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PSYCHIATRIC OUTCOMES

Psychiatric disorders after traumatic brain injury (TBI) have been well documented. Rogers and Read (2007) note that survivors of brain injury are at particularly increased risk for depression, generalized anxiety disorder, and posttraumatic stress disorder (PTSD), although the etiology is unclear. They further note that psychiatric sequelae are often among the most disabling consequences of a TBI and can adversely affect recovery and psychosocial outcome.


As advances in neuroscience have begun to elucidate the pathophysiology of psychiatric disorders, there is progress toward delineating the specific regional brain structures, functions, and chemistry underlying the conditions (Drevets, 2001; Rauch et al., 2006). The Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV), which is considered the gold standard for psychiatric diagnosis, explicitly distinguishes between psychiatric disorders that emerge in a primary fashion (for example, major depressive disorder) and those attributable to a specific medical cause, such as an endocrine disturbance, stroke, or TBI (for example, mood disorder due to a general medical condition).


Taylor and Jung (1998) postulate that a person’s decreased ability to function at work and at home after a TBI leads to psychologic distress that in turn leads to the development of mood disorders with greater frequency than in the general population. In such cases of nonspecific effects of psychologic stress, a primary psychiatric diagnosis in accordance with DSM-IV would be appropriate. In contrast, if the psychiatric condition were deemed to be a direct consequence of the TBI because of disruption of brain function—for example, as is believed to occur when stroke affects specific brain distributions (Spalletta et al., 2006)—the diagnosis of mood disorder due to a general medical condition might be more appropriate. In addition to the possibility that TBI leads to psychiatric sequelae through nonspecific psychologic factors or through more specific brain injury–related factors, there is evidence that prior psychiatric illness may predispose to TBI, which in turn could increase the risk of recurrence or exacerbation of previous psychiatric conditions (Fann et al., 2002). Thus, given the uncertainty regarding the mechanisms that link TBI and psychiatric diagnoses, we have chosen to use the terminology of primary psychiatric disorders, as has been the custom in the TBI literature on psychiatric outcomes.


The committee reviewed approximately 350 studies of mood and anxiety disorders and other psychiatric outcomes after brain injury. Few studies, however, met the committee’s criteria for a primary study.



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8 PSYCHIATRIC OUTCOMES Psychiatric disorders after traumatic brain injury (TBI) have been well documented. Rogers and Read (2007) note that survivors of brain injury are at particularly increased risk for depression, generalized anxiety disorder, and posttraumatic stress disorder (PTSD), although the etiology is unclear. They further note that psychiatric sequelae are often among the most disabling consequences of a TBI and can adversely affect recovery and psychosocial outcome. As advances in neuroscience have begun to elucidate the pathophysiology of psychiatric disorders, there is progress toward delineating the specific regional brain structures, functions, and chemistry underlying the conditions (Drevets, 2001; Rauch et al., 2006). The Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV), which is considered the gold standard for psychiatric diagnosis, explicitly distinguishes between psychiatric disorders that emerge in a primary fashion (for example, major depressive disorder) and those attributable to a specific medical cause, such as an endocrine disturbance, stroke, or TBI (for example, mood disorder due to a general medical condition). Taylor and Jung (1998) postulate that a person’s decreased ability to function at work and at home after a TBI leads to psychologic distress that in turn leads to the development of mood disorders with greater frequency than in the general population. In such cases of nonspecific effects of psychologic stress, a primary psychiatric diagnosis in accordance with DSM-IV would be appropriate. In contrast, if the psychiatric condition were deemed to be a direct consequence of the TBI because of disruption of brain function—for example, as is believed to occur when stroke affects specific brain distributions (Spalletta et al., 2006)—the diagnosis of mood disorder due to a general medical condition might be more appropriate. In addition to the possibility that TBI leads to psychiatric sequelae through nonspecific psychologic factors or through more specific brain injury–related factors, there is evidence that prior psychiatric illness may predispose to TBI, which in turn could increase the risk of recurrence or exacerbation of previous psychiatric conditions (Fann et al., 2002). Thus, given the uncertainty regarding the mechanisms that link TBI and psychiatric diagnoses, we have chosen to use the terminology of primary psychiatric disorders, as has been the custom in the TBI literature on psychiatric outcomes. The committee reviewed approximately 350 studies of mood and anxiety disorders and other psychiatric outcomes after brain injury. Few studies, however, met the committee’s criteria for a primary study. 265

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266 GULF WAR AND HEALTH MOOD DISORDERS Mood disorders are a cluster of mental disorders that are characterized by mood swings or an abnormally depressed (low) or manic (elevated or irritable) mood. The most common mood disorder is major depression; others include bipolar disorder (or manic-depressive disorder), cyclothymia, and dysthymia (United States Department of Health and Human Services, 2006). Major depression is characterized by persistent feelings of sadness accompanied by several symptoms related to changes in appetite or sleeping patterns, loss of interest in activities, fatigue, inability to concentrate, and hopelessness or suicidal thoughts. Bipolar disorder is characterized by at least one manic episode and often by recurring episodes of mood disturbance, including both depressed and manic episodes. Bipolar disorder typically begins in a person’s middle twenties, tends to appear in families, and is a lifelong disorder. There are few published data on an association of TBI with bipolar disorder. Suicidal behavior is one of the most serious consequences of mood disorders and may consist of suicidal ideation (thoughts), suicide attempts, or completed suicide; suicide is discussed in the next section of this chapter. Primary Studies The committee identified four primary studies that examined an association between TBI and mood disorders. Fann et al. (2004) conducted a prospective cohort study to determine the risk of psychiatric illness after TBI. Patients were drawn from a health maintenance organization, Group Health Cooperative of Puget Sound, and received care in its facilities in six different counties in Washington. Computerized records of 939 health-plan members, 15 years old or older who had a diagnosis of a TBI in 1993, were available. Each patient was matched on sex, age, and reference date to three randomly selected unexposed health-plan members. TBI was ascertained in an emergency room, hospital or outpatient clinic, and severity of TBI was established by using the Centers for Disease Control and Prevention criteria. Psychiatric illnesses were ascertained by using the presence of psychiatric diagnoses, filling of prescriptions for psychiatric medications, and utilization of psychiatric services. In the first year after a moderate to severe TBI, 49% of the patients had evidence of psychiatric illnesses compared with 34% in the mild-TBI group and 18% in the comparison group; this reflected a significantly increasing risk of psychiatric illness with severity of TBI. The authors also found the risk of psychiatric illness to be greatest in the 6–12 months after the TBI in analyses that separately considered whether or not psychiatric illness had occurred in the year before injury. In patients without psychiatric illness in the year before injury, there was a 4-fold increased risk for developing a psychiatric disorder in the 6 months after a moderate to severe TBI (95% confidence interval [CI], 2.4–6.8) and a 2.8-fold increased risk after a mild TBI (95% CI, 2.1–3.7) compared with the risk in patients without a TBI. In patients with prior psychiatric illness, the corresponding increases in risk of psychiatric illness were factors of 2.1 (95% CI, 1.3–3.3) and 1.6 (95% CI, 1.2–2.2), respectively. The limitations of the study include the possible lack of precision in TBI exposure measurement, uncertainty regarding past psychiatric diagnosis occurring more than 1 year before ascertainment, and possible confounding by socioeconomic status. Holsinger et al. (2002) examined the association between TBI and lifetime and current depression in a nested case–control study of World War II veterans. Cases were World War II veterans who had been hospitalized for TBI in 1944–1945 and controls were veterans who had been hospitalized during the same period with either pneumonia or serious laceration or other

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PSYCHIATRIC OUTCOMES 267 wounds but without TBI. Veterans were identified 50 years after the war on the basis of the diagnosis reported on their “F-cards” in their medical records. Of the 3,460 veterans with reported head injuries (combat and non-combat-related), 1,422 met the authors’ criteria for TBI—documented TBI in a military record; occurrence during military service; produced loss of consciousness (LOC), posttraumatic amnesia (PTA), or nondepressed skull facture; failure to penetrate the dura mater; and lack of significant cognitive impairment or neurological sequelae more than 3 months after the trauma—and 520 were included in the study. TBI was categorized as mild, moderate, or severe on the basis of the duration of LOC or PTA. Motor- vehicle crashes (26%), falls (19%), and blast concussions (17%) were the leading causes of head injuries. Among the 4,022 potential controls, 1,198 were included in the study. A lifetime history of depression was assessed on the basis of a structured telephone interview with the veteran or his proxy; participants who responded affirmatively to any of three questions regarding mood also were given a modified version of the Diagnostic Interview Schedule for depression to decide on a DSM-IV diagnosis of major depression. The lifetime odds of major depression was significantly increased in veterans with TBI compared with controls (odds ratio [OR], 1.54, 95% CI, 1.17–2.04). Current major depression was also significantly increased in veterans with TBI (OR, 1.63, 95% CI, 1.07–2.50). The odds of lifetime depression also varied with TBI severity with ORs of 1.99 (95% CI, 1.11–3.57) for severe TBI, 1.40 (95% CI, 0.97–1.83) for moderate TBI, and 1.49 (95% CI, 0.96–2.31) for mild TBI. Alcohol abuse, myocardial infarction, and cerebrovascular accident did not appear to influence the association between TBI and lifetime risk of major depression. However, the odds did increase with age: ORs were 0.81 (95% CI, 0.45–1.43) for men aged 65–69 years old, 1.45 (95% CI, 1.07–1.97) for men 70–74 years old, 2.61 (95% CI, 1.58–4.30) for men 75–79 years old, and 5.95 (95% CI, 2.05–17.23) for men 80 years old and older. One important limitation of this study was the failure to specifically ascertain the presence of major depression before TBI. Jorge et al. (2004) assessed the presence of comorbid psychiatric disorders in 91 consecutive patients with closed TBI and a comparison group of 27 patients with multiple trauma but without evidence of central nervous system injury who were admitted at injury to two Iowa medical facilities. Patients with peripheral nerve injuries or spinal-cord injuries were excluded. All included patients were assessed at 3, 6, and 12 months after injury. A modified version of the Present State Examination and the Structured Clinical Interview for DSM-IV diagnoses were used to make a DSM-IV diagnosis of mood and anxiety disorder. The severity of symptoms of depression and anxiety was assessed with the Hamilton Depression Rating Scale and the Hamilton Anxiety Scale; aggressive behavior was assessed with the Overt Aggression Scale. Neuroimaging was done with computed tomography scans or magnetic resonance imaging, and a neuropsychologic assessment was conducted at 3 months. Of the 91 TBI patients, 47 (51.6%) developed a mood disorder in the 12 months after their injury, 30 (33%) of whom had major depressive disorder. There was no significant between-group difference with respect to prior history of depression or anxiety disorders. Mood disorder was statistically significantly more common in the TBI group than in the comparison group during the first year after injury (51.6% vs 22.2%, p = 0.006). Of the patients who met DSM-IV criteria for mood disorder, 30 of the TBI patients presented with major depression compared with controls (p = 0.008). The authors compared the 30 TBI patients who had major depressive disorder with the 44 TBI patients who did not develop any mood disorder in the 12 months after injury. Of the 30 TBI patients with major depression, 23 (76.7%) also met the criteria for an anxiety disorder compared

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268 GULF WAR AND HEALTH with 9 (20.5%) of the 44 TBI patients without major depression (p < 0.001). Of the 23 patients with both major depression and an anxiety disorder, 14 had generalized anxiety features, 2 had generalized anxiety and panic attacks, and 7 met the criteria for PTSD. Significant aggressive behavior was seen in 17 (56.7%) of the 30 patients with TBI and major depression compared with 10 (22.7%) of the 44 TBI controls (p = 0.003). Half the 30 patients with TBI and major depression received the diagnosis at their initial evaluation, and an additional 9 patients received the diagnosis at the 3-month follow-up. There were no significant differences between TBI patients with and without major depression in demographic variables or the use of alcohol or other drugs. Those with TBI and major depression had a significantly higher frequency of a personal history of mood disorders (p = 0.01) and anxiety disorders (p = 0.05). A recent study by Hoge et al. (2008) examined consequences of mild TBI in US soldiers that saw a high level of combat during a year-long deployment in Iraq. About 3–4 months after return from Iraq, soldiers were sent a questionnaire covering injury, combat intensity, physical symptoms, major depression, and PTSD. Soldiers were considered to have mild TBI if they answered yes to any of three questions—about losing consciousness, being dazed or confused, or not recalling the injury. The answers to those questions were used to form two subgroups within the mild-TBI group to determine whether LOC was a stronger predictor (that is, one that had LOC and one that had dazing or confusion or did not recall the injury—the second made up the altered-mental-status group). The final samples were 124 with mild TBI and LOC, 260 with mild TBI and altered mental status, 435 with other injury, and 1,706 with no injury. PTSD was present in 43.9% with LOC, in 27.3% with altered mental status, in 16.2% with other injury, and 9.1% without injury (p < 0.001). Major depression was associated with LOC more than with other injury (22.9% vs 6.6%, p < 0.001) but was not associated with altered mental status more than with other injury (8.4% vs 6.6%, p = 0.39). Limitations of this study included a failure to control analyses for major depression before TBI. Furthermore, groups were not well matched for combat intensity. Finally, it is unclear how one could effectively distinguish between a history of LOC or altered mental status attributable to TBI and similar phenomena attributable to dissociation 4 in the face of emotional trauma. Secondary Studies The committee identified five secondary studies that looked at the association between TBI and mood disorders, specifically, depression. Limitations of these studies include the self- reported diagnosis of TBI and retrospective assessment of mood disorders. Vanderploeg et al. (2007) conducted a cross-sectional study of the long-term psychiatric, neurologic, and psychosocial outcomes associated with self-reported mild TBI. A subsample of 4,384 veterans was categorized into three groups: no motor-vehicle accident and no TBI (normal control, n = 3,214); injured in a motor-vehicle accident but no TBI (motor-vehicle accident control; n = 539); and TBI with altered consciousness (mild-TBI group; n = 254). Results indicate that the mild-TBI group had a higher frequency of depression than the normal control group (OR, 1.77, 95% CI, 1.13–2.78). The mild-TBI group also had a higher frequency of prior depression than the normal control group, but the adjusted OR was virtually identical (1.78; 95% 4 Dissociation is a mental state in which a person’s thoughts, emotions, or memories are compartmentalized, usually in response to a traumatic event. Some dissociative disorders include psychogenic amnesia, psychogenic fugue, and multiple personality.

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PSYCHIATRIC OUTCOMES 269 CI, 1.06–3.00) when the analysis was restricted to those who had no prior history of depression. Three other secondary studies also found that depression was associated with TBI (Masson et al., 1996; Hibbard et al., 1998, Deb et al., 1999). In contrast, Malec et al. (2007) examined 51 patients who had moderate to severe TBI, 42 patients who had mild TBI, and 42 controls who had orthopedic injuries and found no difference in depression rates among the three groups. Summary and Conclusion The committee reviewed four primary and five secondary studies of mood disorders— major depression—and findings were consistent. The preponderance of studies found that groups with TBI (mild, moderate, or severe) had higher rates of major depression 6 months or longer after TBI than did appropriate comparison groups (including non-TBI injured controls). Three studies (Fann et al., 2004; Jorge et al., 2004; Vanderploeg et al., 2007) provided some control for differences in depression before TBI; all three provided data suggesting that the observed association between TBI and major depression could not be explained by prior depression. Nevertheless, it should be noted that the available data suggest that prior mood disorder may predispose to TBI (Fann et al., 2002; Vassallo et al., 2007) and that post-TBI major depression is more frequent in people who had major depression before TBI than in people who did not (Fann et al., 2004). In contrast to depression, there are few studies on the relationship between mania or bipolar disorder and TBI (Koponen et al., 2002; Sagduyu, 2002; Silver et al., 2001). Koponen et al. (2002) and Silver et al. (2001) reported a prevalence rate of 1.7% and 1.6%, respectively, of TBI patients who met criteria for bipolar disorder. They concluded that the prevalence did not differ significantly from that found in control populations. Sagduyu (2002) examined 535 patients who had bipolar disorder. Of the 126 patients who reported a history of mild TBI, 72 reported symptoms of bipolar disorder prior before the injury, and 54 reported symptoms after the injury. Those studies do not provide consistent or compelling evidence regarding an association between TBI and mania or bipolar disorder. The committee concludes, on the basis of its evaluation, that there is sufficient evidence of an association between TBI and depression. The committee concludes, on the basis of its evaluation, that there is inadequate/insufficient evidence to determine whether an association exists between TBI and mania or bipolar disorder.

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270 TABLE 8.1 Psychologic Outcomes—Mood-Disorder Studies Health Outcomes or Outcome Comments or Limitations Reference Study Design Population Type of TBI Measures Results Adjustments Fann et al., Prospective 939 HMO enrollees Severity Psychiatric illness Increased rates of Age, sex, TBI Limitation: control 2004 cohort (479 women, 460 dichotomized determined with psychiatric illness in reference date, group is general HMO men) with diagnosis with CDC three major year after TBI (49% logarithm of population, not an of TBI in 1993 categorization indicators: ICD-9- in moderate to costs in year injury population enrolled in health criteria into mild CM codes, severe, 34% in mild, before reference plan for at least 1 (803), moderate prescriptions, use of 18% in non-TBI date, comorbid year before injury, 3 to severe (136); psychiatric service comparisons) injuries to 1 match with injury identified year before TBI, 1– health-plan controls; with ICD-9-CM 12, 13–24, 25–36 TBI associated with cases, controls categories, codes mo after injury; higher risk of any followed for 3 years (fracture of vault affective disorders psychiatric illness 6 after enrollment in base of skull; included depression, mo after trauma in study other, anxiety subjects with or unqualified, without prior multiple psychiatric illness fractures of skull; No prior psychiatric intracranial illness (p < 0.001): injury) mild TBI, RR, 2.8 (95% CI, 2.1–3.7); moderate to severe TBI, RR, 4.0 (95% CI, 2.4–6.8) Prior psychiatric illness (p , 0.005): mild TBI, RR, 1.6 (95% CI, 1.2–2.0); moderate to severe TBI, RR, 2.1 (95% CI, 1.3–3.3) Subjects with mild TBI showed chronic likelihood of psychiatric illness

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Health Outcomes Comments or or Outcome Reference Study Design Population Type of TBI Measures Results Adjustments Limitations even in absence of prior psychiatric problems Affective disorders fairly common in TBI group with no prior psychiatric illness, particularly in persons who had mild TBI 1–6 mo: mild TBI, RR, 2.7 (95% CI, 1.5–4.8); moderate to severe TBI, RR, 1.0 (95% CI, 0.1– 7.6) 7–12 mo: mild TBI, RR, 2.2 (95% CI, 1.4–3.6); moderate to severe TBI, RR, 4.6 (95% CI, 1.8– 11.7) 13–18 mo: mild TBI, RR, 1.9 (95% CI, 1.3–2.6); moderate to severe TBI, RR, 2.2 (95% CI, 1.0– 4.9) 19–24 mo: mild TBI, RR, 1.6 (95% CI, 1.2–2.1); moderate 271 to severe TBI, RR,

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272 Health Outcomes Comments or or Outcome Reference Study Design Population Type of TBI Measures Results Adjustments Limitations 1.1 (95% CI, 0.4– 3.0) Holsinger et Population- 520 head-injured Closed head Depressive illness Lifetime prevalence Age, education, Only male veterans al., 2002 based male veterans who injuries: mild, ascertained of depression: history of alcohol used in study; limited retrospective were hospitalized moderate, severe withmodified DIS Head-injured, abuse, information on age at cohort for head injury, that (1) was for DSM-IV 18.5%; non-head- myocardial onset of depression, 1,198 non-head- documented in injured, infraction, but it is unlikely that injured WWII male military medical 13.4%; OR, 1.54 cerebrovascular there was history of veterans records; (2) (95% CI, 1.17–2.04) accident major depression at hospitalized with occurred during time of enlistment pneumonia or military service; Lifetime risk of laceration, puncture, (3) produced depression increased Excluded penetrating or incision wounds; LOC, PTA, or with severity of head TBI all were on active nondepressed injury: severe, OR, duty during 1944– skull fracture; 1.99 (95% CI, 1.11– 1945 in Navy or (4) did not 3.57); moderate, OR, Marine Corps and penetrate dura 1.40 (95% CI, 0.97– were followed at 50 mater; (5) did 2.03); mild, OR, 1.49 years after injury not result in (95% CI, 0.96–2.31) significant cognitive impairment or neurologic sequelae 3 mo after injury Head-injury severity: mild, LOC or PTA for <30 min; moderate, LOC or PTA 30 min– 24 h and/or skull fracture; severe, LOC or PTA 24 h or more

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Health Outcomes Comments or or Outcome Reference Study Design Population Type of TBI Measures Results Adjustments Limitations Sources of head injuries: MVA (26%), blast concussion (17%), fights with peers (7%), falls (19%), sports injuries, including boxing (12%), miscellaneous other wartime happenings (19%) Jorge et al., Cohort 91 consecutive Closed head Major depression Mood disorders, None 2004 patients with TBI injury (mild, associated with major depressive but without spinal- moderate, anxiety symptoms, disorders cord injury severe) Present State significantly more compared with 27 Examination, SCID frequent in TBI injured patients Severe TBI: clinical, patients than in without TBI also GCS, 3–8; neuropsychologic, patients without consecutively moderate TBI: brain-imaging brain injuries: after admitted into two GCS 9–12 or variables TBI, 47 (51.6%) university hospitals GCS 13–15 with developed mood and followed up at intracranial disorder compared 3, 6, 12 mo after surgical with six controls trauma procedures or (22.2%) group (p, focal lesions 0.006); major greater than 15 depressive disorder mL; mild TBI: occurred in 30 TBI GCS 13–15 patients (33%) vs without surgery two non-TBI injured or major focal (7.4%) (p, 0.008) lesions History of past 273

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274 Health Outcomes Comments or or Outcome Reference Study Design Population Type of TBI Measures Results Adjustments Limitations depression more common in patients with TBI and depression than in those with other injury and depression (36.7% vs 11.4%; p < 0.01); similarly, history of past anxiety more common in patients with TBI and depression than in those with other injury and depression (20% vs 4.6%; p < 0.05) Major depression significantly associated with comorbid anxiety disorder (76.7% vs 20.4%; p < 0.001) and decreased frontal brain volume and left frontal gray matter in first year after injury Hoge et al., Cohort Anonymous survey Mild PTSD Of 124 with LOC, 95% males; After adjustment for 2008 of 4,618 soldiers, of 43.9% met criteria 55.5% under 30 PTSD and depression, whom 2,714 (59%) 124 (4.9%) with for PTSD compared years old; 47.5% mild TBI no longer completed LOC with 27.3% of those junior enlisted significantly associated questionnaire; of reporting altered rank with physical health 2,714, 149 excluded 260 (10.3%) mental status, 16.2% outcomes or symptoms because of missing with altered with injuries, and except headache data, 40 because mental status 9.1% with no injury

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Health Outcomes Comments or or Outcome Reference Study Design Population Type of TBI Measures Results Adjustments Limitations they had head injury (such as dazed Soldiers with mild without LOC or confused) TBI and LOC more likely to report poor Remaining 2,525 435 (17.2%) general health, US Army soldiers with other missed workdays, responded 3–4 mo injuries more doctor visits, after return from 1- higher numbers of year Iraqi outcomes or deployment symptoms NOTE: CDC = Centers for Disease Control and Prevention, CI = confidence interval, DIS = Diagnostic Interview Schedule, DSM-IV = Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, GCS = Glasgow Coma Scale, HMO = health-maintenance organization, ICD-9-CM = International Classification of Diseases, Ninth Revision, Clinical Modification, LOC = loss of consciousness, PTA = posttraumatic amnesia, SCID = Structured Clinical Interview for DSM-IV diagnoses, TBI = traumatic brain injury, WWII = World War II. 275

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290 GULF WAR AND HEALTH respectively. When the subpopulation of each group that contracted their injury through fighting was examined, the corresponding percentages were 34% and 28%, 17%, and 15%, 1% and 6%, respectively—increased percentages of adverse outcomes in the TBI groups and an attenuation of the TBI effect in each “fighting” subgroup. Overall, TBI increased the risk of behavioral discharge 4 times and of criminal conviction 5 times compared with the normal group; it increased the risk of postinjury adverse action by 1.3 times and decreased the risk of medical discharge by 0.64 times compared with the orthopedic-injury group. “Adverse actions” increased in both the TBI and orthopedic-injury groups 1.75–3 times, but they increased more in the TBI group (3.0 times) than in the orthopedic-injury group (2.1 times). The differences between outcomes in the TBI (fighting) and the orthopedic-injury (fighting) subgroups were not statistically significant. The results of the study suggest that any person sustaining a TBI has a higher risk of later aggressive-behavior problems. Because the outcome measures in the study selected the more severe cases of behavioral impairment, the results may show only the peak of the full problem. Premorbid problems (such as fighting) are a risk factor for postinjury behavioral problems but did not produce worse outcomes in the TBI than in the orthopedic- injury group. In another primary study, Tateno et al. (2003) assessed aggressive behaviors in 89 TBI cases and 26 multiple-trauma cases (without TBI) consecutively admitted into two Iowa hospitals. Severity of brain injury was measured according to the GCS and PTA and classified with the TCDB. Aggressivity was assessed with the Overt Aggression Scale (OAS) and premorbid aggressive behavior was estimated from premorbid police contact and legal actions. Psychiatric assessments were done by a psychiatrist using the PSE and the Structured Clinical Interview for DSM-IV, along with other standard psychiatric rating scales. Structural neuroimaging scans were also collected. Of the TBI group, 33.7% met the criteria for aggressive behavior in the 6 months after injury (called the aggressive group), compared with 11.5% of the non-TBI injured group; the remaining 66.3% of the TBI group showed low aggressive traits (the nonaggressive group). When the aggressive and nonaggressive TBI subjects were compared major depressive disorder was more frequent in the aggressive group (X2, 6.54; df, 1; p = 0.01), and the group had a higher Hamilton Depression Rating Score (t, -3.51; df, 87; p = 0.0007) and a higher Hamilton Anxiety Scale scores (t, -3.37; df, 87; p = 0.001). Focal frontal lobe lesions on a magnetic resonance scan occurred more frequently in the aggressive TBI group than in the nonaggressive group (X2, 8.05; df, 1; p = 0.005), whereas a more diffuse lesion was more frequent in the nonaggressive TBI group. Virkkunen et al. (1977) examined 1,830 Finnish World Ward II veterans who had received penetrating head injuries and 500 noninjured veteran controls; both groups were followed for up to 37 years. Of the TBI group, 33.1% sustained frontal, 19.5% temporal, 37.7% parietal, and 9.7% occipital lesions. Most veterans in both groups had lifelong employment, despite their injuries. Criminal convictions were no more common in the TBI veterans (5.5%) than in the veteran controls (4.2%), and crimes of violence were not more common in the TBI veterans (0.9%) than in the noninjured veteran group (0.6%). Crimes did not tend to be recurrent in either group. Secondary Study Grafman et al. (1996) studied aggression and violence in Vietnam veterans who had TBI and non-brain-injured Vietnam veterans to show that mediofrontal and orbitofrontal lesions of

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PSYCHIATRIC OUTCOMES 291 the prefrontal cortex are the ones associated with aggression and violence and especially with verbal confrontations. That demonstration of an association between a localized frontal lobe injury and TBI is especially important in light of the considerable literature documenting loss of inhibition and greater aggressive behavior after frontal lobe injury. They hypothesized that lesions to the prefrontal cortex impair the ability to sustain “managerial knowledge” and bias behavior away from plans and social rules toward aggressive and violent behavior. DRUG AND ALCOHOL ABUSE DISORDERS Secondary Studies Many studies have shown a relationship between drug and alcohol use and TBI, and it is generally accepted that drug and alcohol use precedes the TBI and increases the risk of head injury. Therefore, studies have examined post-TBI alcohol use only in the context of previous drug and alcohol use estimated as closely as possible. Horner et al. (2005) focused on the assessment of alcohol abuse and dependence (AA/D) in a 1-year period in a sample of 1,606 TBI patients, randomly sampled from a large state-wide sample of all TBI patients discharged from South Carolina hospitals in 1999–2002 and fully assessed at the time of the incident. A telephone interview a year after TBI was used to obtain information on alcohol use for the month preceding assessment. Overall, 15.4% were heavy drinkers, 14.3% moderate drinkers, and 70.3% infrequent drinkers or abstainers. Almost all interviewed (99.8%) reported drinking the same or less than a year before; half the current heavy and moderate drinkers were consuming less than they were a year before. Risk factors for heavy drinking were male sex, lower age, substance abuse before TBI, and a diagnosis of depression since TBI. Jorge et al. (2005) studied 158 Level I TBI patients of whom 24.1% were alcohol- dependent and 10.8% were alcohol abusers; alcohol use during the year before TBI was 34.8%. Of the 55 TBI patients with premorbid AA/D, 30 completed 1 year of followup and 60% of the group followed up resumed their alcohol use; of those 55, 60% developed a mood disorder during the post-TBI year compared with 36.9% of the non-AA/D group. Patients with pre- existing AA/D had reduced cerebral grey matter (GM) volumes compared with patients without AA/D, and post-TBI relapsers had even greater reductions in GM volumes. Moreover, vocational outcome was lower in those with AA/D, especially if it coexisted with mood disorders. Bombardier et al. (2003) followed a group of consecutively admitted TBI patients over the course of a year. They showed that drinking decreased considerably from before injury to 1 year after TBI: abstinence rates increased from 14% to 36%; people without substantial alcohol- related problems increased from 64% to 84%; and remission of substantial alcohol problems ranged from 30.8% to 56%. However, there was a subset of survivors (about 25%) who drank heavily at 1 year after TBI, and the level of pre-TBI alcohol use predicted who would be in the post-TBI heavy-drinking group. That suggests that drug and alcohol use should still be monitored after TBI.

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292 GULF WAR AND HEALTH PSYCHOTIC DISORDERS Primary Studies Fann et al. (2004) used the Group Health Cooperative (GHC) of Puget Sound (450,000 members) in a prospective cohort study of TBI. All GHC members with a new diagnosis of TBI in 1993 who had been GHC members for at least a year were examined, evaluated for severity and matched with randomly selected GHC non-TBI members by sex, age, and enrollment date. Psychiatric illness was assessed for the year preceding TBI and for the 3-year period after TBI, as noted by the presence of a psychiatric diagnosis, filling of a prescription for a psychiatric medication, or use of psychiatric services. Psychiatric diagnoses were made according to ICD-9- CM by primary-care physicians. The authors collected 939 cases of TBI in 1993, for an overall annual TBI incidence of 475.2 per 100,000 person-years; 85.5% of the TBIs were mild. The risk of psychiatric illness was significantly increased after mild and moderate-severe TBI. Increased ORs were observed especially in patients with no prior history of psychiatric illness, within the first year after TBI: the OR was 2.1 (95% CI, 1.6–2.6) in those with mild TBI and 3.4 (95% CI, 1.9–5.8) in those with moderate to severe TBI. An approximate 1.5-fold increase in risk of psychiatric illness was also observed in the following 3 years in patients who had a diagnosis of a psychiatric illness before sustaining a mild TBI; no association was observed in such patients who sustained a moderate to severe TBI. Specifically, the new onset of a psychotic disorder was no greater after mild TBI in the following 3 years than in the year before the TBI, whereas after moderate to severe TBI, a diagnosis of psychosis were greater but not until the second and third years: 1–12 months after TBI, the OR was 2.8 (not significant); 13–24 months after TBI the OR was 5.9 (95% CI, 1.6–22.1); and 25–36 months after TBI the OR was 3.6 (95% CI, 1.0–12.3). The OR for any psychiatric diagnosis during the 3-year followup was increased considerably if there was a prior psychiatric illness. Secondary Studies A study by Achte et al. (1969) also found an association between TBI and psychosis. Data were collected in a Finnish hospital for brain injuries that housed all central nervous system–injured war veterans of the 1939–1945 Finnish Wars; 3,552 men comprise this cohort followed for 22–26 years. About 42% had a penetrating head wounds (shell splinters and gun shot wounds), and 58% had closed TBI. In this population, 317 (8.9%) out of the 3,552 veterans had had a diagnosis of psychosis (a rate that is 2–3 times the usual population-based rate of approximately 3–4%). In addition, 30.4% had epilepsy (44.2% of those with penetrating head injuries and 20.3% of those with closed TBIs), and 8.9% had aphasias (16.1% of those with penetrating head injuries and 3.7% of those with closed TBIs). Godfrey et al. (1993), in a small but well-controlled study focusing on insight, found poor insight regarding behavioral impairment at 6 months after TBI. The defect appeared to attenuate with time. Increased insight regarding behavioral impairment was accompanied by emotional dysfunction. Henry et al. (2006) compared a group of TBI patients with their friends and close relativse for their ability to identify their own emotions (an aspect of insight) and found the TBI group impaired, less able to recognize emotion in others, externally oriented and less fluent on tests of semantic fluency.

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PSYCHIATRIC OUTCOMES 293 Summary and Conclusions Aggressive Behaviors The committee concludes, on the basis of its evaluation, that there is sufficient evidence of an association between TBI and subsequent development of aggressive behaviors. Additional evidence that aggression is associated with TBI primarily when frontal cortical lesions are sustained is consistent with a large literature associating frontal lobe damage with loss of behavioral control. Alcohol and Drug Abuse The committee concludes, on the basis of its evaluation, that there is limited/suggestive evidence of an association between TBI and decreased drug and alcohol use, as compared with preinjury levels, in the 1–3-year period following the TBI. Psychosis The committee concludes, on the basis of its evaluation, that there is limited/suggestive evidence of an association between moderate or severe TBI and psychosis. However, even if the TBI is severe, the psychosis does not appear during the first post-TBI year, but rather, becomes apparent in the second and third post- TBI years.

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294 TABLE 8.4 Psychologic Outcomes—Personality Disorder Studies Health Outcomes or Outcome Comments or Measures Limitations Reference Study Design Population Type of TBI Results Adjustments Fann et al., Prospective 939 HMO enrollees Mild (803), Psychiatric illness Increased rates Age, sex, TBI Possible 2004 cohort (479 women, 460 moderate to determined with of psychiatric reference date, misclassification of men) with diagnosed severe (136); three major illness in year logarithm of diagnoses; lack of TBI in 1993 enrolled injury indicators: ICD-9- after TBI (49% costs in year precision in in health plan for at identified with CM codes, in moderate to before TBI measurement of TBI least 1 year before ICD-9-CM prescriptions, severe, 34% in reference date, exposure injury, 3 to 1 match categories, psychiatric-service mild, 18% in comorbid injuries with health plan codes (fracture use in year before non-TBI Control group is controls; followed up of vault base of TBI, 1–12 mo, 13– comparisons) general HMO to 3 years after skull; other, 24 mo, 25–36 mo population, not injury enrollment in study unqualified, after injury TBI associated population multiple with higher fractures of risk of Had preinjury data skull; adjustment intracranial reaction in injury) year after TBI: mild, 7.2%; moderate to severe, 7.4%; controls, 4.6% TBI associated with higher risk of psychotic disorder in year after TBI: mild, 3.0%; moderate to severe, 13.0%; controls, 1.9% Ommaya et Retrospective 2,243 TBI military TBI severity Post-TBI Behavioral: Stratified by Alcohol use not al., 1996 cohort hospital patients determined discharge from mild TBI, whether injuries considered from discharge with ICD-9 to active-duty service OR, 1.8 (95% arose from fights records for all compute AIS for: behavioral CI, 1.4–2.2); Normal orthopedic military hospitals vs and ISS; mild reasons, criminal moderate TBI, controls

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Health Outcomes or Outcome Comments or Measures Reference Study Design Population Type of TBI Results Adjustments Limitations active-duty (1,778), conviction, alcohol NS; severe population moderate and drug abuse, TBI, (1,879,724), (174), severe medical disability, NS followed up 2.7 (274) death years after injury Alcohol, drug abuse: mild TBI, OR, 2.6 (95% CI, 1.6– 4.3); moderate TBI, OR, 5.4 (95% CI, 1.7– 16.9); severe TBI, NS Criminal conviction: mild TBI, OR 2.7 (95% CI, 1.9–3.9); moderate TBI, NS; severe TBI, NS Tateno et Retrospective 89 patients with TBI severity Aggressive 30 (33.7%) al., 2003 cohort closed head injury determined behavior assessed TBI patients admitted into with GCS, with Overt presented with University of Iowa Traumatic Aggression Scale; aggressive hospitals and clinics, Coma Data mood, anxiety behavior Iowa Methodist Bank; mild disorders assessed during first 6 Medical Center; 26 (50), moderate by psychiatrist mo compared patients with (19), severe with three multiple traumas but (19), 1 missing (11.5%) without brain controls (p < damage or spinal- 0.03) cord injury 295

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296 Health Outcomes or Outcome Comments or Measures Reference Study Design Population Type of TBI Results Adjustments Limitations Virkkunen Retrospective 1,830 Finnish Criminal 100 (5.5%) et al., 1977 cohort veterans of WWII convictions in TBI patients, with penetrating Finland collected 21 (4.2%) brain injuries, 500 from Criminal controls noninjured Finnish Register convicted of WWII veterans as crimes (NS) controls NOTE: AIS = Abbreviated Injury Scale, CI = confidence interval, GCS = Glasgow Coma Scale, HMO = health-maintenance organization, ICD-9-CM = International Classification of Diseases, Ninth Revision, Clinical Modification, ISS = Injury Severity Score, NS = not significant, OR = odds ratio, TBI = traumatic brain injury, WWII = World War II.

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