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Browsing by Author "Zafonte, Ross D."
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Item Age‐dependent white matter disruptions after military traumatic brain injury: Multivariate analysis results from ENIGMA brain injury(Wiley, 2022) Bouchard, Heather C.; Sun, Delin; Dennis, Emily L.; Newsome, Mary R.; Disner, Seth G.; Elman, Jeremy; Silva, Annelise; Velez, Carmen; Irimia, Andrei; Davenport, Nicholas D.; Sponheim, Scott R.; Franz, Carol E.; Kremen, William S.; Coleman, Michael J.; Williams, M. Wright; Geuze, Elbert; Koerte, Inga K.; Shenton, Martha E.; Adamson, Maheen M.; Coimbra, Raul; Grant, Gerald; Shutter, Lori; George, Mark S.; Zafonte, Ross D.; McAllister, Thomas W.; Stein, Murray B.; Thompson, Paul M.; Wilde, Elisabeth A.; Tate, David F.; Sotiras, Aristeidis; Morey, Rajendra A.; Psychiatry, School of MedicineMild Traumatic brain injury (mTBI) is a signature wound in military personnel, and repetitive mTBI has been linked to age‐related neurogenerative disorders that affect white matter (WM) in the brain. However, findings of injury to specific WM tracts have been variable and inconsistent. This may be due to the heterogeneity of mechanisms, etiology, and comorbid disorders related to mTBI. Non‐negative matrix factorization (NMF) is a data‐driven approach that detects covarying patterns (components) within high‐dimensional data. We applied NMF to diffusion imaging data from military Veterans with and without a self‐reported TBI history. NMF identified 12 independent components derived from fractional anisotropy (FA) in a large dataset (n = 1,475) gathered through the ENIGMA (Enhancing Neuroimaging Genetics through Meta‐Analysis) Military Brain Injury working group. Regressions were used to examine TBI‐ and mTBI‐related associations in NMF‐derived components while adjusting for age, sex, post‐traumatic stress disorder, depression, and data acquisition site/scanner. We found significantly stronger age‐dependent effects of lower FA in Veterans with TBI than Veterans without in four components (q < 0.05), which are spatially unconstrained by traditionally defined WM tracts. One component, occupying the most peripheral location, exhibited significantly stronger age‐dependent differences in Veterans with mTBI. We found NMF to be powerful and effective in detecting covarying patterns of FA associated with mTBI by applying standard parametric regression modeling. Our results highlight patterns of WM alteration that are differentially affected by TBI and mTBI in younger compared to older military Veterans.Item Amantadine Did Not Positively Impact Cognition in Chronic Traumatic Brain Injury: A Multi-Site, Randomized, Controlled Trial(Mary Ann Liebert, 2018-10-01) Hammond, Flora M.; Sherer, Mark; Malec, James F.; Zafonte, Ross D.; Dikmen, Sureyya; Bogner, Jennifer; Bell, Kathleen R.; Barber, Jason; Temkin, Nancy; Physical Medicine and Rehabilitation, School of MedicineDespite limited evidence to support the use of amantadine to enhance cognitive function after traumatic brain injury (TBI), the clinical use for this purpose is highly prevalent and is often based on inferred belief systems. The aim of this study was to assess effect of amantadine on cognition among individuals with a history of TBI and behavioral disturbance using a parallel-group, randomized, double-blind, placebo-controlled trial of amantadine 100 mg twice-daily versus placebo for 60 days. Included in the study were 119 individuals with two or more neuropsychological measures greater than 1 standard deviation below normative means from a larger study of 168 individuals with chronic TBI (>6 months post-injury) and irritability. Cognitive function was measured at treatment days 0, 28, and 60 with a battery of neuropsychological tests. Composite indices were generated: General Cognitive Index (included all measures), a Learning Memory Index (learning/memory measures), and Attention/Processing Speed Index (attention and executive function measures). Repeated-measures analysis of variance revealed statistically significant between-group differences favoring the placebo group at day 28 for General Cognitive Index (p = 0.002) and Learning Memory Index (p = 0.001), but not Attention/Processing Speed Index (p = 0.25), whereas no statistically significant between-group differences were found at day 60. There were no statistically significant between-group differences on adverse events. Cognitive function in individuals with chronic TBI is not improved by amantadine 100 mg twice-daily. In the first 28 days of use, amantadine may impede cognitive processing. However, the effect size was small and mean scores for both groups were generally within expectations for persons with history of complicated mild-to-severe TBI, suggesting that changes observed across assessments may not have functional significance. The use of amantadine to enhance cognitive function is not supported by these findings.Item Amantadine effect on perceptions of irritability after traumatic brain injury: results of the amantadine irritability multisite study(Mary Ann Liebert, Inc., 2015-08-15) Hammond, Flora M.; Sherer, Mark; Malec, James F.; Zafonte, Ross D.; Whitney, Marybeth; Bell, Kathleen; Dikmen, Sureyya; Bogner, Jennifer; Mysiw, Jerry; Pershad, Rashmi; Physical Medicine and Rehabilitation, School of MedicineThis study examines the effect of amantadine on irritability in persons in the post-acute period after traumatic brain injury (TBI). There were 168 persons ≥6 months post-TBI with irritability who were enrolled in a parallel-group, randomized, double-blind, placebo-controlled trial receiving either amantadine 100 mg twice daily or equivalent placebo for 60 days. Subjects were assessed at baseline and days 28 (primary end-point) and 60 of treatment using observer-rated and participant-rated Neuropsychiatric Inventory (NPI-I) Most Problematic item (primary outcome), NPI Most Aberrant item, and NPI-I Distress Scores, as well as physician-rated Clinical Global Impressions (CGI) scale. Observer ratings between the two groups were not statistically significantly different at day 28 or 60; however, observers rated the majority in both groups as having improved at both intervals. Participant ratings for day 60 demonstrated improvements in both groups with greater improvement in the amantadine group on NPI-I Most Problematic (p<0.04) and NPI-I Distress (p<0.04). These results were not significant with correction for multiple comparisons. CGI demonstrated greater improvement for amantadine than the placebo group (p<0.04). Adverse event occurrence did not differ between the two groups. While observers in both groups reported large improvements, significant group differences were not found for the primary outcome (observer ratings) at either day 28 or 60. This large placebo or nonspecific effect may have masked detection of a treatment effect. The result of this study of amantadine 100 mg every morning and noon to reduce irritability was not positive from the observer perspective, although there are indications of improvement at day 60 from the perspective of persons with TBI and clinicians that may warrant further investigation.Item Comparison of Common Outcome Measures for Assessing Independence in Patients Diagnosed with Disorders of Consciousness: A Traumatic Brain Injury Model Systems Study(Mary Ann Liebert, 2022) Snider, Samuel B.; Kowalski, Robert G.; Hammond, Flora M.; Izzy, Saef; Shih, Shirley L.; Rovito, Craig; Edlow, Brian L.; Zafonte, Ross D.; Giacino, Joseph T.; Bodien, Yelena G.; Physical Medicine and Rehabilitation, School of MedicinePatients with disorders of consciousness (DoC) after traumatic brain injury (TBI) recover to varying degrees of functional dependency. Dependency is difficult to measure but critical for interpreting clinical trial outcomes and prognostic counseling. In participants with DoC (i.e., not following commands) enrolled in the TBI Model Systems National Database (TBIMS NDB), we used the Functional Independence Measure (FIM®) as the reference to evaluate how accurately the Glasgow Outcome Scale-Extended (GOSE) and Disability Rating Scale (DRS) assess dependency. Using the established FIM-dependency cut-point of <80, we measured the classification performance of literature-derived GOSE and DRS cut-points at 1-year post-injury. We compared the area under the receiver operating characteristic curve (AUROC) between the DRSDepend, a DRS-derived marker of dependency, and the data-derived optimal GOSE and DRS cut-points. Of 18,486 TBIMS participants, 1483 met inclusion criteria (mean [standard deviation (SD)] age = 38 [18] years; 76% male). The sensitivity of GOSE cut-points of ≤3 and ≤4 (Lower Severe and Upper Severe Disability, respectively) for identifying FIM-dependency were 97% and 98%, but specificities were 73% and 51%, respectively. The sensitivity of the DRS cut-point of ≥12 (Severe Disability) for identifying FIM-dependency was 60%, but specificity was 100%. The DRSDepend had a sensitivity of 83% and a specificity of 94% for classifying FIM-dependency, with a greater AUROC than the data-derived optimal GOSE (≤3, p = 0.01) and DRS (≥10, p = 0.008) cut-points. Commonly used GOSE and DRS cut-points have limited specificity or sensitivity for identifying functional dependency. The DRSDepend identifies FIM-dependency more accurately than the GOSE and DRS cut-points, but requires further validation.Item Disorders of Consciousness due to Traumatic Brain Injury: Functional Status Ten Years Post-Injury(Mary Ann Liebert, 2018-09-18) Hammond, Flora M.; Giacino, Joseph T.; Nakase Richardson, Risa; Sherer, Mark; Zafonte, Ross D.; Whyte, John; Arciniegas, David B.; Tang, Xinyu; Physical Medicine and Rehabilitation, School of MedicineFew studies have assessed the long-term functional outcomes of patients with a disorder of consciousness due to traumatic brain injury (TBI). This study examined functional status during the first 10 years after TBI among a cohort with disorders of consciousness (i.e., coma, vegetative state, minimally conscious state). The study sample included 110 individuals with TBI who were unable to follow commands prior to inpatient rehabilitation and for whom follow-up data were available at 1, 2, 5, and 10 years post-injury. The sample was subdivided into those who demonstrated command-following early (before 28 days post-injury) versus late (≥ 28 days post-injury or never). Functional Independence Measure (FIM) at 1, 2, 5, and 10 years following TBI was used to measure functional outcomes. Measureable functional recovery occurred throughout the 10-year period, with more than two thirds of the sample achieving independence in mobility and self-care, and about one quarter achieving independent cognitive function by 10 years. Following commands prior to 28 days was associated with greater functional independence at all outcome time-points. Multi-trajectory modeling of recovery of three FIM subscales (self-care, mobility, cognition) revealed four distinct prognostic groups with different temporal patterns of change on these subscales. More than half the sample achieved near-maximal recovery by 1 year post-injury, while the later command-following subgroups recovered over longer periods of time. Significant late functional decline was not observed in this cohort. Among a cohort of patients unable to follow commands at the time of inpatient rehabilitation, a substantial proportion achieved functional independence in self-care, mobility, and cognition. The proportion of participants achieving functional independence increased between 5 and 10 years post-injury. These findings suggest that individuals with disorders of consciousness may benefit from ongoing functional monitoring and updated care plans for at least the first decade after TBI.Item Distal and Proximal Predictors of Rehospitalization Over 10 Years Among Survivors of TBI: A National Institute on Disability, Independent Living, and Rehabilitation Research Traumatic Brain Injury Model Systems Study(Wolters Kluwer, 2023) Lercher, Kirk; Kumar, Raj G.; Hammond, Flora M.; Zafonte, Ross D.; Hoffman, Jeanne M.; Walker, William C.; Verduzco-Gutierrez, Monica; Dams-O’Connor, Kristen; Physical Medicine and Rehabilitation, School of MedicineObjective: To describe the rates and causes of rehospitalization over a 10-year period following a moderate-severe traumatic brain injury (TBI) utilizing the Healthcare Cost and Utilization Project (HCUP) diagnostic coding scheme. Setting: TBI Model Systems centers. Participants: Individuals 16 years and older with a primary diagnosis of TBI. Design: Prospective cohort study. Main measures: Rehospitalization (and reason for rehospitalization) as reported by participants or their proxies during follow-up telephone interviews at 1, 2, 5, and 10 years postinjury. Results: The greatest number of rehospitalizations occurred in the first year postinjury (23.4% of the sample), and the rates of rehospitalization remained stable (21.1%-20.9%) at 2 and 5 years postinjury and then decreased slightly (18.6%) at 10 years postinjury. Reasons for rehospitalization varied over time, but seizure was the most common reason at 1, 2, and 5 years postinjury. Other common reasons were related to need for procedures (eg, craniotomy or craniectomy) or medical comorbid conditions (eg, diseases of the heart, bacterial infections, or fractures). Multivariable logistic regression models showed that Functional Independence Measure (FIM) Motor score at time of discharge from inpatient rehabilitation was consistently associated with rehospitalization at all time points. Other factors associated with future rehospitalization over time included a history of rehospitalization, presence of seizures, need for craniotomy/craniectomy during acute hospitalization, as well as older age and greater physical and mental health comorbidities. Conclusion: Using diagnostic codes to characterize reasons for rehospitalization may facilitate identification of baseline (eg, FIM Motor score or craniotomy/craniectomy) and proximal (eg, seizures or prior rehospitalization) factors that are associated with rehospitalization. Information about reasons for rehospitalization can aid healthcare system planning. By identifying those recovering from TBI at a higher risk for rehospitalization, providing closer monitoring may help decrease the healthcare burden by preventing rehospitalization.Item Incidence and risk factors of posttraumatic seizures following traumatic brain injury: A Traumatic Brain Injury Model Systems Study(Wiley, 2016-12) Ritter, Anne C.; Wagner, Amy K.; Fabio, Anthony; Pugh, Mary Jo; Walker, William C.; Szaflarski, Jerzy P.; Zafonte, Ross D.; Brown, Allen W.; Hammond, Flora M.; Bushnik, Tamara; Johnson-Green, Douglas; Shea, Timothy; Krellman, Jason W.; Rosenthal, Joseph A.; Dreer, Laura E.; Department of Physical Medicine and Rehabilitation, School of MedicineObjective Determine incidence of posttraumatic seizure (PTS) following traumatic brain injury (TBI) among individuals with moderate-to-severe TBI requiring rehabilitation and surviving at least 5 years. Methods Using the prospective TBI Model Systems National Database, we calculated PTS incidence during acute hospitalization, and at years 1, 2, and 5 postinjury in a continuously followed cohort enrolled from 1989 to 2000 (n = 795). Incidence rates were stratified by risk factors, and adjusted relative risk (RR) was calculated. Late PTS associations with immediate (<24 h), early (24 h–7 day), or late seizures (>7 day) versus no seizure prior to discharge from acute hospitalization was also examined. Results PTS incidence during acute hospitalization was highest immediately (<24 h) post-TBI (8.9%). New onset PTS incidence was greatest between discharge from inpatient rehabilitation and year 1 (9.2%). Late PTS cumulative incidence from injury to year 1 was 11.9%, and reached 20.5% by year 5. Immediate/early PTS RR (2.04) was increased for those undergoing surgical evacuation procedures. Late PTS RR was significantly greater for individuals who self-identified as a race other than black/white (year 1 RR = 2.22), and for black individuals (year 5 RR = 3.02) versus white individuals. Late PTS was greater for individuals with subarachnoid hemorrhage (year 1 RR = 2.06) and individuals age 23–32 (year 5 RR = 2.43) and 33–44 (year 5 RR = 3.02). Late PTS RR years 1 and 5 was significantly higher for those undergoing surgical evacuation procedures (RR: 3.05 and 2.72, respectively). Significance In this prospective, longitudinal, observational study, PTS incidence was similar to that in studies published previously. Individuals with immediate/late seizures during acute hospitalization have increased late PTS risk. Race, intracranial pathologies, and neurosurgical procedures also influenced PTS RR. Further studies are needed to examine the impact of seizure prophylaxis in high-risk subgroups and to delineate contributors to race/age associations on long-term seizure outcomes.Item Minimum Competency Recommendations for Programs That Provide Rehabilitation Services for Persons With Disorders of Consciousness: A Position Statement of the American Congress of Rehabilitation Medicine and the National Institute on Disability, Independent Living and Rehabilitation Research Traumatic Brain Injury Model Systems(Elsevier, 2020-02) Giacino, Joseph T.; Whyte, John; Nakase-Richardson, Risa; Katz, Douglas I.; Arciniegas, David B.; Blum, Sonja; Day, Kristin; Greenwald, Brian D.; Hammond, Flora M.; Pape, Theresa Bender; Rosenbaum, Amy; Seel, Ronald T.; Weintraub, Alan; Yablon, Stuart; Zafonte, Ross D.; Zasler, Nathan; Physical Medicine and Rehabilitation, School of MedicinePersons who have disorders of consciousness (DoC) require care from multidisciplinary teams with specialized training and expertise in management of the complex needs of this clinical population. The recent promulgation of practice guidelines for patients with prolonged DoC by the American Academy of Neurology, American Congress of Rehabilitation Medicine (ACRM), and National Institute on Disability, Independent Living, and Rehabilitation Research (NIDILRR) represents a major advance in the development of care standards in this area of brain injury rehabilitation. Implementation of these practice guidelines requires explication of the minimum competencies of clinical programs providing services to persons who have DoC. The Brain Injury Interdisciplinary Special Interest Group of the ACRM, in collaboration with the Disorders of Consciousness Special Interest Group of the NIDILRR-Traumatic Brain Injury Model Systems convened a multidisciplinary panel of experts to address this need through the present position statement. Content area-specific workgroups reviewed relevant peer-reviewed literature and drafted recommendations which were then evaluated by the expert panel using a modified Delphi voting process. The process yielded 21 recommendations on the structure and process of essential services required for effective DoC-focused rehabilitation, organized into 4 categories: diagnostic and prognostic assessment (4 recommendations), treatment (11 recommendations), transitioning care/long-term care needs (5 recommendations), and management of ethical issues (1 recommendation). With few exceptions, these recommendations focus on infrastructure requirements and operating procedures for the provision of DoC-focused neurorehabilitation services across subacute and postacute settings.Item National Institute of Neurological Disorders and Stroke Consensus Diagnostic Criteria for Traumatic Encephalopathy Syndrome(Wolters Kluwer, 2021) Katz, Douglas I.; Bernick, Charles; Dodick, David W.; Mez, Jesse; Mariani, Megan L.; Adler, Charles H.; Alosco, Michael L.; Balcer, Laura J.; Banks, Sarah J.; Barr, William B.; Brody, David L.; Cantu, Robert C.; Dams-O’Connor, Kristen; Geda, Yonas E.; Jordan, Barry D.; McAllister, Thomas W.; Peskind, Elaine R.; Petersen, Ronald C.; Wethe, Jennifer V.; Zafonte, Ross D.; Foley, Éimear M.; Babcock, Debra J.; Koroshetz, Walter J.; Tripodis, Yorghos; McKee, Ann C.; Shenton, Martha E.; Cummings, Jeffrey L.; Reiman, Eric M.; Stern, Robert A.; Psychiatry, School of MedicineObjective: To develop evidence-informed, expert consensus research diagnostic criteria for traumatic encephalopathy syndrome (TES), the clinical disorder associated with neuropathologically diagnosed chronic traumatic encephalopathy (CTE). Methods: A panel of 20 expert clinician-scientists in neurology, neuropsychology, psychiatry, neurosurgery, and physical medicine and rehabilitation, from 11 academic institutions, participated in a modified Delphi procedure to achieve consensus, initiated at the First National Institute of Neurological Disorders and Stroke Consensus Workshop to Define the Diagnostic Criteria for TES, April, 2019. Before consensus, panelists reviewed evidence from all published cases of CTE with neuropathologic confirmation, and they examined the predictive validity data on clinical features in relation to CTE pathology from a large clinicopathologic study (n = 298). Results: Consensus was achieved in 4 rounds of the Delphi procedure. Diagnosis of TES requires (1) substantial exposure to repetitive head impacts (RHIs) from contact sports, military service, or other causes; (2) core clinical features of cognitive impairment (in episodic memory and/or executive functioning) and/or neurobehavioral dysregulation; (3) a progressive course; and (4) that the clinical features are not fully accounted for by any other neurologic, psychiatric, or medical conditions. For those meeting criteria for TES, functional dependence is graded on 5 levels, ranging from independent to severe dementia. A provisional level of certainty for CTE pathology is determined based on specific RHI exposure thresholds, core clinical features, functional status, and additional supportive features, including delayed onset, motor signs, and psychiatric features. Conclusions: New consensus diagnostic criteria for TES were developed with a primary goal of facilitating future CTE research. These criteria will be revised as updated clinical and pathologic information and in vivo biomarkers become available.Item Neurocognitive markers of childhood abuse in individuals with PTSD: Findings from the INTRuST Clinical Consortium(Elsevier, 2020-02-01) Bomyea, Jessica; Simmons, Alan N.; Shenton, Martha E.; Coleman, Michael J.; Bouix, Sylvain; Rathi, Yogesh; Pasternak, Ofer; Coimbra, Raul; Shutter, Lori; George, Mark S.; Grant, Gerald; Zafonte, Ross D.; McAllister, Thomas W.; Stein, Murray B.; Psychiatry, School of MedicineTo date, few studies have evaluated the contribution of early life experiences to neurocognitive abnormalities observed in posttraumatic stress disorder (PTSD). Childhood maltreatment is common among individuals with PTSD and is thought to catalyze stress-related biobehavioral changes that might impact both brain structure and function in adulthood. The current study examined differences in brain morphology (brain volume, cortical thickness) and neuropsychological performance in individuals with PTSD characterized by low or high self-reported childhood maltreatment, compared with healthy comparison participants. Data were drawn from the INjury and TRaUmatic STress (INTRuST) Clinical Consortium imaging repository, which contains MRI and self-report data for individuals classified as PTSD positive (with and without a history of mild traumatic brain injury [mTBI]), individuals with mTBI only, and healthy comparison participants. The final sample included 36 individuals with PTSD without childhood maltreatment exposure (PTSD, n = 30 with mTBI), 31 individuals with PTSD and childhood maltreatment exposure (PTSD + M, n = 26 with mTBI), and 114 healthy comparison participants without history of childhood maltreatment exposure (HC). The PTSD + M and PTSD groups demonstrated cortical thinning in prefrontal and occipital regions, and poorer verbal memory and processing speed compared to the HC group. PTSD + M participants demonstrated cortical thinning in frontal and cingulate regions, and poorer executive functioning relative to the PTSD and HC groups. Thus, neurocognitive features varied between individuals with PTSD who did versus did not have exposure to childhood maltreatment, highlighting the need to assess developmental history of maltreatment when examining biomarkers in PTSD.