
6.
Meares S, Shores EA, Taylor AJ, et al: The prospective course of postconcussion syndrome: the role of mild traumatic brain injury. Neuropsychology 2011; 25:454–465
7.
Ouellet M-C, Beaulieu-Bonneau S, Sirois M-J, et al: Depression in the first year after traumatic brain injury. J Neurotrauma 2018; 35:1620–1629
8.
Fann JR, Hart T, Schomer KG: Treatment for depression after traumatic brain injury: a systematic review. J Neurotrauma 2009; 26:2383–2402
9.
Dikmen S, Machamer J, Fann JR, et al: Rates of symptom reporting following traumatic brain injury. J Int Neuropsychol Soc 2010; 16:401–411
10.
Schwab K, Terrio HP, Brenner LA, et al: Epidemiology and prognosis of mild traumatic brain injury in returning soldiers: a cohort study. Neurology 2017; 88:1571–1579
11.
Mittenberg W, Strauman S: Diagnosis of mild head injury and the postconcussion syndrome. J Head Trauma Rehabil 2000; 15:783–791
12.
Evans RW: Persistent post-traumatic headache, postconcussion syndrome, and whiplash injuries: the evidence for a non-traumatic basis with an historical review. Headache 2010; 50:716–724
13.
Hill JJ 3rd, Mobo BHP Jr, Cullen MR: Separating deployment-related traumatic brain injury and posttraumatic stress disorder in veterans: preliminary findings from the Veterans Affairs traumatic brain injury screening program. Am J Phys Med Rehabil 2009; 88:605–614
14.
Wilk JE, Herrell RK, Wynn GH, et al: Mild traumatic brain injury (concussion), posttraumatic stress disorder, and depression in US soldiers involved in combat deployments: association with postdeployment symptoms. Psychosom Med 2012; 74:249–257
15.
Seal KH, Bertenthal D, Samuelson K, et al: Association between mild traumatic brain injury and mental health problems and self-reported cognitive dysfunction in Iraq and Afghanistan Veterans. J Rehabil Res Dev 2016; 53:185–198
16.
Hoge CW, McGurk D, Thomas JL, et al: Mild traumatic brain injury in US soldiers returning from Iraq. N Engl J Med 2008; 358:453–463
17.
Polusny MA, Kehle SM, Nelson NW, et al: Longitudinal effects of mild traumatic brain injury and posttraumatic stress disorder comorbidity on postdeployment outcomes in National Guard soldiers deployed to Iraq. Arch Gen Psychiatry 2011; 68:79–89
18.
Schneiderman AI, Braver ER, Kang HK: Understanding sequelae of injury mechanisms and mild traumatic brain injury incurred during the conflicts in Iraq and Afghanistan: persistent postconcussive symptoms and posttraumatic stress disorder. Am J Epidemiol 2008; 167:1446–1452
19.
Lange RT, Brickell T, French LM, et al: Risk factors for postconcussion symptom reporting after traumatic brain injury in US military service members. J Neurotrauma 2013; 30:237–246
20.
Pietrzak RH, Johnson DC, Goldstein MB, et al: Posttraumatic stress disorder mediates the relationship between mild traumatic brain injury and health and psychosocial functioning in veterans of Operations Enduring Freedom and Iraqi Freedom. J Nerv Ment Dis 2009; 197:748–753
21.
Cassidy JD, Cancelliere C, Carroll LJ, et al: Systematic review of self-reported prognosis in adults after mild traumatic brain injury: results of the International Collaboration on Mild Traumatic Brain Injury Prognosis. Arch Phys Med Rehabil 2014; 95(suppl):S132–S151
22.
Dismuke CE, Walker RJ, Egede LE: Utilization and cost of health services in individuals with traumatic brain injury. Glob J Health Sci 2015; 7:156–169
23.
Vanderploeg RD, Belanger HG, Curtiss G: Mild traumatic brain injury and posttraumatic stress disorder and their associations with health symptoms. Arch Phys Med Rehabil 2009; 90:1084–1093
24.
Larson EB, Kondiles BR, Starr CR, et al: Postconcussive complaints, cognition, symptom attribution and effort among veterans. J Int Neuropsychol Soc 2013; 19:88–95
25.
Belanger HG, Barwick FH, Kip KE, et al: Postconcussive symptom complaints and potentially malleable positive predictors. Clin Neuropsychol 2013; 27:343–355
26.
Mittenberg W, DiGiulio DV, Perrin S, et al: Symptoms following mild head injury: expectation as aetiology. J Neurol Neurosurg Psychiatry 1992; 55:200–204
27.
Hardy M, Kennedy J, Reid M, et al: Differences in posttraumatic stress disorder, depression, and attribution of symptoms in service members with combat versus noncombat mild traumatic brain injury. J Head Trauma Rehabil (Epub ahead of print, April 25, 2019)
28.
Neurobehavioral Symptom Inventory (NSI): Recommendations for Scoring and Serial Administration for Concussion Health Care Outcomes Standardization. Washington, DC, Department of the Army, 2014
29.
Vanderploeg RD, Silva MA, Soble JR, et al: The structure of postconcussion symptoms on the Neurobehavioral Symptom Inventory: a comparison of alternative models. J Head Trauma Rehabil 2015; 30:1–11
30.
Meterko M, Baker E, Stolzmann KL, et al: Psychometric assessment of the Neurobehavioral Symptom Inventory–22: the structure of persistent postconcussive symptoms following deployment-related mild traumatic brain injury among veterans. J Head Trauma Rehabil 2012; 27:55–62
31.
Wickwire EM, Williams SG, Roth T, et al: Sleep, sleep disorders, and mild traumatic brain injury—what we know and what we need to know: findings from a national working group. Neurotherapeutics 2016; 13:403–417
32.
Martindale SL, Morissette SB, Rowland JA, et al: Sleep quality affects cognitive functioning in returning combat veterans beyond combat exposure, PTSD, and mild TBI history. Neuropsychology 2017; 31:93–104
33.
Finn JA, Lamberty GJ, Tang X, et al: Postrehabilitation mental health treatment utilization in veterans with traumatic brain injury: a VA TBI model systems study. J Head Trauma Rehabil 2018; 33:E1–E9
34.
Hebert JR, Forster JE, Stearns-Yoder KA, et al: Persistent symptoms and objectively measured balance performance among OEF/OIF veterans with remote mild traumatic brain injury. J Head Trauma Rehabil 2018; 33:403–411
Information & Authors
Information
Published In
History
Received: 12 September 2019
Revision received: 30 November 2019
Accepted: 10 December 2019
Published online: 14 February 2020
Published in print: Summer 2020
Keywords
Authors
Competing Interests
The authors report no financial relationships with commercial interests.
Metrics & Citations
Metrics
Citations
Export Citations
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.
For more information or tips please see 'Downloading to a citation manager' in the Help menu.
View Options
View options
PDF/EPUB
View PDF/EPUBLogin options
Already a subscriber? Access your subscription through your login credentials or your institution for full access to this article.
Personal login Institutional Login Open Athens loginNot a subscriber?
PsychiatryOnline subscription options offer access to the DSM-5-TR® library, books, journals, CME, and patient resources. This all-in-one virtual library provides psychiatrists and mental health professionals with key resources for diagnosis, treatment, research, and professional development.
Need more help? PsychiatryOnline Customer Service may be reached by emailing [email protected] or by calling 800-368-5777 (in the U.S.) or 703-907-7322 (outside the U.S.).