Mild traumatic brain injury

Predictors of Postconcussive Symptoms 3 Months After Mild Traumatic Brain Injury

Authors: Ponsford J, Cameron P, Fitzgerald M, Grant M, Mikocka-Walus A, Schönberger M.

Objective: There is continuing controversy regarding predictors of poor outcome following mild traumatic brain injury (mTBI). This study aimed to prospectively examine the influence of preinjury factors, injury-related factors, and postinjury factors on outcome following mTBI. Method: Participants were 123 patients with mTBI and 100 trauma patient controls recruited and assessed in the emergency department and followed up 1 week and 3 months postinjury. Outcome was measured in terms of reported postconcussional symptoms. Measures included the ImPACT Post-Concussional Symptom Scale and cognitive concussion battery, including Attention, Verbal and Visual memory, Processing Speed and Reaction Time modules, pre- and postinjury SF-36 and MINI Psychiatric status ratings, VAS Pain Inventory, Hospital Anxiety and Depression Scale, PTSD Checklist-Specific, and Revised Social Readjustment Scale. Results: Presence of mTBI predicted postconcussional symptoms 1 week postinjury, along with being female and premorbid psychiatric history, with elevated HADS anxiety a concurrent indicator. However, at 3 months, preinjury physical or psychiatric problems but not mTBI most strongly predicted continuing symptoms, with concurrent indicators including HADS anxiety, PTSD symptoms, other life stressors and pain. HADS anxiety and age predicted 3-month PCS in the mTBI group, whereas PTSD symptoms and other life stressors were most significant for the controls. Cognitive measures were not predictive of PCS at 1 week or 3 months. Conclusions: Given the evident influence of both premorbid and concurrent psychiatric problems, especially anxiety, on postinjury symptoms, managing the anxiety response in vulnerable individuals with mTBI may be important to minimize ongoing sequelae. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

Concussions: What a neurosurgeon should know about current scientific evidence and management strategies

Authors: Neal MT, Wilson JL, Hsu W, Powers AK.

BACKGROUND: There has been a tremendous amount of interest focused on the topic of concussions over the past few decades. Neurosurgeons are frequently consulted to manage patients with mild traumatic brain injuries (mTBI) that have radiographic evidence of cerebral injury. These injuries share significant overlap with concussions, injuries that typically do not reveal radiographic evidence of structural injury, in the realms of epidemiology, pathophysiology, outcomes, and management. Further, neurosurgeons often manage patients with extracranial injuries that have concomitant concussions. In these cases, neurosurgeons are often the only "concussion experts" that patients encounter.
RESULTS: The literature has been reviewed and data have been synthesized on the topic including sections on historical background, epidemiology, pathophysiology, diagnostic advances, clinical sequelae, and treatment suggestions, with neurosurgeons as the intended target audience.
CONCLUSIONS: Neurosurgeons should have a fundamental knowledge of the scientific evidence that has developed regarding concussions and be prepared to guide patients with treatment plans.

A case-control study examining whether neurological deficits and PTSD in combat veterans are related to episodes of mild TBI

Authors: Ruff RL, Riechers RG 2nd, Wang XF, Piero T, Ruff SS.

BACKGROUND: Mild traumatic brain injury (mTBI) is a common injury among military personnel serving in Iraq or Afghanistan. The impact of repeated episodes of combat mTBI is unknown.
OBJECTIVE: To evaluate relationships among mTBI, post-traumatic stress disorder (PTSD) and neurological deficits (NDs) in US veterans who served in Iraq or Afghanistan.
METHODS: This was a case-control study. From 2091 veterans screened for traumatic brain injury, the authors studied 126 who sustained mTBI with one or more episodes of loss of consciousness (LOC) in combat. Comparison groups: 21 combat veterans who had definite or possible episodes of mTBI without LOC and 21 veterans who sustained mTBI with LOC as civilians.
RESULTS: Among combat veterans with mTBI, 52% had NDs, 66% had PTSD and 50% had PTSD and an ND. Impaired olfaction was the most common ND, found in 65 veterans. The prevalence of an ND or PTSD correlated with the number of mTBI exposures with LOC. The prevalence of an ND or PTSD was >90% for more than five episodes of LOC. Severity of PTSD and impairment of olfaction increased with number of LOC episodes. The prevalence of an ND for the 34 combat veterans with one episode of LOC (4/34=11.8%) was similar to that of the 21 veterans of similar age and educational background who sustained civilian mTBI with one episode of LOC (2/21=9.5%, p-NS).
CONCLUSIONS: Impaired olfaction was the most frequently recognised ND. Repeated episodes of combat mTBI were associated with increased likelihood of PTSD and an ND. Combat setting may not increase the likelihood of an ND. Two possible connections between mTBI and PTSD are (1) that circumstances leading to combat mTBI likely involve severe psychological trauma and (2) that altered cerebral functioning following mTBI may increase the likelihood that a traumatic event results in PTSD.

Brain Aging and Regeneration after Injuries: an Organismal approach

Authors: Buga AM, Vintilescu R, Pop OT, Popa-Wagner A.

Aging is associated with a decline of locomotor, sensory and cognitive performance in humans and experimental animals. The rate and pattern of organismal senescence may be regulated in part by changes in multiple genes involved in multiple processes. While this theory is supported by genetic data in lower organisms, a lack of direct experimental evidence in higher organisms has contributed to a broader acceptance of the "stochastic aging" model, in which accumulating, random damaging biological events play an important role. However, these insults alone cannot account for the inexorable deterioration and loss of function that characterizes aging. The higher the complexity of a system, the less obvious is the effect of genetic regulation on aging and the life span, indicating that epigenetic factors play an important role in aging. Most importantly, we present evidence that aging systems do retain some capacity for regeneration and functional recovery after injuries to the central nervous system like cerebral ischemia.

High prevalence of chronic pituitary and target-organ hormone abnormalities after blast-related mild traumatic brain injury

Authors: Wilkinson CW, Pagulayan KF, Petrie EC, Mayer CL, Colasurdo EA, Shofer JB, Hart KL, Hoff D, Tarabochia MA, Peskind ER.

Studies of traumatic brain injury from all causes have found evidence of chronic hypopituitarism, defined by deficient production of one or more pituitary hormones at least 1 year after injury, in 25-50% of cases. Most studies found the occurrence of posttraumatic hypopituitarism (PTHP) to be unrelated to injury severity. Growth hormone deficiency (GHD) and hypogonadism were reported most frequently. Hypopituitarism, and in particular adult GHD, is associated with symptoms that resemble those of PTSD, including fatigue, anxiety, depression, irritability, insomnia, sexual dysfunction, cognitive deficiencies, and decreased quality of life. However, the prevalence of PTHP after blast-related mild TBI (mTBI), an extremely common injury in modern military operations, has not been characterized. We measured concentrations of 12 pituitary and target-organ hormones in two groups of male US Veterans of combat in Iraq or Afghanistan. One group consisted of participants with blast-related mTBI whose last blast exposure was at least 1 year prior to the study. The other consisted of Veterans with similar military deployment histories but without blast exposure. Eleven of 26, or 42% of participants with blast concussions were found to have abnormal hormone levels in one or more pituitary axes, a prevalence similar to that found in other forms of TBI. Five members of the mTBI group were found with markedly low age-adjusted insulin-like growth factor-I (IGF-I) levels indicative of probable GHD, and three had testosterone and gonadotropin concentrations consistent with hypogonadism. If symptoms characteristic of both PTHP and PTSD can be linked to pituitary dysfunction, they may be amenable to treatment with hormone replacement. Routine screening for chronic hypopituitarism after blast concussion shows promise for appropriately directing diagnostic and therapeutic decisions that otherwise may remain unconsidered and for markedly facilitating recovery and rehabilitation.

Trends in the Incidence of Physician-Diagnosed Mild Traumatic Brain Injury Among Active Duty US Military Personnel between 1997 and 2007

Authors: Cameron KL, Marshall SW, Sturdivant RX, Lincoln AE.

Mild traumatic brain injury (mTBI) has been described as the most common form of traumatic brain injury within military populations; however, few epidemiologic studies have examined incidence rates for mTBI in this population. The objective of this study was to examine trends in the incidence of mTBI among active duty US service members between 1997 and 2007. Specifically, we were interested in evaluating trends in the incidence rates in relation to the initiation of combat operations in Iraq and Afghanistan. A retrospective cohort study was conducted utilizing data extracted from the Defense Medical Surveillance System to identify all incident cases of mTBI within the study population. The primary outcome of interest was the incidence rate of mTBI per 1000 person-years. Multivariable Poisson regression was used to analyze the data. There were 98,012 mTBI cases and 14,956,955 person-years of follow-up, for an overall incidence rate of 6.55 (95%CI: 6.51, 6.59) per 1,000 person-years. There was a steady increase in the mTBI rate over time. The average change in the mTBI rate was 8.5% (95%CI: 8.2%, 8.8%) per year; however, the rate rose dramatically in the last two years of the study period. Overall, for 2006-2007 vs. 1997-2005, the rate ratio was 1.61 (95%CI: 1.58, 1.65). The greatest increase in the rate of mTBI was observed among those serving in Iraq, who experienced a 38.4% (95%CI: 35.4%, 41.1%) annual increase in new cases. The observed increase in the incidence of mTBI in this population has significant policy implications in terms of allocating appropriate healthcare resources.


Subscribe to RSS - Mild traumatic brain injury