Mr. A, age 45, presents to the psychiatry clinic complaining of “ADHD.” He says he is not able to sit through movies and often gets distracted while on his computer at work. He also is having problems in his relationship with his wife; she says having a conversation with him is difficult. He has seen a psychiatrist for depression, which is currently managed by his primary care physician (PCP), who prescribed sertraline, 100 mg/d. Mr. A feels that although his depression is now under control, the medication has had limited effect on improving his concentration.
With further discussion, Mr. A reveals that 6 months ago he was involved in a car accident and suffered a mild traumatic brain injury (TBI). He was hospitalized overnight and was encouraged to follow up with his PCP. During his only follow-up visit, Mr. A told his PCP that he was having difficulty concentrating since the accident. However, because Mr. A has a remote history of alcohol abuse, his physician was reluctant to give him additional medication and referred him to a psychiatrist.
TBI is increasingly common but often overlooked or not treated in the emergency room (ER). Each year at least 1.7 million people experience a TBI; 275,000 are hospitalized and 52,000 die.1 The true incidence likely is greater because patients who do not present to the ER or hospital are not included in most studies, and the often-subtle psychiatric sequelae may preclude patients from seeking mental health treatment.
Psychiatric disorders are common among those who sustain a TBI (Table 1).2 One prospective cohort study found that patients with mild TBI are 2.8 times more likely than other patients to develop a psychiatric disorder.3 Statistics regarding TBI and psychiatric illness often are limited because they rely on self-reports, chart review, or retrospective studies.4
TBI severity can be classified on the basis of Glasgow Coma Scale score and other factors (Table 2).5 The correlation between severity of injury and resulting psychiatric illness or post-concussive symptoms is unclear.6 There is evidence that cognitive defects are associated with decreased function. Cognitive dysfunction also has been associated with disability 10 years after moderate to severe TBI.7 The association between cognitive dysfunction and outcome is more strongly correlated with moderate to severe TBI; there is no clear association in mild TBI.7 Additionally, compared with patients with severe TBI, those with mild TBI were more likely to be employed. At all severity levels, function improves over time. Mild, moderate, and severe TBI have a similar recovery curve.7
Table 1
Psychiatric symptoms: Common among TBI patients
| Psychiatric symptom | Incidence |
|---|---|
| Aggression | 30% |
| Anxiety | 10% to 70% |
| Apathy | 10% |
| Cognitive impairment | 25% to 70% |
| Depression | 25% to 50% |
| Mania | 1% to 10% |
| Psychosis | 3% to 8% |
| TBI: traumatic brain injury | |
| Source: Adapted from reference 2 | |
Table 2
Classifying severity of traumatic brain injury
| Severity | GCS score | LOC duration | PTA* |
|---|---|---|---|
| Mild | 13 to 15 | <30 minutes | <1 hour |
| Moderate | 9 to 12 | 1 to 24 hours | 1 to 24 hours |
| Severe | <8 | >24 hours | >24 hours |
| *Includes loss of memory immediately before or after the accident | |||
| GCS: Glasgow Coma Scale; LOC: loss of consciousness; PTA: posttraumatic amnesia | |||
| Source: Reference 5 | |||
Cognitive dysfunction and TBI
Cognitive dysfunction can be split into 3 categories:
- executive function
- memory
- processing speed.
The incidence of cognitive dysfunction after TBI is unclear. Several methods are used to quantify cognitive dysfunction in TBI patients; it is widely regarded that the Mini-Mental State Exam is not adequate to screen for subtle cognitive deficits.6 However, there is no clear consensus on which tool should be used.5
Off-label pharmacotherapy
There are no FDA-approved medications for treating neuropsychiatric sequelae of TBI. Treatment should be symptom-based and employ the “start low, go slow” approach. Compared with patients without brain injury, TBI patients may experience increased adverse effects from psychotropics but may require standard doses. These patients also may have comorbidities such as seizure disorders, substance abuse, and depression that will affect treatment.2 Different areas of cognitive function respond to different medication classes. Suggested medications include stimulant and nonstimulant catecholaminergic agents and cholinesterase inhibitors (Table 3).8
Executive function responds to non-stimulant catecholaminergics. In a review, Writer and Schillerstrom5 found that TBI patients who received catecholaminergic augmentation showed improved function in 6 of 7 studies. In 2 randomized controlled trials (RCTs) and 4 nonrandomized, placebo-controlled trials, patients with mild to severe TBI showed improved executive function, attention, global cognitive function, memory, language, and/ or arousal with use of bromocriptine, pramipexole, carbidopa/levodopa, or amantadine.5 The greatest improvements were found in executive function. In 1 RCT, 10 patients with mild to severe TBI showed no functional improvement after 2 weeks of treatment.