Brian L. Brooks

Tracking neuropsychological recovery following concussion in sport

Primary objective: The purpose of this study was to illustrate the serial use of computerized neuropsychological screening with ImPACT to monitor recovery in a clinical case series of injured athletes. Methods and procedures: Amateur athletes with concussions (n = 30, average age = 16.1, SD = 2.1 years) underwent pre-season testing and three post-concussion evaluations within the following intervals: 1–2 days, 3–7 days (M = 5.2 days) and 1–3 weeks (M = 10.3 days). The study selection criteria increased the probability of including athletes with slow recovery. Results: Repeated measures ANOVAs revealed significant main effects for all five composite scores (verbal memory, visual memory, reaction time, processing speed and total symptoms). In group analyses, performance decrements and symptoms relating to concussion appeared to largely resolve by 5 days post-injury and fully resolve by 10 days. Athletes’ scores were examined individually using the reliable change methodology. At 1 day post-injury, 90% had two or more reliable declines in performance or increases in symptom reporting. At 10 days, 37% were still showing two or more reliable changes from pre-season levels. Conclusions: This study illustrates the importance of analysing individual athletes’ test data because group analyses can obscure slow recovery in a substantial minority of athletes.

No cumulative effects for one or two previous concussions.

Background: Sports medicine clinicians and the general public are interested in the possible cumulative effects of concussion. Objective: To examine whether athletes with a history of one or two previous concussions differed in their preseason neuropsychological test performances or symptom reporting. Method: Participants were 867 male high school and university amateur athletes who completed preseason testing with ImPACT version 2.0. They were sorted into three groups on the basis of number of previous concussions. There were 664 athletes with no previous concussions, 149 with one previous concussion, and 54 with two previous concussions. Multivariate analysis of variance was conducted using the verbal memory, visual memory, reaction time, processing speed, and postconcussion symptom composite scores as dependent variables and group membership as the independent variable. Results: There was no significant multivariate effect, nor were there any significant main effects for individual scores. There was no measurable effect of one or two previous concussions on athletes’ preseason neuropsychological test performance or symptom reporting. Conclusion: If there is a cumulative effect of one or two previous concussions, it is very small and undetectable using this methodology.

“Good Old Days” Bias Following Mild Traumatic Brain Injury

A small percentage of people with a mild traumatic brain injury (MTBI) report persistent symptoms and problems many months or even years following injury. Preliminary research suggests that people who sustain an injury often underestimate past problems (i.e., “good old days” bias), which can impact their perceived level of current problems and recovery. The purpose of this study was to examine the influence of the good old bays bias on symptom reporting following MTBI. The MTBI sample consisted of 90 referrals to a concussion clinic (mean time from injury to evaluation = 2.1 months, SD = 1.5, range = 0.8–8.1). All were considered temporarily fully disabled from an MTBI and they were receiving financial compensation through the Workers Compensation system. Patients provided post-injury and pre-injury retrospective ratings on the 16-item British Columbia Post-concussion Symptom Inventory (BC-PSI). Ratings were compared to 177 healthy controls recruited from the community and a local university. Consistent with the good old bays bias, MTBI patients retrospectively endorsed the presence of fewer pre-injury symptoms compared to the control group. Individuals who failed effort testing tended to retrospectively report fewer symptoms pre-injury compared to those patients who passed effort testing. Many MTBI patients report their pre-injury functioning as better than the average person. This can negatively impact their perception of current problems, recovery from injury, and return to work.

Clinical Risk Score for Persistent Postconcussion Symptoms Among Children With Acute Concussion in the ED

IMPORTANCE Approximately one-third of children experiencing acute concussion experience ongoing somatic, cognitive, and psychological or behavioral symptoms, referred to as persistent postconcussion symptoms (PPCS). However, validated and pragmatic tools enabling clinicians to identify patients at risk for PPCS do not exist. OBJECTIVE To derive and validate a clinical risk score for PPCS among children presenting to the emergency department. DESIGN, SETTING, AND PARTICIPANTS Prospective, multicenter cohort study (Predicting and Preventing Postconcussive Problems in Pediatrics [5P]) enrolled young patients (aged 5-<18 years) who presented within 48 hours of an acute head injury at 1 of 9 pediatric emergency departments within the Pediatric Emergency Research Canada (PERC) network from August 2013 through September 2014 (derivation cohort) and from October 2014 through June 2015 (validation cohort). Participants completed follow-up 28 days after the injury. EXPOSURES All eligible patients had concussions consistent with the Zurich consensus diagnostic criteria. MAIN OUTCOMES AND MEASURES The primary outcome was PPCS risk score at 28 days, which was defined as 3 or more new or worsening symptoms using the patient-reported Postconcussion Symptom Inventory compared with recalled state of being prior to the injury. RESULTS In total, 3063 patients (median age, 12.0 years [interquartile range, 9.2-14.6 years]; 1205 [39.3%] girls) were enrolled (n = 2006 in the derivation cohort; n = 1057 in the validation cohort) and 2584 of whom (n = 1701 [85%] in the derivation cohort; n = 883 [84%] in the validation cohort) completed follow-up at 28 days after the injury. Persistent postconcussion symptoms were present in 801 patients (31.0%) (n = 510 [30.0%] in the derivation cohort and n = 291 [33.0%] in the validation cohort). The 12-point PPCS risk score model for the derivation cohort included the variables of female sex, age of 13 years or older, physician-diagnosed migraine history, prior concussion with symptoms lasting longer than 1 week, headache, sensitivity to noise, fatigue, answering questions slowly, and 4 or more errors on the Balance Error Scoring System tandem stance. The area under the curve was 0.71 (95% CI, 0.69-0.74) for the derivation cohort and 0.68 (95% CI, 0.65-0.72) for the validation cohort. CONCLUSIONS AND RELEVANCE A clinical risk score developed among children presenting to the emergency department with concussion and head injury within the previous 48 hours had modest discrimination to stratify PPCS risk at 28 days. Before this score is adopted in clinical practice, further research is needed for external validation, assessment of accuracy in an office setting, and determination of clinical utility.

Cognitive functioning in first episode psychosis: initial presentation

This first part of a longitudinal study examined the initial cognitive performance of 312 individuals who recently presented with a first episode (FE) of psychosis. All attend a comprehensive first episode program. Deficits on a wide range of cognitive tests were observed, suggesting impairment similar to that seen in those with an established schizophrenia illness. There was no evidence to support differences in cognition among the different schizophrenia spectrum diagnostic groups.

Potential for misclassification of mild cognitive impairment: A study of memory scores on the Wechsler Memory Scale-III in healthy older adults

The psychometric criterion of mild cognitive impairment (MCI) generally involves having an unusually low score on memory testing (i.e., -1.5 SDs). However, healthy older adults can obtain low scores, particularly when multiple memory measures are administered. In turn, there is a substantial risk of psychometrically misclassifying MCI in healthy older adults. This study examined the base rates of low memory scores in older adults (55-87 years; n = 550) from the Wechsler Memory Scale-Third Edition (WMS-III; Wechsler, 1997b) standardization sample. The WMS-III consists of four co-normed episodic memory tests (i.e., Logical Memory, Faces, Verbal Paired Associates, and Family Pictures) that yield eight age- and demographically-adjusted standard scores (Auditory Recognition and Working Memory tests not included). When the eight age-adjusted scores were examined simultaneously, 26% of older adults had one or more scores at or below the 5th percentile (i.e., -1.5 SDs). On the eight demographically- adjusted scores, 39% had at least one score at or below the 5th percentile. There was an inverse relationship between intellectual abilities and prevalence of low memory scores, particularly with the age-adjusted WMS-III scores. Understanding the base rates of low scores can reduce the overinterpretation of low memory scores and minimize false-positive misclassification.

NEPSY-II: A Developmental Neuropsychological Assessment, Second Edition

The NEPSY-II consists of 32 subtests for use in a neuropsychological assessment with preschoolers, children, and adolescents. This test review provides an overview of the NEPSY-II for clinicians and researchers, including descriptions of the subtests, changes from the original NEPSY, reliability and validity evidence, strengths, and limitations.

Substantial risk of “Accidental MCI” in healthy older adults: Base rates of low memory scores in neuropsychological assessment

When assessing older adults for mild cognitive impairment (MCI) or dementia, it is important to understand how often low memory scores are obtained in healthy people in order to minimize false positive diagnoses. This study examines the base rates of low memory scores in older adults across a battery of memory tests. Participants included older adults (55-79 years; N = 742) from the Neuropsychological Assessment Battery (NAB; Stern and White, 2003a) standardization sample. The NAB Memory Module consists of four co-normed memory tests (i.e., List Learning, Shape Learning, Story Learning, and Daily Living Memory) yielding 10 demographically corrected T-scores. When all 10 T-scores were examined simultaneously, 55.5% of older adults had one or more scores one standard deviation (SD) below the mean. At <1.5 SDs, 30.8% of healthy older adults obtained one or more low memory scores. Obtaining low memory scores occurs more often with lesser intellectual abilities. For example, 56.5% of older adults with low average intellectual abilities obtained one or more low memory scores (<1.5 SDs) compared to 21.1% with high average intellectual abilities. Understanding the base rates of low scores can reduce over-interpretation of isolated low memory scores and minimize false positive diagnoses of MCI.

Interview versus questionnaire symptom reporting in people with the postconcussion syndrome.

ObjectiveTo compare spontaneous, interview-based, postconcussion symptom reporting to endorsement of symptoms on a standardized questionnaire. ParticipantsSixty-one patients referred to a concussion clinic following mild traumatic brain injury. ProcedurePatients recalled their current symptoms and problems via open-ended interview and then completed a structured postconcussion checklist. Main Outcome MeasuresOpen-ended interview and the British Columbia Postconcussion Symptom Inventory (BC-PSI). ResultsOn average, patients endorsed 3.3 symptoms (SD = 1.9) during open-ended interview and 9.1 symptoms (SD = 3.2) on the BC-PSI (P < .001). Approximately 44% endorsed 4 or more symptoms during interview compared with 92% on the BC-PSI. The percentage of patients endorsing items on the BC-PSI compared with interview was significantly greater on all 13 items. It was common for patients to endorse symptoms as moderate-severe on the BC-PSI, despite not spontaneously reporting those symptoms during the interview. ConclusionsClinicians need to be cautious when interpreting questionnaires and be aware of the possibility of nonspecific symptom endorsement, symptom overendorsement, symptom expectations influencing symptom endorsement, and the nocebo effect.

Identifying a cognitive impairment subgroup in adults with mood disorders.

BACKGROUND We hypothesized that only a minority of patients with mood disorders have measurable cognitive impairment, and this minority drives the small-to-medium effect sizes detected in group studies. Removal of this minority from group statistical analyses will illustrate that the majority appear to have broadly normal cognitive functioning. METHODS Participants were adults between the ages of 20 and 54, including 659 healthy control subjects, 84 unmedicated outpatients diagnosed with depression, 59 outpatients diagnosed with depression who were on medications at the time of the evaluation, and 43 outpatients with bipolar disorder. All completed the CNS Vital Signs computerized cognitive screening battery. RESULTS The prevalence rates of low cognitive test scores were calculated for the healthy control subjects and the patients with mood disorders. Having two scores at or below the 5th percentile occurred in 31.2% of the patients and only 8.2% of the control subjects [χ(2)(1)=66.67, p<.0001; Odds Ratio=5.1, 95% CI=3.4-7.7]. For the control subjects, this low false positive rate for cognitive impairment was maintained across age groups, sexes, and education levels. A larger proportion of patients with bipolar disorder (41.9%) than patients with depression (27.1-28.6%) met this criterion for cognitive impairment. CONCLUSIONS This study suggests that cognitive impairment associated with mood disorders is limited to a minority of patients with the majority being broadly cognitively normal. Future research should determine if this identified subgroup has neuroanatomical, neurophysiological, or neuroendocrine abnormalities. Cognitive screening tools of this type might be useful in selecting participants for studies.