Browsing by Author "Tripodis, Yorghos"

Now showing 1 - 3 of 3
  • Thumbnail Image
    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 Medicine
    Objective: 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.
  • Thumbnail Image
    Item
    Traumatic brain injury and cognitive resilience in the Framingham Heart Study
    (Wiley, 2025-01-09) Hwang, Phillip H.; Durape, Shruti; Price, Eden; Gurnani, Ashita S.; Ang, Ting Fang Alvin; Devine, Sherral A.; Choi, Seo-Eun; Lee, Michael L.; Scollard, Phoebe; Gibbons, Laura E.; Mukherjee, Shubhabrata; Trittschuh, Emily H.; Sherva, Richard; Dumitrescu, Logan C.; Hohman, Timothy J.; Saykin, Andrew J.; Crane, Paul K.; Tripodis, Yorghos; Alosco, Michael L.; Katz, Douglas I.; Dams-O'Connor, Kristen; Au, Rhoda; Farrer, Lindsay A.; Mez, Jesse; Radiology and Imaging Sciences, School of Medicine
    Background: Some evidence supports an association between traumatic brain injury (TBI) and greater risk of dementia, but the role of cognitive resilience in this association is poorly understood. Method: 2,050 participants from the Framingham Heart Study Offspring cohort who were aged ≥60 year and had a plasma total tau (t‐tau) measure at Exam 8 (2005‐2008), and a neuropsychological (NP) exam visit within five years were included. Plasma t‐tau was measured using the Simoa assay (Quanterix). NP factor scores were previously derived for memory, language, and executive function using confirmatory factor analysis. Information on TBIs was collected by comprehensive review of medical records, health history updates, exams, and self‐report. TBI occurrence and severity were operationalized using modified ACRM & VA/DoD criteria, respectively. Cognitive resilience was operationalized using a residual approach by regressing each NP factor score on the plasma t‐tau measure, adjusting for age at Exam 8, sex, education, time from blood draw, and APOE ε4 genotype. The adjusted residuals were then regressed on history of TBI (yes versus no), and severity of TBI (moderate‐to‐severe versus mild versus none). Result: The sample was, on average, 67 years of age at Exam 8, 54% female, and college educated. No differences were observed in plasma t‐tau levels between those with and without TBI. Having a history of TBI was significantly associated with a reduction in resilience in executive function (β: ‐0.110; 95% CI: ‐0.175, ‐0.044; p: 0.001) as compared to not having a history of TBI. No significant associations were observed between history of TBI and resilience in memory or language. Greater TBI severity was significantly associated with worse resilience in executive function in a dose‐response manner (Ptrend: <0.001), with the association being strongest in the moderate‐to‐severe TBI group (β: ‐0.209; 95% CI: ‐0.340, ‐0.078; p: 0.002) followed by the mild TBI group (β: ‐0.082; 95% CI: ‐0.155, ‐0.010; p: 0.026). Conclusion: Having a TBI was associated with worse resilience to neurodegeneration in executive function, and most strongly among individuals with moderate‐to‐severe TBI. These results suggest that having a TBI may increase vulnerability to late‐life executive dysfunction after accounting for a primary neurodegenerative disease process.
  • Thumbnail Image
    Item
    White Matter Microstructure Is Associated with Serum Neuroactive Steroids and Psychological Functioning
    (Mary Ann Liebert, 2023) Umminger, Lisa F.; Rojczyk, Philine; Seitz-Holland, Johanna; Sollmann, Nico; Kaufmann, Elisabeth; Kinzel, Philipp; Zhang, Fan; Kochsiek, Janna; Langhein, Mina; Kim, Cara L.; Wiegand, Tim L. T.; Kilts, Jason D.; Naylor, Jennifer C.; Grant, Gerald A.; Rathi, Yogesh; Coleman, Michael J.; Bouix, Sylvain; Tripodis, Yorghos; Pasternak, Ofer; George, Mark S.; McAllister, Thomas W.; Zafonte, Ross; Stein, Murray B.; O'Donnell, Lauren J.; Marx, Christine E.; Shenton, Martha E.; Koerte, Inga K.; Psychiatry, School of Medicine
    Military service members are at increased risk for mental health issues, and comorbidity with mild traumatic brain injury (mTBI) is common. Largely overlapping symptoms between conditions suggest a shared pathophysiology. The present work investigates the associations among white matter microstructure, psychological functioning, and serum neuroactive steroids that are part of the stress-response system. Diffusion-weighted brain imaging was acquired from 163 participants (with and without military affiliation) and free-water-corrected fractional anisotropy (FAT) was extracted. Associations between serum neurosteroid levels of allopregnanolone (ALLO) and pregnenolone (PREGNE), psychological functioning, and whole-brain white matter microstructure were assessed using regression models. Moderation models tested the effect of mTBI and comorbid post-traumatic stress disorder (PTSD) and mTBI on these associations. ALLO is associated with whole-brain white matter FAT (β = 0.24, t = 3.05, p = 0.006). This association is significantly modulated by PTSD+mTBI comorbidity (β = 0.00, t = 2.50, p = 0.027), although an mTBI diagnosis alone did not significantly impact this association (p = 0.088). There was no significant association between PREGNE and FAT (p = 0.380). Importantly, lower FAT is associated with poor psychological functioning (β = -0.19, t = -2.35, p = 0.020). This study provides novel insight into a potential common pathophysiological mechanism of neurosteroid dysregulation underlying the high risk for mental health issues in military service members. Further, comorbidity of PTSD and mTBI may bring the compensatory effects of the brain's stress response to their limit. Future research is needed to investigate whether neurosteroid regulation may be a promising tool for restoring brain health and improving psychological functioning.