Heterogeneity of health-related quality of life after mild traumatic brain injury with systemic injury: a cluster analytic approach.

PURPOSE: Health-related quality of life (HRQoL) is a key component of evaluating outcome after mild traumatic brain injury (mTBI). As outcome is heterogeneous following mTBI, it is relevant to examine individual differences in HRQoL. This study investigated whether multiple homogenous subgroups could be meaningfully identified, 10 weeks after hospitalised mTBI with systemic injury, on the basis of HRQoL profiles. METHODS: Ninety-one adults were assessed for HRQoL, pain, fatigue, sleep quality, psychological distress, cognition and post-concussion symptoms. RESULTS: Cluster analyses revealed three separate subgroups based on physical, mental, social and energy HRQoL. One group (42%) demonstrated normative levels of HRQoL on all subdomains. The remaining two groups demonstrated significantly reduced HRQoL on all subdomains. These groups had equivalently poor mental, social and energy HRQoL, but the smallest group (27%) had significantly poorer physical HRQoL. Multinomial logistic regression revealed that pain significantly and independently predicted group membership for the particularly poor physical HRQoL group. Fatigue was the only significant independent predictor of group membership for the remaining group with reduced HRQoL. CONCLUSION: These findings suggest more than 50% of hospitalised individuals with mTBI and systemic injury, have reduced HRQoL, 10 weeks after mTBI. Pain and fatigue warrant clinical attention in these individuals.IMPLICATIONS FOR REHABILITATIONMild traumatic brain injury is a common event that has been shown to be associated with persistently reduced health-related quality of life in approximately 50% of individuals 6 to 12 months after injury.Health-related quality of life likely varies between individuals after injuryRelative to the "normal" population, most individuals in this cohort of individuals with mTBI and systemic injury had reduced mental, social and energy quality of life 10 weeks after injury.Fatigue and pain are important factors in reduced health-related quality of life after mTBI with systemic injury.Further research is needed to determine whether these fatigue and pain issues are related to mTBI-factors, such as headache, and/or related to systemic injury factors, which are common in the mTBI population.

The relationship between cognition and white matter tract damage after mild traumatic brain injury in a premorbidly healthy, hospitalised adult cohort during the post-acute period.

Introduction: Recent developments in neuroimaging techniques enable increasingly sensitive consideration of the cognitive impact of damage to white matter tract (WMT) microstructural organisation after mild traumatic brain injury (mTBI). Objective: This study investigated the relationship between WMT microstructural properties and cognitive performance. Participants setting and design: Using an observational design, a group of 26 premorbidly healthy adults with mTBI and a group of 20 premorbidly healthy trauma control (TC) participants who were well-matched on age, sex, premorbid functioning and a range of physical, psychological and trauma-related variables, were recruited following hospital admission for traumatic injury. Main measures: All participants underwent comprehensive unblinded neuropsychological examination and structural neuroimaging as outpatients 6-10 weeks after injury. Neuropsychological examination included measures of speed of processing, attention, memory, executive function, affective state, pain, fatigue and self-reported outcome. The WMT microstructural properties were estimated using both diffusion tensor imaging (DTI) and neurite orientation dispersion and density imaging (NODDI) modelling techniques. Tract properties were compared between the corpus callosum, inferior longitudinal fasciculus, uncinate fasciculus, anterior corona radiata and three segmented sections of the superior longitudinal fasciculus. Results: For the TC group, in all investigated tracts, with the exception of the uncinate fasciculus, two DTI metrics (fractional anisotropy and apparent diffusion coefficient) and one NODDI metric (intra-cellular volume fraction) revealed expected predictive linear relationships between extent of WMT microstructural organisation and processing speed, memory and executive function. The mTBI group showed a strikingly different pattern relative to the TC group, with no relationships evident between WMT microstructural organisation and cognition on most tracts. Conclusion: These findings indicate that the predictive relationship that normally exists in adults between WMT microstructural organisation and cognition, is significantly disrupted 6-10 weeks after mTBI and suggests that WMT microstructural organisation and cognitive function have disparate recovery trajectories.

Psychological distress and gender predict cognitive complaint after adult civilian mild traumatic brain injury in pre-morbidly healthy adults.

Subjective cognitive symptoms are common after mild traumatic brain injury (mTBI), and are associated with important outcome factors including return to work. This study examined self-reported cognitive symptoms in mTBI and trauma controls (TCs), and explored psychological distress and gender as predictors of these symptoms. Pre-morbidly healthy adults with mTBI (n = 68) and general trauma (n = 40) were prospectively recruited from inpatient hospital wards and assessed 6-10 weeks post-injury. Primary measures included self-reported cognitive symptoms, post-concussion symptoms, and psychological distress. Groups were matched on all background variables, including objective cognitive performance. Within this context, subjective cognitive symptoms were significantly elevated after mTBI relative to TCs (t = 3.396, p = .001). In contrast, there was no difference in post-concussion symptoms between groups (t = 1.275, p = .206). Psychological distress (ß = .536, p < .001) and gender (ß = .253, p = .012) predicted subjective cognitive symptoms in mTBI, with females and those with higher distress reporting greater symptoms. Unlike general post-concussion symptoms, subjective cognitive symptoms were elevated after mTBI relative to TCs, suggesting that mTBI-specific factors underly this elevation. Females and individuals with high psychological distress are important subgroups to consider for potential intervention following mTBI.

Cerebral microhaemorrhage count is related to processing speed, but not level of symptom reporting, independently of age, psychological status and premorbid functioning, after first-ever mild traumatic brain injury.

Cerebral microhaemorrhage is a commonly identified neuropathological consequence of mild traumatic brain injury (mTBI) and can be identified in vivo using susceptibility weighted imaging (SWI). This study aimed to determine whether SWI-detected microhaemorrhages are more common in individuals after a single, first-ever, mTBI event relative to trauma controls (TC) and to investigate whether a linear relationship exists between microhaemorrhage numbers and cognition or symptom reporting in the post-acute period after injury, independently of age, psychological status and premorbid level of functioning. Microhaemorrhagic lesions were identified by expert clinical examination of SWI for 78 premorbidly healthy adult participants who were admitted to hospital after a traumatic injury and had suffered a first-ever mTBI (n = 47) or no head strike (n = 31). Participants underwent objective cognitive examination of processing speed, attention, memory, and executive function as well as self-reported post-concussion symptomatology. Bootstrapping analyses were used as data were not normally distributed. Analyses revealed that the mTBI group had significantly more microhaemorrhages than the TC group (Cohen's d = 0.559). These lesions were only evident in 28% of individuals. The mTBI participants demonstrated a significant linear association between number of microhaemorrhages and processing speed, independently of age, psychological status, or premorbid level of functioning. This study shows that a single mTBI causes cerebral microhaemorrhages to occur in a minority of premorbidly healthy individuals. Greater microhaemorrhage count is independently associated with slower processing speed, but not symptom reporting, during the post-acute injury period.

The relationship between cognitive reserve and outcome after controlling for psychological status and sex following mild traumatic brain injury.

OBJECTIVE: Cognitive reserve is the brain's ability to optimize performance by differentially recruiting brain networks. It is easily measured and is reportedly associated with post-concussion symptom (PCS) reporting in the post-acute period after mild traumatic brain injury (mTBI). Past studies have not examined whether this relationship exists when the influence of psychological status is removed, despite this factor being strongly associated with symptom reporting. This study investigated whether cognitive reserve predicts PCS reporting or cognitive complaint in the post-acute period after mTBI, independently from psychological status and sex. METHOD: Ninety-four pre-morbidly healthy adults were assessed on three measures of cognitive reserve, as well as measures of post-concussion symptoms, cognitive complaint, and psychological status. RESULTS: Bivariate analyses revealed significant relationships between measures of cognitive reserve and both PCS reporting (p < 0.01) and cognitive complaint (<.05). After removing the influence of psychological distress and sex, however, no measure of cognitive reserve significantly predicted any type of symptom reporting. CONCLUSION: These findings indicate that cognitive reserve does not independently predict symptom reporting 9 weeks after mTBI, and clinicians should not incorporate this factor into their decision-making regarding likelihood of ongoing symptom reporting and the consequent need for intervention in the post-acute period after mTBI.

Sex predicts post-concussion symptom reporting, independently of fatigue and subjective sleep disturbance, in premorbidly healthy adults after mild traumatic brain injury.

The relationship between sex and post-concussion symptom (PCS) reporting after mild traumatic brain injury (mTBI) is not well understood. Subjective sleep disturbance and fatigue impact PCS reporting after mTBI and show sex differences in the normal population. This study investigated whether sex had a relationship with PCS reporting after mTBI, independently of self-reported sleep disturbance and fatigue. Ninety-two premorbidly healthy adults in the post-acute period after mTBI completed the Rivermead Post-Concussion Symptoms Questionnaire, the Pittsburgh Sleep Quality Index, the Multidimensional Fatigue Inventory and measures of depression, anxiety and post-traumatic stress symptomatology. Females (n = 23) demonstrated higher levels of fatigue (p = .019) and greater psychological distress (p = .001) than males (n = 69), but equivalent levels of sleep disturbance (p = .946). Bootstrapping analyses were undertaken because PCS responses were not normally distributed. Female sex predicted greater PCS reporting (p = .001), independently of subjective sleep disturbance, fatigue, psychological distress and litigation status. The current findings support and extend previous work showing premorbidly healthy females are at higher risk of experiencing elevated PCS after mTBI than males in the post-acute period after mTBI. It may be beneficial for clinicians to be particularly sensitive to increased symptom reporting after mTBI in females, irrespective of sleep quality, fatigue or psychological status.

Personality traits beyond Neuroticism predict post-concussive symptomatology in the post-acute period after mild traumatic brain injury in premorbidly healthy adults.

There is growing evidence that an individual's personality traits are related to post-concussion symptomatology beyond the acute period after mild traumatic brain injury (mTBI). Few studies, however, have analyzed this impact beyond the personality trait of Neuroticism. We examined the impact of personality traits on post-concussion symptoms (PCS) by measuring the Big Five personality domains and their lower-order aspects in 87 pre-morbidly healthy participants assessed 6-12 weeks post-mTBI (n = 53) or physical trauma (n = 34). As expected, Neuroticism predicted PCS endorsement in both groups. Conscientiousness and Openness/intellect were predictive of lower PCS endorsement, but only in the mTBI group. Withdrawal, one aspect within the Neuroticism domain, independently predicted PCS endorsement in the mTBI group; the remaining Neuroticism aspect, Volatility, did not predict PCS endorsement in either group. These findings suggest that individuals high in Neuroticism are more likely to report PCS following mTBI and that this relationship is driven by susceptibility to depression/anxiety symptoms (Withdrawal aspect) rather than irritability (Volatility aspect). Further, they suggest that the current focus on the relationship between Neuroticism and PCS reporting in individuals with mTBI should be broadened to include other personality domains, such as Conscientiousness and Openness/intellect.

Frequency and extent of cognitive complaint following adult civilian mild traumatic brain injury: a systematic review and meta-analysis.

OBJECTIVE: Cognitive symptoms are associated with return to work, healthcare use and quality of life after mild traumatic brain injury (mTBI). Additionally, while overall 'post-concussion' symptoms are often present at similar levels in mTBI and control groups, cognitive complaints may be specifically elevated in mTBI. A systematic review and meta-analysis was conducted to investigate the frequency and extent of cognitive complaints following adult civilian mTBI, and compare it to the frequency and extent of complaints in control populations (PROSPERO: CRD42020151284). METHOD: This review included studies published up to March 2022. Thirteen studies were included in the systematic review, and six were included in the meta-analysis. Data extraction and quality assessment were conducted by two independent reviewers. RESULTS: Cognitive complaints are common after mTBI, although reported rates differed greatly across studies. Results suggested that mTBI groups report cognitive complaints to a significantly greater extent than control groups (Hedges' g = 0.85, 95% CI 0.31-1.40, p = .0102). Heterogeneity between studies was high (τ2 = 0.20, 95% CI 0.04-1.58; I2 = 75.0%, 95% CI 43.4%-89.0%). Between-group differences in symptom reporting were most often found when healthy rather than injured controls were employed. CONCLUSIONS: Cognitive complaints are consistently reported after mTBI, and are present at greater levels in mTBI patients than in controls. Despite the importance of these complaints, including in regards to return to work, healthcare use and quality of life, there has been limited research in this area, and heterogeneity in research methodology is common.

Cognitive complaint and objective cognition during the post-acute period after mild traumatic brain injury in pre-morbidly healthy adults.

Primary Objective:The most widely used proxies of cognitive complaint after mTBI are post-concussion syndrome (PCS) symptom checklists, which do not have a clear relationship with cognition. This study investigated whether an mTBI-specific cognitive complaint measure would have clearer associations with objective cognition than a widely used PCS symptom checklist.Research Design:An observational design was used. A sample of 109 participants (52 mTBI and 57 healthy controls) completed a PCS symptom checklist, a cognitive complaint measure, and measures of information processing speed, attention, memory, executive function, depression and anxiety.Main Outcomes and Results:In the healthy control group, cognitive complaint was significantly associated with objective cognitive performance and was not associated with psychological status. In contrast, PCS endorsement was unrelated to objective cognition but was associated with psychological status. For the mTBI group, neither PCS endorsement nor cognitive complaint was associated with cognitive performance, but both measures were associated with psychological status.Conclusions:This study indicates that neither cognitive nor PCS symptom measures are reliable indicators of underlying cognitive function in the post-acute period after mTBI. Further, suffering an mTBI may affect the linear relationship that exists between cognitive symptom endorsement and cognitive function in healthy adults.

Investigating the Effect of Fatigue and Psychological Distress on Information Processing Speed in the Postacute Period After Mild Traumatic Brain Injury in Premorbidly Healthy Adults.

Impairments in processing speed under conditions of increasing cognitive load have been reported in individuals with mild traumatic brain injury (mTBI). In other conditions that are also associated with white matter disruption, both psychological distress and fatigue have been shown to underlie this impairment. OBJECTIVE: the current study aimed to investigate whether slowing of processing abilities under conditions of greater cognitive load is independent of fatigue and psychological status in premorbidly healthy individuals with subacute mTBI. METHOD: using a prospective observational design, we examined 84 individuals with mTBI approximately 8 weeks after injury and 47 healthy control (HC) participants. They were assessed with the Symbol Digit Modality Test, an n-back task and a rate of gain of information choice reaction time task that conforms to Hick's law. Participants were also assessed with measures of fatigue and psychological status. RESULTS: as expected, findings revealed no group differences on simple reaction time tasks, but as task complexity increased, the mTBI group performed more slowly than the HC group. This group difference occurred independently of fatigue and psychological distress levels and was associated with a moderate effect size. CONCLUSIONS: during the subacute period after mTBI, premorbidly healthy individuals demonstrate impairment in their ability to rapidly process information as the cognitive load of the task increases beyond simple reaction time requirements. Examination of whether these changes affect resumption of premorbid roles is warranted.

An observational study of the association between sleep disturbance, fatigue and cognition in the post-acute period after mild traumatic brain injury in prospectively studied premorbidly healthy adults.

The literature examining the relationship between sleep disturbance, fatigue, and cognition in premorbidly healthy civilian adults after mTBI is very limited. The current study aimed to investigate the relationships of sleep disturbance and fatigue with cognition while controlling for psychological distress and age. Using a prospective observational design, we assessed 60 premorbidly healthy individuals approximately 8 weeks after mTBI. Participants were assessed with the Pittsburgh Sleep Quality Index and the Multidimensional Fatigue Inventory as well as measures of speed of information processing, attention, memory, and executive function; depression and anxiety were also assessed. Findings revealed associations between sleep disturbance and cognition (r2 = .586, p < .001) as well as between fatigue and cognition (r2 = .390, p < .01), independent of the impact of psychological status and age. Associations were evident in the domains of processing speed, attention, and memory, but were most consistently apparent on measures of executive function. Greater sleep disturbance was most consistently associated with poorer cognitive function. Unexpectedly, higher levels of fatigue were associated with better cognitive function, which may be explained by the coping hypothesis. Given sleep interventions have been shown to improve sleep disturbance, these findings suggest that sleep intervention may also result in improved cognition after mTBI.

Investigating White Matter Tract Microstructural Changes at Six-Twelve Weeks following Mild Traumatic Brain Injury: A Combined Diffusion Tensor Imaging and Neurite Orientation Dispersion and Density Imaging Study.

Using diffusion-weighted imaging (DWI), research has demonstrated changes suggestive of damage to white matter tracts (WMT) following mild traumatic brain injury (mTBI). Yet due to the predominant use of the diffusion tensor imaging (DTI) model, which has numerous well-established limitations, it has not yet been possible to clearly examine the nature of changes to WMT microstructure following mTBI. This study used a second DWI-based technique, neurite orientation dispersion and density imaging (NODDI), in combination with DTI to measure microstructural changes within the corpus callosum, three long association and one projection WMTs at 6-12 weeks following mTBI, compared with matched trauma controls (TC). Between-groups differences were identified across all WMT for the DTI metric fractional anisotropy (FA), and the NODDI metrics orientation dispersion index (ODI) and isotropic volume fraction (ISO). No statistically significant between-groups differences were found for other DTI and NODDI metrics. Our study revealed that reduced FA was accompanied by increased ODI, suggesting that mTBI results in reduced coherence of axonal fiber bundles within the studied WMTs. These between-groups differences in WMT microstructure were found at 6-12 weeks post-injury, which suggests that structural recovery is not yet complete towards end of the typical 3-month recovery period.

Associations between coping style, illness perceptions and self-reported symptoms after mild traumatic brain injury in prospectively studied pre-morbidly healthy individuals.

This study investigated whether coping style and/or illness perceptions are related to the severity of self-reported post-concussion syndrome (PCS) symptoms in the post-acute period after mild traumatic brain injury (mTBI). We hypothesised that reporting of early and late enduring-type PCS symptomatology (self-reported symptoms) would be significantly and negatively associated with: (a) an active "approach" coping style and (b) the belief that the injury would have negative consequences on the respondent's life. Using a prospective observational design we assessed 61 pre-morbidly healthy individuals who were admitted to hospital after an mTBI. Participants were assessed with measures of coping style and illness perception as well as PCS, depressive, anxiety and post-traumatic stress symptomatology. After controlling for current psychological distress, approach coping style significantly and independently predicted the severity of self-reported symptoms for early-type PCS symptomatology, but not late enduring-type PCS symptoms. The extent to which the respondent believed their symptoms were due to the mTBI significantly and independently predicted both early and late enduring-type PCS symptoms. This study indicates that different patterns of coping and illness perceptions are associated with early vs. late enduring types of PCS symptoms; this may have implications for the treatment of post-injury self-reported symptoms.

The association between pain type, cognition and complaint after mild traumatic brain injury in prospectively studied premorbidly healthy adults admitted to hospital.

OBJECTIVE: Literature examining the relationship between pain, cognition, and complaint after mild traumatic brain injury (mTBI) has conceptualized and measured pain as a unitary construct. Pain is defined as being multidimensional, however, with both sensory and affective aspects. The current study aimed to determine whether the sensory and affective aspects of pain differentially relate to cognition and complaint. METHOD: Using a prospective observational design, 6-10 weeks after injury, we assessed 60 premorbidly healthy individuals, who were admitted to hospital after an mTBI. Participants were assessed with multidimensional and unitary pain questionnaires, as well as measures of cognition, complaint, anxiety and depression. RESULTS: Findings showed that a univariate measure of pain did not successfully measure affective pain. Multidimensional pain assessment revealed that affective descriptors of pain were significantly and independently associated with aspects of cognitive function (p < .05). A number of sensory types of pain also significantly related to cognition (p < .05), with these relationships varying between the different sensory pain types. Continuous type sensory pain also independently predicted memory and executive function. No independent linear relationships were evident between any type of pain and level of complaint. CONCLUSIONS: These findings show for the first time that it is important to examine both affective and sensory aspects of pain in individuals after mTBI, as pain subtypes show differential relationships with cognition. The study also suggests that the relationship between pain and complaint is not an independent one. This study has implications for treatment and management of individuals experiencing cognitive difficulties after mTBI. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Prospective Characterization of Cognitive Function in Typical and 'Brainstem Predominant'Progressive Supranuclear Palsy Phenotypes.

OBJECTIVE: Clinicopathological studies over the last decade have broadened the clinical spectrum of progressive supranuclear palsy (PSP) to include several distinct clinical syndromes. We examined the cognitive profiles of patients with PSP-Richardson's syndrome (PSP-RS) and two atypical 'brainstem predominant' PSP phenotypes (PSP-parkinsonism, PSP-P; and PSP-pure akinesia with gait freezing, PSP-PAGF) using a comprehensive neuropsychological battery. METHODS: Fourteen patients diagnosed as PSP-RS, three patients with PSP-P and four patients with PSP-PAGF were assessed using a comprehensive battery of neuropsychological tests. RESULTS: The typical PSP-RS subgroup demonstrated greater impairments in processing speed [t(19) = -4.10, p = 0.001 (d =1.66)] and executive function [t(19) = -2.63, p = 0.02 (d = 1.20)] compared to the 'brainstem predominant' PSP phenotype. CONCLUSION: This is the first prospective study to demonstrate that PSP-RS and 'brainstem predominant' PSP phenotypes can be differentiated on cognitive grounds. These differences correspond with variations in pathological profiles reported in the literature.

White matter abnormalities and impaired attention abilities in children born very preterm.

While attention impairments are commonly observed in very preterm (<32weeks' gestational age) children, neuroanatomical correlates of these difficulties are unclear. We aimed to determine whether the microstructural organization of key white matter tracts thought to be involved in attention (cingulum bundle, superior longitudinal fasciculi, reticular activating system, and corpus callosum) were altered in very preterm children compared with term-born controls. We also aimed to determine whether alterations in microstructural organization of these tracts were associated with attention functioning in very preterm children. One hundred and forty-nine very preterm children and 36 term-born controls underwent neuroimaging and assessment of their attention abilities at 7years. Constrained spherical deconvolution and probabilistic tractography was used to identify the key white matter tracts. Altered microstructural organization and reduced tract volume within reticular activating system and corpus callosum were found in the very preterm group compared with the control group. Diffusion and volume changes in the cingulum bundle, superior longitudinal fasciculi, reticular activating system, and corpus callosum were related to variations in attention functioning in the very preterm children. These findings emphasize that white matter tract integrity is associated with later attentional abilities in very preterm children.

Frontal deficits differentiate progressive supranuclear palsy from Parkinson's disease.

The clinical differentiation of progressive supranuclear palsy from Parkinson's disease can be challenging, due to overlapping clinical features and a lack of diagnostic markers. Abnormalities in cognitive function form part of the clinical spectrums of these diseases and distinctive cognitive profiles may be helpful in differentiating these diseases in the diagnostic period. A comprehensive neuropsychological test battery was administered to 12 patients with clinically diagnosed progressive supranuclear palsy and 12 patients with Parkinson's disease matched for age and disease duration. Effect size (Cohen's d) was calculated for cognitive tests that were significantly different between groups. Patients with progressive supranuclear palsy performed significantly worse than those with Parkinson's disease on measures of processing speed, verbal fluency, planning, verbal abstract reasoning, verbal memory, and made more perseverative responses on a set shifting task. Measures of executive function, manual dexterity and processing speed were most diagnostically useful (Cohen's d > 2.0) in differentiating between progressive supranuclear palsy and Parkinson's disease. These findings suggest that more severe and prominent 'frontal' cognitive deficits in patients with progressive parkinsonism would be helpful in predicting progressive supranuclear palsy rather than Parkinson's disease and these findings may contribute to the development of diagnostic criteria.

Individual differences in retrieval-induced forgetting affect the impact of frontal dysfunction on retrieval-induced forgetting.

INTRODUCTION: Retrieval-induced forgetting (RIF) paradigms are used to investigate successful forgetting of irrelevant information. Responses to the RIF paradigm can vary substantially, but to date there has been limited investigation of the individual difference factors that contribute to RIF performances. This study investigated whether individual differences in baseline RIF ability impacted on RIF performance after temporarily induced frontal dysfunction. To examine this question, left dorsolateral prefrontal cortex (DLPFC) function was temporarily reduced using transcranial direct current stimulation (tDCS). METHOD: Fourteen individuals received tDCS (sham/active) on two separate occasions and completed a RIF paradigm within 30 minutes of receiving tDCS. RESULTS: As expected, the group of individuals who demonstrated high levels of RIF after sham tDCS demonstrated a significant reduction in RIF performance after active tDCS. Unexpectedly, however, those individuals who demonstrated low or reverse RIF effects after sham tDCS showed a significant increase in RIF after active tDCS. CONCLUSIONS: This is the first study to show that individual differences in premorbid RIF affect RIF performance after temporary reduction in left DLPFC function. These findings suggest that premorbid RIF ability may be an important factor to consider when investigating the impact of frontal dysfunction on RIF in patient populations.

Neonatal brain pathology predicts adverse attention and processing speed outcomes in very preterm and/or very low birth weight children.

OBJECTIVE: This study aimed to examine attention and processing speed outcomes in very preterm (VPT; < 32 weeks' gestational age) or very low birth weight (VLBW; < 1,500 g) children, and to determine whether brain abnormality measured by neonatal MRI can be used to predict outcome in these domains. METHOD: A cohort of 198 children born < 30 weeks' gestational age and/or < 1,250 g and 70 term controls were examined. Neonatal MRI scans at term equivalent age were quantitatively assessed for white matter, cortical gray matter, deep gray matter, and cerebellar abnormalities. Attention and processing speed were assessed at 7 years using standardized neuropsychological tests. Group differences were tested in attention and processing speed, and the relationships between these cognitive domains and brain abnormalities at birth were investigated. RESULTS: At 7 years of age, the VPT/VLBW group performed significantly poorer than term controls on all attention and processing speed outcomes. Associations between adverse attention and processing speed performances at 7 years and higher neonatal brain abnormality scores were found; in particular, white matter and deep gray matter abnormalities were reasonable predictors of long-term cognitive outcomes. CONCLUSION: Attention and processing speed are significant areas of concern in VPT/VLBW children. This is the first study to show that adverse attention and processing speed outcomes at 7 years are associated with neonatal brain pathology.

Neuropsychological outcomes of stereotactic radiotherapy for cerebral arteriovenous malformations.

To our knowledge, this is the first study to investigate cognitive outcome in patients with large or surgically inaccessible cerebral arteriovenous malformations (AVMs), who were treated with hypo-fractionated stereotactic radiotherapy (HSRT). A sample of 10 patients with AVMs was assessed up to 3.5 years post-HSRT. All patients were treated with HSRT to a total dose of 55 Gy in 11 fractions over a treatment period of 2.5 weeks. Neuropsychological assessments were given prior to radiotherapy and then at three time points following radiotherapy: 6 weeks, 6 months and 2.5-3.5 years post-treatment. The cognitive domains of attention, processing speed, learning, memory, semantic processing, naming, verbal fluency, visuospatial and executive function were assessed. Findings revealed that prior to radiotherapy the patient group was impaired in five of the nine cognitive domains. Post-treatment performances remained stable in the majority of domains; however, there was some fluctuation in semantic processing and memory performances. At 6 weeks post-treatment, a mild decrement was found in semantic processing ability; however, restoration to baseline levels was observed from 6 months onwards. At 2.5-3.5 years post-treatment, improvement was seen in the cohort's ability to remember new information when performances were compared with earlier time points. This study demonstrated improvements in memory several years after HSRT treatment. Further, this form of treatment was not associated with long-term, harmful cognitive side effects for these 10 patients encouraging further study of this treatment method. Further evaluation of the entire cohort is required to assess efficacy in terms of AVM obliteration and other potential side effects.