Pharmacotherapy and the neurobehavioural sequelae of traumatic brain injury

123I-Iofluopane Single-Photon Emission Computed Tomography as an Imaging Biomarker of Pre-Synaptic Dopaminergic System after Moderate-to-Severe Traumatic Brain Injury

Dopaminergic (DA) system function is frequently disrupted after traumatic brain injury (TBI). However, published interventions that target the DA system with the hope of enhancing functional outcomes are inconclusive, partially because of the lack of DA signaling biomarkers that can be used to select patients likely to benefit from DA-directed therapies or to monitor treatment efficacy. The aim of this study was to evaluate the feasibility of using ¹²³I-iofluopane single-photon emission computerized tomography (SPECT) to assess pre-synaptic DA system dysfunction after severe TBI. Eighteen patients with severe TBI were enrolled in this study. ¹²³I-iofluopane SPECT imaging was performed at baseline and again 2.5 h after a single dose of methylphenidate (MP) administered enterally. DA transporter (DAT) specific binding ratio (SBR) before and after MP was measured. Functional outcomes included the Disability Rating Scale, JFK Coma Recovery Scale-Revised, Functional Independence Measure, and Functional Assessment Measure. Thirteen of 18 patients completed the study. Average time from injury to SPECT scan was 48 days (standard deviation [SD], 24 days; median, 31). Baseline ioflupane striatal SBR was 1.51 ± 0.46 (median, 1.67). A 43.1% (SD, 16; median, 46.5) displacement of ioflupane from pre-synaptic DAT was observed after MP administration. Baseline SBR positively correlated with functional status at baseline and 4 weeks after completion of the study. Serum MP levels correlated with relative change in SBR (r_s = 0.60; p = 0.04). Our findings suggest that ¹²³I-iofluopane SPECT is a promising tool to determine the severity of pre-synaptic DA terminal disruption and for monitoring pharmacokinetics and pharmacodynamics of therapeutic interventions targeting the DA system.

Neurobehavioral Initiation and Motivation Problems After Acquired Brain Injury

Motivation is a primary and permanent source of human behavior and adaptation. Motivational deficits, along with deficiencies in initiation, frequently occur in individuals with acquired brain injury (ABI). These neurobehavioral problems are associated with consequences at the participation level: patients are reluctant to engage in rehabilitation, and their subsequent social reintegration is often at risk. The same problems may also become a heavy burden for the families of individuals with ABI. In the present paper, we will critically review both the current definitions and the instruments used to measure motivational disorders following ABI. We will also describe the neural system underlying motivation and its impairments. What emerges is the need to develop specific rehabilitative treatments, still absent at the moment, with the ultimate aim of ensuring a better quality of life for both the patients and their proxies.

The effectiveness of methylphenidate in improving cognition after brain injury in adults: a systematic review

Objective: To conduct a systematic review investigating the effectiveness of methylphenidate in improving cognition following brain injury in an adult population.Data sources: CINAHL, PsychINFO, MEDLINE, and PubMed databases were searched for all relevant articles published from January 1980 up to December 2017.Study selection: Studies were included if participants had a diagnosis of new onset or previous acquired brain injury and were age 16 or over. Studies must have administered methylphenidate and measured its effectiveness on cognition using at least one measure of cognitive function.Data extraction: Data extracted included study design, sample size, participant characteristics, intervention method, outcome measures, and findings. The quality of included randomized controlled trials was assessed using the Physiotherapy Evidence Database. An overall level of evidence was assigned using a modified Sackett scale.Data synthesis: Included studies consisted of seven randomized controlled trials, two pre-post trials, one prospective controlled trial, and one case study. All included studies reported improved cognitive abilities following methylphenidate treatment post-injury.Conclusions: There is the strongest level of evidence (Level 1a) suggesting methylphenidate may alleviate cognitive impairments in adults with brain injury. However, longitudinal studies are warranted examining the effectiveness and safety of long-term methylphenidate use in this population.

The manifestation of anxiety disorders after traumatic brain injury: a review

The development of anxiety disorders after a traumatic brain injury (TBI) is a strong predictor of social, personal, and work dysfunction; nevertheless, the emergence of anxiety has been largely unexplored and poorly understood in the context of TBI. This article provides an overview of the limited published research to date on anxiety disorders that are known to develop after TBI, including post-traumatic stress disorder, generalized anxiety disorder, obsessive-compulsive disorder, panic disorder, specific phobia, and social anxiety disorder. This review also examines diagnostic criteria, the epidemiology of each disorder, and the factors that influence the expression of these conditions, including injury-related and psychosocial variables. Putative neural correlates will be reviewed where known. A discussion of current treatment options and avenues for further research are explored.

Amantadine ameliorates dopamine-releasing deficits and behavioral deficits in rats after fluid percussion injury

Aims

To investigate the role of dopamine in cognitive and motor learning skill deficits after a traumatic brain injury (TBI), we investigated dopamine release and behavioral changes at a series of time points after fluid percussion injury, and explored the potential of amantadine hydrochloride as a chronic treatment to provide behavioral recovery.

Materials and Methods

In this study, we sequentially investigated dopamine release at the striatum and behavioral changes at 1, 2, 4, 6, and 8 weeks after fluid percussion injury. Rats subjected to 6-Pa cerebral cortical fluid percussion injury were treated by using subcutaneous infusion pumps filled with either saline (sham group) or amantadine hydrochloride, with a releasing rate of 3.6mg/kg/hour for 8 weeks. The dopamine-releasing conditions and metabolism were analyzed sequentially by fast scan cyclic voltammetry (FSCV) and high-pressure liquid chromatography (HPLC). Novel object recognition (NOR) and fixed-speed rotarod (FSRR) behavioral tests were used to determine treatment effects on cognitive and motor deficits after injury.

Results

Sequential dopamine-release deficits were revealed in 6-Pa-fluid-percussion cerebral cortical injured animals. The reuptake rate (tau value) of dopamine in injured animals was prolonged, but the tau value became close to the value for the control group after amantadine therapy. Cognitive and motor learning impairments were shown evidenced by the NOR and FSRR behavioral tests after injury. Chronic amantadine therapy reversed dopamine-release deficits, and behavioral impairment after fluid percussion injuries were ameliorated in the rats treated by using amantadine-pumping infusion.

Conclusion

Chronic treatment with amantadine hydrochloride can ameliorate dopamine-release deficits as well as cognitive and motor deficits caused by cerebral fluid-percussion injury.

Stimulant Use in Paediatric Acquired: Brain Injury: Evaluation of a Protocol

Children with acquired brain injury (ABI) experience deficits in attentional skills such as, sustained attention, distractability and impulsivity, which have the potential to influence all aspects of their functioning. The use of central nervous system (CNS) stimulants is gaining increasing popularity in adult ABI literature. CNS stimulants have been successfully utilised in the management of attentional problems in attention deficit-hyperactivity disorder and are believed to have their therapeutic effect by modulating neurotransmitter function in the neocortex, an area of the brain implicated in the neurobehavioural sequelae of ABI. Research into the use of CNS stimulants in paediatric ABI reports contradictory findings. We present the case of LI a 7-year-old boy with a history of ABI who underwent a trial of stimulant medication for management of attentional deficits. The case is discussed with regard to the efficacy of the pharmacological intervention and the design of objective protocols for stimulant trials.

Efficacy and safety of dopamine agonists in traumatic brain injury: a systematic review of randomized controlled trials

In the intensive care unit, dopamine agonists (DA) have been used in traumatic brain injury (TBI) patients to augment or accelerate cognitive recovery and rehabilitation. However, the efficacy and safety of DA in this population is not well established. We conducted a systematic review of randomized controlled trials (RCTs) examining the clinical efficacy and safety of DA in patients with TBI. We searched MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials, comparing DA to either placebo, standard treatment, or another active comparator. There was no restriction for age, date, or language of publication. Sensitivity analyses were planned to evaluate the potential effect of timing of TBI, age, drugs, and year of publication on efficacy. Among the 790 citations identified, 20 RCTs evaluating methylphenidate, amantadine, and bromocriptine were eligible. Significant clinical heterogeneity was observed between and within studies, which precluded any pooling of data. Efficacy outcomes included mainly neuropsychological measures of cognitive functioning. A total of 76 different neuropsychological tests were used, but most of them (59%) only once. Only 5 studies systematically assessed safety. No trend could be drawn from the analysis of efficacy and safety. Important sources of bias in the studies were of major concern. Considering the absence of consensus regarding clinical outcome, the lack of safety assessment, and the high risk of bias in the included trials, more research is warranted before DA can be recommended in critically ill TBI patients.

Pharmacotherapy for traumatic brain injury: focus on sympathomimetics

Traumatic brain injury (TBI) is a devastating neurological injury with broad manifestations. Unfortunately, its diagnosis and efficacious treatments remain elusive. Different post injury symptoms are exhibited at different time frames, indicative of a time-related progression of the pathology. Therefore, particular treatments must be tailored to the post injury time frame. This overview is focused on the secondary chronic phase following TBI and the value of sympathomimetic therapy during this phase. The various direct- and indirect-acting drugs are reviewed, and the treatment protocol employed by the author is described.

Advances in neuropharmacological rehabilitation for brain dysfunction

The use of pharmacological agents as rehabilitative tools following brain injury remains to some degree both a science and an art. Recent work in the area of the neural sciences has shed new light on the workings of basic CNS neurochemical systems and the use of pharmacologic agents in altering central neurophysiologic processes. The major central neurochemical systems are reviewed both anatomically and physiologically. An overview is provided of basic neuropharmacologic agents by class. Lastly, some of the newer neuropharmacological options for treatment of post-acute brain injury deficits are examined.

Classifying psychiatric disorders after traumatic brain injury and orthopaedic injury in children: adequacy of K-SADS versus CBCL

PRIMARY OBJECTIVE

[corrected] To evaluate the convergence between the Kiddie Schedule for Affective Disorders and Schizophrenia (K-SADS) for the diagnosis of psychiatric disorders and the Child Behavior Checklist (CBCL).

RESEARCH DESIGN

Cross-sectional psychiatric study of 72 children with traumatic brain injuries or orthopaedic injuries aged 5-14.

METHODS AND PROCEDURES

Sensitivity, specificity, total predictive value and odds ratio were calculated to evaluate the association between CBCL summary scores and K-SADS diagnosis of at least one psychiatric disorder (K-SADS-1), and of CBCL subscales and K-SADS diagnosis of Attention-Deficit/Hyperactivity Disorder (ADHD). Lowered cut-off scores of t > or = 60 were used.

MAIN OUTCOMES AND RESULTS

Convergence between the CBCL total problem scale and K-SADS-1 was poor. Convergence between 'at least one elevated CBCL subscale' and K-SADS-1, and between CBCL attention problems and social problems scales and K-SADS diagnosis of ADHD was excellent.

CONCLUSIONS

Caution is needed when using the total problem scale of CBCL in predicting global psychological impairment because underestimation of problems is likely. The attention and social problems scales of CBCL can be used to estimate ADHD.

Amantadine treatment following traumatic brain injury in children

PRIMARY OBJECTIVE

The focus of this paper is to review the current literature on the use of amantadine in children who have sustained a head injury.

MAIN OUTCOMES AND RESULTS

A MEDLINE search was conducted and yielded five papers. They were composed of prospective, retrospective and case study designs. Dosage use and side effect profiles were consistent with expected norms. Efficacy was measures primarily by alertness and arousal and positive results were found for all studies on these dimensions. Behavioural and cognitive measures of outcome yielded mixed results.

CONCLUSIONS

The studies reviewed for this paper suggest that amantadine is clinically beneficial for children who have sustained head injuries. Double blind placebo controlled trials with larger sample sizes are needed to further substantiate these findings.

Persistent cognitive dysfunction after traumatic brain injury: A dopamine hypothesis

Traumatic brain injury (TBI) represents a significant cause of death and disability in industrialized countries. Of particular importance to patients the chronic effect that TBI has on cognitive function. Therapeutic strategies have been difficult to evaluate because of the complexity of injuries and variety of patient presentations within a TBI population. However, pharmacotherapies targeting dopamine (DA) have consistently shown benefits in attention, behavioral outcome, executive function, and memory. Still it remains unclear what aspect of TBI pathology is targeted by DA therapies and what time-course of treatment is most beneficial for patient outcomes. Fortunately, ongoing research in animal models has begun to elucidate the pathophysiology of DA alterations after TBI. The purpose of this review is to discuss clinical and experimental research examining DAergic therapies after TBI, which will in turn elucidate the importance of DA for cognitive function/dysfunction after TBI as well as highlight the areas that require further study.

Pharmacological treatment of neurobehavioural sequelae of traumatic brain injury

Neurobehavioural sequelae of traumatic brain injuries require an appropriate/effective pharmacological response in that they represent an important cause of disability. In this field, there is no evidence that reaches the level of a standard: there are guidelines on the use of methylphenidate, donepezil and bromocriptine for the treatment of cognitive disturbances, for the non-use of phenytoin and for the use of beta-blockers for controlling aggressiveness. Resolving a single symptom is not relevant in a rehabilitation project if it is not in the context of a more complex picture of neurobehavioural recovery, in which the positive and negative effects of every therapeutic choice are considered. For example, phenytoin could be used for the positive control of epileptic crises but is not advised since it impedes the recovery of cognitive functions in general. Analogous effects not yet identified may concern benzodiazepine, neuroleptics and other sedatives usually prescribed in cases of cranial trauma. Psychotropic drugs are considered to be able to influence the neuronal plasticity processes. Studies on animals have shown that the administration of D-amphetamine combined with sensorial-motor exercise produces the steady acceleration of motor recovery, which acts as a catalyst to the neurological recovery process. On the other hand, alpha1-NA receptor antagonist drugs produce negative effects; these include clonidine (antihypertension) and haloperidol (neuroleptic). Studies need to be carried out to evaluate the effectiveness of particular drugs. These studies need to focus not only on the disappearance of symptoms but also on the positive and negative effects on overall rehabilitation and on the neurobiological recovery of the patient.

Symptoms of attention-deficit/hyperactivity disorder following traumatic brain injury in children

METHODS

We investigated changes in inattentive and hyperactive symptoms over 2 years following traumatic brain injury (TBI) in relation to preinjury attention-deficit/hyperactivity disorder (ADHD), injury, and socioeconomic status (SES) variables. Postinjury stimulant medication treatment was also documented. Of 175 consecutive patients of ages 5 to 15 years with acute TBI, 148 consented, including 114 without preinjury ADHD (mean age, 10.0 years, SD = 2.76) and 34 with preinjury ADHD (mean age 10.36 years, SD = 2.75). The Schedule for Affective Disorders and Schizophrenia for School-Age Children, Present and Lifetime Version, was administered at baseline and at 6, 12, and 24 months post-injury to assess the presence of nine core inattentive and nine hyperactive symptoms and associated impairment. The baseline assessment was performed within 1 month post-injury to establish preinjury diagnosis.

RESULTS

Nonlinear change in inattentive symptoms in patients without preinjury ADHD contrasted with higher and more stable symptom levels in children with preinjury diagnosis, including the cubic trend (chi2(1) = 6.23, p = .0126). There was also a significant interaction of group x gender effect (chi2(1) = 4.08, p = .0435) as males had higher numbers of inattentive symptoms than females in the preinjury ADHD group. Change in hyperactive symptoms over time also differed by group, including both linear (chi2(1) = 5.42, p = .0199) and cubic trends (chi2(1) = 8.91, p = .0029), reflecting greater and more frequent fluctuations in children without preinjury ADHD. Socioeconomic level also contributed to change in hyperactive symptoms as reflected by the interaction of SES and linear time (chi2(1) = 6.91, p = .009), as well as quadratic time (chi2(1) = 4.90, p = .027). Occurrence of ADHD diagnosed post-injury ranged from 14.5% (12 months) to 18.3% (24 months) in the group without preinjury ADHD compared with a range from 86.4% (12 months) to 96.2% (6 months) in children with preinjury ADHD. In children without preinjury ADHD, SES was the only patient variable that predicted onset of ADHD, t(110) = -2.85, p = .0052. Treatment with stimulant medication post-injury was more frequently associated with preinjury ADHD (39% vs 7% of children without preinjury ADHD), p< .0001 (Fisher exact test). Children with preinjury ADHD who were treated pre-injury with stimulant medication had fewer total symptoms at 24 months post-injury relative to untreated patients with preinjury ADHD (F[1,14] = 3.93, p = 0.069, Cohen's d = 1.28).

CONCLUSION

Change in ADHD symptoms after TBI varies with preinjury diagnosis, reflects injury severity in children without preinjury ADHD, and is treated with stimulant medication mainly in those patients with preinjury ADHD.

Mechanisms of working memory dysfunction after mild and moderate TBI: evidence from functional MRI and neurogenetics

Cognitive complaints are a frequent source of distress and disability after mild and moderate traumatic brain injury (TBI). While there are deficits in several cognitive domains, many aspects of these complaints and deficits suggest that problems in working memory (WM) play an important role. Functional imaging studies in healthy individuals have outlined the neural substrate of WM and have shown that regions important in WM circuitry overlap with regions commonly vulnerable to damage in TBI. Use of functional MRI (fMRI) in individuals with mild and moderate TBI suggests that they can have problems in the activation and allocation of WM, and several lines of evidence suggest that subtle alterations in central catecholaminergic sensitivity may underlie these problems. We review the evidence from fMRI and neurogenetic studies that support the role of catecholaminergic dysregulation in the etiology of WM complaints and deficits after mild and moderate TBI.

Traumatic brain injury in the elderly: diagnostic and treatment challenges

The purpose of this review is to introduce geriatric practitioners to issues and challenges presented in the elderly after onset of traumatic brain injury (TBI). Issues discussed include the magnitude of TBI in the elderly, mechanisms of onset, issues specific to both acute and rehabilitation care for the elderly with TBI, and specific physical and behavioral manifestations of TBI that may need to be addressed on an inpatient or outpatient basis. General guidelines are provided for the diagnosis and treatment of older individuals who have TBI, with specific clinical scenarios illustrating key points.

An Exploration of Central Nervous System Medication Use and Outcomes in Stroke Rehabilitation

Conroy B, Zorowitz R, Horn SD, Ryser DK, Teraoka J, Smout RJ. An exploration of central nervous system medication use and outcomes in stroke rehabilitation.

OBJECTIVE

To study associations between neurobehavioral impairments, use of neurotropic medications, and outcomes for inpatient stroke rehabilitation, controlling for a variety of confounding variables.

DESIGN

Observational cohort study of post-stroke rehabilitation.

SETTING

Six inpatient rehabilitation hospitals in the United States.

PARTICIPANTS

Patients with moderate or severe strokes (N=919).

INTERVENTIONS

Not applicable.

MAIN OUTCOME MEASURES

Discharge disposition, FIM score change, and rehabilitation length of stay (LOS).

RESULTS

Neurobehavioral impairments and use of many medications, including first-generation selective serotonin reuptake inhibitors, older traditional antipsychotic medications, and anti-Parkinsonian neuro-stimulants, have a statistical association with poorer outcomes, whereas use of the atypical antipsychotic medications has a positive association with improvement in motor FIM scores. Counter-intuitively, use of opioid analgesics is associated with a larger motor FIM score change but not an increase in LOS or reduced percentage of discharge to community. There was significant variation in use of neurotropic medications among the 6 study sites during inpatient stroke rehabilitation.

CONCLUSIONS

There are many opportunities to enhance a stroke survivor's ability to benefit from acute inpatient stroke rehabilitation through improved understanding of associations of neurotropic medications with outcomes for different patient groups.

Disorders of Diminished Motivation

Disorders of diminished motivation occur frequently in individuals with traumatic brain injury. Motivation is an ever-present, essential determinant of behavior and adaptation. The major syndromes of diminished motivation are apathy, abulia, and akinetic mutism. Depending on their etiology, disorders of diminished motivation may be a primary clinical disturbance, a symptom of another disorder, or a coexisting second disorder. This article presents a biopsychosocial approach to the assessment and management of motivational impairments in patients with traumatic brain injury. The recognition and differential diagnosis of disorders of diminished motivation, as well as the mechanism and clinical pathogenesis, are discussed.

Magnesium Attenuates Post-Traumatic Depression/Anxiety Following Diffuse Traumatic Brain Injury in Rats

OBJECTIVE

Magnesium (Mg) declines after traumatic brain injury (TBI), a decline believed associated with ensuing neuronal cell death and subsequent functional impairment. While Mg's effects on motor and cognitive deficits following TBI have been well studied, few studies have addressed post-traumatic depression as an outcome parameter, despite its being a major clinical problem with an incidence of between 6 and 77%. We investigated the incidence of post-traumatic depression/anxiety in an animal model of diffuse TBI, and explored the use of magnesium sulfate (MgSO(4)) as an interventional treatment.

METHODS

Diffuse TBI was induced in 32 anesthetized, adult, male Sprague-Dawley rats, using the 2 m impact-acceleration model of injury. At 30 min after injury, half of the rats received 250 micromol/kg i.v. MgSO(4); the other half served as non-treated controls. Before and for 6 weeks after injury, the open-field, spontaneous activity test was used to determine post-traumatic depression/anxiety relative to pre-injury. In this test, animals are placed in a 1-meter square box with 100 squares marked on the base. The number of squares entered in a 5-min period is recorded. Incidence of post-traumatic depression/anxiety was defined as the number of animals demonstrating a reduction in spontaneous activity to less than 100 squares in 5 min. Prior to injury, rats typically entered a mean of 201 +/- 12 (SEM) squares over a 5 min observation period.

RESULTS

At 1 week after injury, non-treated animals had a mean core of 62 +/- 13. The incidence of post-traumatic depression/anxiety in these animals was 61%, which is similar to that observed clinically. In contrast, animals treated with MgSO(4) had a mean activity score of 144 +/- 23 at 1 week after TBI and an incidence of depression/anxiety of less than 30%. The significant difference between groups persisted for the entire 6-week observation period.

CONCLUSIONS

The improvement in post-traumatic depression/anxiety conferred by Mg adds further weight to available evidence of Mg's benefit as a neuroprotective agent after TBI.

Working memory deficits after traumatic brain injury: catecholaminergic mechanisms and prospects for treatment -- a review

PRIMARY OBJECTIVE

To review the neural circuitry and neurochemistry of working memory and outline the evidence for working memory deficits after traumatic brain injury, and the evidence for the use of catecholaminergic agents in the amelioration of these deficits. Current knowledge gaps and research needs are identified.

MAIN OUTCOMES AND RESULTS

Impairments in working memory are a core component of the cognitive deficits associated with traumatic brain injury. Recent progress in understanding the neural circuitry and neurochemistry of working memory suggests that catecholamines play a central role in the activation and regulation of working memory and thus lays a framework in which to consider the use of catecholaminergic agents (dopaminergic and alpha-2 adrenergic agonists) in the treatment of specific cognitive deficits after traumatic brain injury.

CONCLUSIONS

The combined methods of cognitive neuroscience, functional brain imaging and neuropharmacology are proposed as an excellent method for studying working memory deficits. A strong rationale exists for the targeted use of catecholaminergic agonists in the treatment of working memory deficits after traumatic brain injury.

Mood disorders following traumatic brain injury

Mood disorders are a frequent complication of traumatic brain injury that exerts a deleterious effect on the recovery process and psychosocial outcome of brain injured patients. Prior psychiatric history and impaired social support have been consistently reported as risk factors for developing mood disorders after traumatic brain injury (TBI). In addition, biological factors such as the involvement of the prefrontal cortex and probably other limbic and paralimbic structures may play a significant role in the complex pathophysiology of these disorders. Preliminary studies have suggested that selective serotonin reuptake inhibitors such as sertraline, mood stabilizers such as sodium valproate, as well as stimulants and ECT may be useful in treating these disorders. Mood disorders occurring after TBI are clearly an area of neuropsychiatry in which further research in etiology as well as treatment is needed.

Cognitive and behavioural efficacy of amantadine in acute traumatic brain injury: an initial double-blind placebo-controlled study

The objective of the current study was to determine the efficacy of amantadine in improving cognitive and behavioural performance in a traumatic brain injury (TBI) rehabilitation sample. The design was a prospective, randomized, double-blind, placebo-controlled, crossover design. Subjects were 10 adult traumatic brain injury patients in an acute brain injury rehabilitation unit. Subjects received a 2-week trail of amantadine or placebo, followed by a 2-week washout, then a 2-week trail of the alternative (placebo or amantadine). Neuropsychological outcome measures included orientation, attention, executive function, memory, orientation, behaviour, and a composite variable. Results of repeated measures ANOVA and regression analysis of slope/change showed a main effect of time, but no significant difference for amantadine versus placebo. In conclusion, although patients generally improved, this initial exploratory study found no differences in rate of cognitive improvement between subjects given amantadine versus those given placebo. However, the small sample size, heterogeneous population, acute time course, and large number of dependent variables limit power and generalizability. Implications are discussed for further research to better answer questions regarding efficacy of amantadine post-TBI.

Carbamazepine in agitation and aggressive behaviour following severe closed-head injury: results of an open trial

Ten patients presenting agitation and anger outbursts at various stages following a severe closed head injury, were treated in a prospective open trial with carbamazepine, with doses ranging from 400 to 800 mg per day, during 8 weeks. Group analysis demonstrated a statistically significant improvement of a score made up from six target items from the neurobehavioural rating scale. Improvement mainly concerned irritability and disinhibition. A statistically significant improvement was also found with the Agitated Behaviour Scale. Social functioning, as assessed by family or staff ratings of the Katz Adjustment Scale, also significantly improved. No modification of global cognitive functioning was found with the Mini Mental Status Examination. Individual analysis demonstrated that the beneficial effect was important in five cases, moderate in three patients and negligible in two cases. It is concluded that carbamazepine might help to reduce agitated behaviour in brain-injured patients. However, response to treatment demonstrated an important inter-individual variability.

Attention and memory dysfunction after traumatic brain injury: cholinergic mechanisms, sensory gating, and a hypothesis for further investigation

Traumatic brain injury (TBI) is a common occurrence, with a rate of nearly 400,000 new injuries per year. Cognitive and emotional disturbances may become persistent and disabling for many injured persons, and frequently involve symptomatic impairment in attention and memory. Impairments in attention and memory have been well characterized in TBI, and are likely related to disruption of cholinergic functioning in the hippocampus. Additionally, disturbances in this neurotransmitter system may also account for disturbances in sensory gating and discriminative attention in this population. The electroencephalographic P50 waveform of the evoked response to paired auditory stimuli may provide a physiologic market of impaired sensory gating among TBI survivors. The first application of this recording assessment to the TBI population is reported. Preliminary findings in three cases are presented, and the interpretation of impaired sensory gating in this population is discussed. Given the impact of TBI on cholinergic systems, the effects of cholinergic augmentation on attention and memory impairment, and the availability of an electrophysiologic marker of cholinergic dysfunction responsive to cholinergic agents, a testable cholinergic hypothesis for investigation and treatment of these patients is proposed.

Treatment of the psychiatric manifestations of Huntington's disease: a review of the literature

OBJECTIVE

To review the clinical management of the psychiatric aspects of Huntington's disease (HD), namely the mood disorders, psychotic disorders, anxiety symptoms, sleep disorders, disorders of sexuality, and the behavioural changes of apathy, irritability, and aggression. Emphasis is on pharmacologic and psychotherapeutic intervention strategies. In addition, the role of psychiatric intervention in presymptomatic testing is explored.

METHOD

English language literature on the pharmacologic and psychotherapeutic management of the psychiatric manifestations of HD between 1976 and 1996 was critically reviewed.

RESULTS

Few sound studies address the clinical management of the psychiatric aspects of HD; thus, only the broadest conclusions can be drawn. Pharmacologic strategies for the treatment of psychiatric aspects of HD were organized according to the therapeutic agent and class, and psychotherapeutic strategies were discussed.

CONCLUSION

The clinical management of the psychiatric manifestations of HD requires much more complete and systematic study before any definite conclusions as to efficacy of various approaches can be drawn.

Effects of methylphenidate on attentional function after traumatic brain injury. A randomized, placebo-controlled trial

Attention deficits after traumatic brain injury (TBI) are common and disabling. Many pharmacologic agents have been used to ameliorate attention deficits, and considerable interest has focused on methylphenidate (MP) because of its documented efficacy in attention deficit disorder. However, clinical studies of MP in subjects with TBI have yielded mixed results. We examined the effects of MP on attentional function in individuals with TBI referred specifically for attentional assessment and treatment. Subjects were studied in a double-blind, placebo-controlled, repeated crossover design, using five different tasks designed to measure various facets of attentional function. MP produced a significant improvement in the speed of mental processing. Orienting to distractions, most aspects of sustained attention, and measures of motor speed were unaffected. These results suggest that MP may be a useful treatment in TBI but is primarily useful for symptoms that can be attributed to slowed mental processing.

Measurement and treatment of agitation following traumatic brain injury: II. A survey of the Brain Injury Special Interest Group of the American Academy of Physical Medicine and Rehabilitation

OBJECTIVE

Determine national patterns of measuring and treating agitation after traumatic brain injury (TBI) by physiatrists with expressed interest in treating TBI survivors.

DESIGN

A 70% random sample of members of the Brain Injury Special Interest Group of the American Academy of Physical Medicine and Rehabilitation was surveyed by telephone.

MAIN OUTCOME MEASURE

The survey instrument was designed to determine the most common pharmacologic interventions for agitation and, where possible, match each drug with the target behavioral and cognitive characteristics for which it is prescribed. Data were also collected on the manner in which participants measured agitation and judged treatment efficacy.

RESULTS

One hundred twenty-nine of 157 responded, yielding an 82% response rate. The majority of respondents were not measuring agitation in a standard fashion. The five most frequently prescribed drugs by the expert stratum were carbamazepine, tricyclic antidepressants (TCAs), trazodone, amantadine, and beta-blockers. In comparison, the nonexperts most often reported prescribing carbamazepine, beta-blockers, haloperidol, TCAs, and benzodiazepines. Desyrel (p = .06) and amantadine (p = .001) were significantly more likely to be chosen by experts than by nonexperts. Experts chose haloperidol significantly less often than nonexperts (p = .01). Prescription of sedating drugs such as haloperidol or benzodiazepines was not found to be associated with the acuity of injury of TBI patients in the respondent's practice, practice setting, or years of practice since completing residency. Choice of haloperidol to treat agitation was not significantly associated with the degree to which explosive anger, verbal aggression, or physical aggression were considered important to the respondent's definition of agitation.

CONCLUSIONS

The majority of physiatrists surveyed did not formally measure agitation. Treatment strategies differ significantly between general physiatrists and those who specialize in the treatment of patients with TBI. The breadth of pharmacologic agents and strategies identified in this survey probably reflects the lack of research specific to the pathophysiology of the disorder of posttraumatic agitation.

Evaluation of brain injury related behavioral disturbances in community mental health centers

As a result of improved emergency trauma services, more individuals suffering a traumatic brain injury are surviving. Unfortunately, most of these survivors suffer chronic neuropsychiatric sequelae related to both the brain damage and the psychosocial impact of the injury on self-esteem, self-image, primary role, and vocational function. Current community supports are often inadequate to deal with the complex array of neurologic and psychiatric difficulties. This article outlines common features of brain injury, explores the link between these features and the common neuropsychiatric sequelae of brain injury, and suggests some principles helpful in the evaluation of the behaviorally challenged brain injured patient.

Patients with traumatic brain injury referred to a rehabilitation and re-employment programme: social and professional outcome for 508 Finnish patients 5 or more years after injury

We studied influence of age and educational level before injury on the social and vocational outcome among a group of traumatic brain injury (TBI) patients with post-injury problems in their education and employment. Patients with TBI, followed up for at least 5 years, and who were admitted to a rehabilitation and re-employment programme, were selected for evaluation of long-term outcome. We used the Glasgow Coma Scale (GCS) scores at the time of emergency admission to the hospital to measure brain injury severity. Age at the time of TBI and educational status before TBI were correlated with the outcome measures at the end of follow-up separately in each category of brain injury severity. The study was carried out at the Kauniala outpatient neurological clinic, which specializes in brain injuries in Finland; it works closely with the Departments of Neurology and Neurosurgery at the Helsinki University Central Hospital. Main outcome measures were functional outcome measured by the Glasgow Outcome Scale (GOS), the educational level reached, and post-injury occupation, as well as the incapacity for work at the end of follow-up. In the severe category of brain injuries, children 7 years or younger at the time of injury suffered severe disability as measured by the GOS scores more often than did the older age groups (p = 0.010, chi 2). They were less often capable of independent employment (p = 0.011, chi 2) than the children injured at the age of 8-16. Patients with a higher education usually had a better outcome. In the category of mild brain injuries the majority of the patients, regardless of age, recovered well according to the GOS, and were capable of independent employment at the end of follow-up. Our patients were selected from the TBI population as survivors with problems in education and re-employment. Those with severe injury sustained early in life (childhood and early teens) coupled with poor educational attainment had relatively worse social and vocational outcome; better outcomes were enjoyed by those severely injured individuals whose injuries were sustained later (late teens or early adulthood). In the groups of patients with moderate and mild brain injuries such a relationship was not found between age or pre-injury education and outcome.

Subacute methylphenidate treatment for moderate to moderately severe traumatic brain injury: a preliminary double-blind placebo-controlled study

OBJECTIVE

To determine the effect of subacute administration of methylphenidate on recovery from moderate to moderately severe closed head injury.

DESIGN

Double-blind placebo-controlled with random assignment. Patients were enrolled when their Galveston Orientation and Amnesia Test score was at least 65. Drug/placebo treatment began the day following baseline cognitive assessment and continued for 30 consecutive days. Follow-up evaluations were conducted at 30 and 90 days after baseline, after discontinuation of drug/placebo.

SETTING

A level I trauma center.

PATIENTS

Twenty-three patients ranging in age from 16 to 64 years. Head injury severity ranged from moderately severe (Glasgow Coma Score [GCS] < or = 8, no intracranial pressure monitor) to "complicated mild" (GCS from 13 to 15 with positive computed tomography brain scan). Thirty-day follow-up was based on 12 patients, whereas 90-day evaluation was based on 9 patients, with complicated mild head injuries excluded from the analyses.

INTERVENTIONS

Methylphenidate administered twice daily at a dose of .30 mg/kg; placebo administered according to the same schedule in identical pill form.

MAIN OUTCOME MEASURES

The Disability Rating Scale (DRS) and tests of attention, memory, and vigilance.

RESULTS

The methylphenidate group was significantly better at 30 days on the DRS (p < .02), and on tests of attention (p < .03) and motor performance (p, .05). No significant differences were noted between groups at 90 days.

CONCLUSIONS

Subacute administration of methylphenidate after moderately severe head injury appeared to enhance the rate but not the ultimate level of recovery as measured by the DRS and tests of vigilance. Problems with possible selection bias and small sample size limit generalization of results.

Postacute brain injury rehabilitation

This review compares outcomes of adult postacute brain injury rehabilitation (PABIR) with natural recovery after brain injury. Potential outcome predictors and the effectiveness of behavioral, cognitive, pharmacologic, and vocational interventions are also appraised. The importance of standardized outcome assessment is discussed in the context of other research considerations. Although generally uncontrolled, the studies reviewed document benefits for many individuals with brain injury, including increased independence and a rate of return to independent work or training that exceeds 50% and may reach 60% to 80% for intensive comprehensive (holistic) day treatment programs. Available research is sufficiently encouraging to recommend more carefully controlled randomized studies. Future research should emphasize the development of standardized measures of patient characteristics and outcomes, and matching of patient characteristics with optimal rehabilitation approaches.

Use of Sinemet in locked-in syndrome: a report of two cases

Locked-in syndrome describes a neurological condition usually associated with infarction of the ventral pons. Such patients are diagnosed with quadriplegia, lower cranial nerve paralysis, and mutism. The patient is alert but communication is severely limited and usually is accomplished by blinking or using vertical eye movements. The rehabilitative management of locked-in syndrome has consisted of preventative and supportive measures. In this study we report two cases of locked-in syndrome which were treated successfully with Sinemet (DuPont Pharmaceuticals, Wilmington, DE). Even though the exact neuropharmacological mechanism is unclear, the dramatic improvement in these cases, as well as in one other published case report, dictates that use of Sinemet should be considered in the management of locked-in syndrome.

The dexamethasone suppression test and the diagnosis of depression in adults with severe and profound developmental disabilities

The dexamethasone suppression test (DST) was administered to 40 adults with severe and profound mental retardation. All participants were free from known conditions which may have given misleading results from cortisol assay. Of nine participants who showed symptoms possibly indicating depression the DST results concurred in two cases (i.e. there were two true-positives). However there were four or five (depending on criteria adopted) false-positive DST results. There did not appear to be a consistent behavioural profile for positive DST responders. With sensitivity to possible depression estimated at 22%, and a diagnostic confidence of < 35%, these data do not support recommendations that the DST is useful for assisting in diagnosis of depression in this population.

Neuropsychiatric sequelae of stroke and traumatic brain injury: the role of psychostimulants

OBJECTIVE

The primary purpose of this article is to review certain neuropsychiatric sequelae of stroke and traumatic brain injury (TBI), and the role of the psychostimulants methylphenidate (MPD) and dextroamphetamine (DAMP) in their treatment.

METHOD

A general review of the topic is presented. Controlled and uncontrolled studies involving the use of the psychostimulants are discussed. These consist of 11 studies listed with Medline 2000 that deal specifically with stroke or head injury, with the oldest study reviewed dating back to 1984. Studies concerning the use of psychostimulants in the medically or neurologically ill are reviewed to the extent that they are pertinent.

RESULTS

The current literature consists primarily of uncontrolled case studies. However, these are reviewed and found to suggest a role for the use of the psychostimulants, which is discussed.

CONCLUSIONS

In general, these drugs appear to be a reasonable treatment choice for certain types of mood, behavior, and cognitive symptoms following brain injury. However, it is noted that larger scale controlled studies are needed to adequately assess the clinical usefulness of these drugs.

Brain injury: personality, psychopathology and neuropsychology

This study investigated the relationship between brain injury and personality, using the Luria-Nebraska Neuropsychological Battery and the Clinical Analysis Questionnaire as measurement tools. Psychopathological factors, as opposed to normal personality traits, were highly correlated with measures of brain injury. Depression, in particular, was found to be substantially involved in the sequelae of brain injury for this sample. A trend in the data revealed that suicidal depression and anxious depression were differentially related to deficits on two scales of the LNNB. Patients with evidence of suicidal depression were also more sensitive to emotional dysfunction in other areas. Few differences were found between patients with traumatic brain injury and those with other types of brain injuries. Results suggest that measures of psychopathology can provide important supplementary information to neuropsychological assessment, above that obtained from measures of brain functioning alone. Controlled studies should investigate the relationship between psychopathology and neuropsychology more thoroughly to provide clearer determinations of its involvement in the rehabilitation of the brain-injured person.

ECT in the treatment of patients with neurological and somatic disease

OBJECTIVE

An evaluation of the safety and efficacy of electroconvulsive therapy (ECT), for the treatment of patients with severe medical and neurological illness, was undertaken.

METHOD

The English-language literature reporting the use of ECT in patients with neurological and somatic disease was reviewed. This review included reports describing ECT used for the treatment of affective disturbances and catatonia in patients with concurrent neurological or somatic disease, as well as reports dealing with the efficacy of ECT for the treatment of certain neurological conditions for which it has been reported to have some benefit independent of its psychiatric effect.

CONCLUSIONS

ECT is safe and effective for the treatment of affective and catatonic disorders in patients with most neurological and medical diseases, including elderly and debilitated patients with multiple illnesses, if the specific medical risks are carefully evaluated in each case, and appropriate modifications of technique are used to reduce the risk of potential complications. Apart from its use in psychiatry, ECT has been reported to have therapeutic effects in Parkinson's disease, neuroleptic malignant syndrome, aggressive behavioral disorders following brain injury, certain forms of epilepsy, and some forms of delirium due to toxic or metabolic encephalopathies. The potential for ECT to play an active role in the clinical management of patients with these disorders, many of whom are presently refractory to maximal medical treatment, should be evaluated by systematic studies.

Ethics in brain injury rehabilitation: existential choices among western cultural beliefs

The following issues in the practice of brain injury rehabilitation are explored: (1) validity of support for efficacy based on experience in clinical practice, (2) validity of support for efficacy based on research, (3) consumer protection, (4) qualifications and regulation of individual providers, (5) regulation of programme development and marketing. Ethical responses to these issues from each of three cultural belief systems (humanism, science and self-interest) are examined from a metaphilosophical perspective based on contemporary cognitive psychology and on philosophies of social constructionism and existentialism.

Ultra-rapid cycling bipolar affective disorder following a closed-head injury

A young adult with no prior history of affective disease suffered the onset of a rapid cycling bipolar illness, marginally responsive to psychotropic medications, following a mild closed-head injury, and persisting after the cognitive effects of the injury had resolved. A concurrence of findings on the neurological examination, neurobehavioural examination, SPECT scan, EEG and neuropsychological test battery suggested the presence of a diffuse cerebral injury with a predominance of left frontotemporal findings. This case demonstrates that a severe and disabling mood disorder may follow a mild head injury, and that its course may be independent of cognitive impairment and recovery.

Chlorpromazine-induced psychosis after brain injury

Antipsychotic agents, most often used for treatment of schizophrenia, are sometimes prescribed for the agitated patient with an organic brain disorder. We report the case of a brain-injured patient who was prescribed chlorpromazine for agitation and who developed a delusional state while taking this antipsychotic agent. The emergence of this delusional state coincided with the exacerbation of certain cognitive deficits. Possible mechanisms for this phenomenon are discussed. Caution is advised when prescribing neuroleptics for patients with traumatic brain injury, especially those agents with significant cognitive side-effects or with a significant potential to precipitate seizures.

Topographic mapping of long latency "cognitive" event-related potentials (P 300): a double-blind, placebo-controlled study with amantadine in mild dementia

Amantadine is generally used in the prophylaxis of infection with influenza A, in the treatment of Parkinson's disease and in the treatment of neuroleptic side effects. In this study acute effects of amantadine infusions on event-related potentials (ERP) were studied in 20 mildly demented patients diagnosed according to DSM-III-R criteria. Each patient was treated, in randomized order, with 0.2 g amantadine-sulfate in 500 ml NaCl and 500 ml NaCl placebo, i.v. over one hour with an interval of two weeks in-between. ERPs were investigated in an auditory odd-ball paradigm before as well as 5 hours after the infusion. In addition to 17 EEG records, vertical and horizontal EOGs were recorded. After EOG-minimization and visual artifact rejection the peak latencies of the spatial average were determined by an automatic procedure. There was no effect of amantadine on ERP latencies. N1 of the non-target showed a trend towards amplitude augmentation, P2 amplitude was reduced. As compared to placebo, P300 amplitude of targets was significantly augmented by 3.1 microV (30% of pre-treatment value), confirming the hypothesis that amantadine may influence the P 300 amplitude in the sense of an improved availability of cognitive processing resources.

Mixed neurologic and psychiatric disorders: pharmacological issues

The number of patients with mixed neurologic and psychiatric disturbances is large. The psychiatric disturbances are often atypical in presentation and fit poorly into standard psychiatric nomenclature. They can be difficult to treat using standard psychopharmacologic approaches. This report reviews the impact of brain dysfunction on the use of conventional and nonconventional psychotropic agents in this mixed population.