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The PRO ‐ AGE Tool and Its Association With Post Discharge Outcomes in Older Adults Admitted From the Emergency Department
Cohen, Inessa , Morinaga, Christian Valle , Han, Ling, Araujo, Katy, Avelino‐Silva, Thiago Junqueira , Bianco, Luann, Capelli, Sandra, Cruz, Daniel S. , Fishman, Ivy L., Gipson, Katrina, Gray, Elizabeth , Hung, William W. , Kang, Raymond , Lockhart, Mechelle, Ohuabunwa, Ugochi , Ottilie‐Kovelman, Sierra, Platts‐Mills, Timothy F. , Sandoval, Jacqueline , Sifnugel, Natalia, Taylor, Zachary , Tomasino, Debra F. , Vaughan, Camille P. , Hwang, Ula , Carpenter, Christopher R , Cruz, Daniel S , Ohuabunwa, Ugochi , Sandoval, Jacqueline , Vaughan, Camille P , Aliberti, Márlon J R , Hwang, Ula , Avelino-Silva, Thiago Junqueira , Curiati, Pedro Kallas , Gandhi, Tanish , Brandt, Cynthia , Carpenter, Christopher R. , Dresden, Scott M. , Hastings, Susan N. , Meeker, Daniella , Taylor, Zachary

Journal of the American Geriatrics Society | January 22, 2025 | Volume: 73 | Issue: 5 | Pages: 1419-1428

10.1111/jgs.19374 | PMID 39843218 Get It

ABSTRACT Background Existing risk scores assessing geriatric vulnerability in the emergency department (ED) have shown limited predictive power, especially in diverse populations. We investigated the relationship of a quick and easy‐to‐administer geriatric vulnerability scoring system with functional decline and mortality in older patients admitted to multiple hospitals through the ED in the United States (US) and Brazil (BR). Method Federated, international, multicenter observational study of hospitalized ED patients aged ≥ 65 from US and BR. The six criteria from the PRO‐AGE score (Physical impairment, Recent hospitalization, Older age [≥ 90], Acute mental alteration, Getting thinner, and Exhaustion; 0–8; higher scores = greater vulnerability) were assessed on admission. We used proportional hazards models to investigate the relationships between PRO‐AGE score groups and 90‐day mortality and functional decline, defined as new dependence in activities of daily living (ADL) and instrumental ADL (IADL), after adjusting for age, sex, race and ethnicity, education, Charlson comorbidity score, and study site. Death was considered a competing event for the functional decline outcome. Results A total of 1390 patients were included (US = 560; Brazil = 830). The 90‐day risk of death was higher for the upper compared with the lower (reference) PRO‐AGE group in both cohorts (US: HR = 11.76; 95% confidence interval [CI] = 2.56–54.04; BR: HR = 12.29; 95% CI = 3.54–42.59), whereas the risk of new 90‐day ADL disability was higher for upper (HR = 2.08; 95% CI = 1.21–3.56) and middle groups (HR = 2.10; 95% CI = 1.35–3.27) in the US but only the upper group in BR (HR = 1.70; 95% CI = 1.02–2.85). Conclusion A higher PRO‐AGE score was associated with mortality and functional decline in older ED patients admitted to hospitals in the US and BR, demonstrating its generalizability as a geriatric vulnerability risk score.
Medialized vs. Lateralized Reverse Total Shoulder Arthroplasty for Proximal Humerus Fractures
Holt, K., Bindi, Victoria E. , Buchanan, Timothy R. , Reddy, Akshay , Tishad, Abtahi , Desai, Persis , Hones, Keegan M. , Wright, Thomas W. , King, Joseph J. , Holt, Kara E , Reddy, Akshay R , Schoch, Bradley S , King, Joseph J , Hao, Kevin A , Hones, Keegan M , Schoch, Bradley S. , Hao, Kévin A.

JBJS Reviews | January 21, 2025 | Volume: 13 | Issue: 1 | Pages: No page available

10.2106/jbjs.rvw.24.00160 | PMID 39836775 Get It

Background: Reverse shoulder arthroplasty (RSA) is increasingly used in the treatment of proximal humerus fractures (PHFs) with reliable clinical improvement. Lateralized RSA implants have conferred superior outcomes compared with the original Grammont design in patients with nontraumatic indications. However, in the setting of a PHF, lateralized components can place increased tension across the tuberosity fracture site and potentially compromise tuberosity healing and outcomes. This systematic review and meta-analysis sought to determine the effect of implant design on clinical outcomes after RSA for PHFs. Methods: A systematic review was performed per Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed/MEDLINE, EMBASE, Web of Science, and Cochrane were queried for clinical studies on RSA performed for PHFs that reported implant manufacturer details. Our primary outcomes included postoperative external rotation (ER), forward elevation (FE), abduction, Constant score, rate of greater tuberosity (GT) healing, and the incidence of complications compared between medialized vs. lateralized global implant design. Results: Globally lateralized RSA cohorts (478 RSAs total with cumulative lateral offset achieved through humeral or glenoid lateralization or both humeral and glenoid lateralization) were found to have a greater mean postoperative Constant score compared with globally medialized (medialized glenoid and medialized humerus) RSA cohorts with 1,494 total medialized RSAs (66 vs. 59, p = 0.006), but there was no significant difference regarding mean postoperative ER (30° vs. 22°, p = 0.078), FE (117° vs. 119°, p = 0.708), or abduction (103° vs. 107°, p = 0.377). On meta-regression, neither implant design nor tuberosity status significantly influenced postoperative ER, FE, abduction, or Constant score on meta-regression independent of mean follow-up and age at surgery. The rate of GT healing was greater in lateralized compared with medialized RSAs (88% vs. 72%, p < 0.001). On meta-regression, medialized RSA design was associated with a 73% lower odds of GT healing (odds ratio = 0.27, 95% confidence interval = 0.11-0.68, p = 0.007) independent of mean follow-up and age at surgery. Conclusion: Lateralized RSA implants conferred no significant functional benefit over medialized implants when used in patients with PHFs. Level of Evidence: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.
Unilateral Versus Bilateral Endoscopic Resection of Olfactory Neuroblastoma: Pooled Analysis From Prospective and Retrospective Multicenter Data
Abiri, Arash , Nguyen, Theodore V. , Chen, Haidee , Krippaehne, Elise , Rahman, Arifeen S. , Roozdar, Pooya, Rosvall, Brandon R., Sabbaj, Michael , Adappa, Nithin D. , Chang, Eugene H., Chang, Michael T. , Kohanski, Michael A. , Hwang, Peter H. , Lee, Jivianne T. , Patel, Zara M. , Smith, Timothy L. , Storm, Phillip B. , Wang, Marilene B. , Krippaehne, Elise , Rahman, Arifeen S , Beswick, Daniel , Chang, Michael T , Choby, Garret , Eide, Jacob G. , Douglas, Jennifer E , Hwang, Peter H , Nayak, Jayakar V , Patel, Zara , Smith, Timothy L , Snyderman, Carl H , Wang, Eric W , Kuan, Edward C , Nguyen, Theodore V , Lerner, David K. , Workman, Alan D. , Wu, Shannon S. , Adappa, Nithin D. , Beswick, Daniel M. , Chang, Eugene H., Choby, Garret , Geltzeiler, Mathew , Le, Christopher H. , Nayak, Jayakar V. , Pinheiro‐Neto, Carlos , Resnick, Adam , John, Maie A. St. , Suh, Jeffrey D.

International Forum of Allergy & Rhinology | January 15, 2025 | Volume: 15 | Issue: 6 | Pages: 585-593

10.1002/alr.23531 | PMID 39811891 Get It

ABSTRACTBackgroundOlfactory neuroblastoma (ONB) is a rare sinonasal malignancy primarily treated with surgery. For tumors arising from the olfactory area, traditional treatment involves transcribriform resection of the anterior cranial fossa. Surgery can be performed with unilateral or bilateral resection depending on extent of involvement; however, there are currently no studies comparing outcomes between the two.MethodsProspective and retrospective data on primary ONB patients were collected from a multicenter registry involving eight academic sites. Propensity score matching (PSM) was used to create patient cohorts with similar baseline characteristics. Cox proportional hazards and Kaplan Meier analyses assessed overall survival (OS). Logistic regression assessed associations between extent of resection (unilateral versus bilateral) and tumor recurrence or postoperative cerebrospinal fluid (CSF) leak.ResultsA total of 187 ONB patients (47.6% female) with an average age of 53.6 ± 15.1 years were analyzed. Most tumors were unilateral (81.3%) and predominantly Kadish C (58.3%) or Hyams II (55.8%). Overall, 56.7% of patients underwent bilateral resection. Fifty‐four patients experienced tumor recurrence and nine had postoperative CSF leaks. Following PSM (n = 45/group), extent of resection was not associated with mortality (hazard ratio [HR] 1.73; p = 0.407) or OS (p = 0.400). There was no association between extent of resection and recurrence (odds ratio [OR] 0.90; p = 0.814) or postoperative CSF leak (OR 1.54; p = 0.647).ConclusionsFor ONB tumors where unilateral resection may be feasible and oncologically sound, the decision for unilateral versus bilateral resection showed no significant effect on survival, recurrence, or postoperative CSF leak. Oncologic outcomes may be comparable when resection is tailored to individual patient and tumor characteristics.
Clinical criteria for limbic‐predominant age‐related TDP‐43 encephalopathy
Nelson, Peter T. , Apostolova, Liana G. , Arfanakis, Konstantinos , Boyle, Patricia A. , Carlsson, Cynthia M. , Dacks, Penny A. , Domoto‐Reilly, Kimiko , Dugger, Brittany N. , Edelmayer, Rebecca M. , Grothe, Michel J. , Kawas, Claudia H. , Lee, Edward B., Lincoln, Karen D. , Maestre, Gladys E. , Mormino, Elizabeth C. , Onyike, Chiadi U. , Petersen, Ronald C. , Rabinovici, Gil D. , Rademakers, Rosa , Raman, Rema , Rascovsky, Katya, Rogalskı, Emily , Sperling, Reisa A., Yang, Hyun‐Sik , Corriveau-Lecavalier, Nick , Dugger, Brittany N , Domoto-Reilly, Kimiko , Rabinovici, Gil D , Grothe, Michel J , Dacks, Penny , Wolk, David A. , Corriveau‐Lecavalier, Nick , Dickerson, Bradford Clark , Fardo, David W. , Hohman, Timothy J. , Irwin, David J. , Jicha, Gregory A. , Jones, David T. , Rissman, Robert A. , Scheltens, Philip , Sperling, Reisa Anne , Yu, Lei , Zetterberg, Henrik , Schneider, Julie A.

Alzheimer's & Dementia | January 14, 2025 | Volume: 21 | Issue: 1 | Pages: No page available

10.1002/alz.14202 | PMID 39807681 Get It

Abstract Limbic predominant age‐related TDP‐43 encephalopathy neuropathologic change (LATE‐NC) is highly prevalent in late life and a common co‐pathology with Alzheimer's disease neuropathologic change (ADNC). LATE‐NC is a slowly progressive, amnestic clinical syndrome. Alternatively, when present with ADNC, LATE‐NC is associated with a more rapid course. With the emergence of anti‐amyloid therapeutics, discrimination of LATE‐NC from ADNC is critical and will lead to greater clinical recognition of amnestic patients without ADNC. Furthermore, co‐pathology with LATE‐NC may influence outcomes of these therapeutics. Thus there is a need to identify patients during life with likely LATE‐NC. We propose criteria for clinical diagnosis of LATE as an initial framework for further validation. In the context of progressive memory loss and substantial hippocampal atrophy, criteria are laid out for probable (amyloid negative) or possible LATE (amyloid biomarkers are unavailable or when amyloid is present, but hippocampal neurodegeneration is out of proportion to expected pure ADNC). Highlights Limbic‐predominant age‐related TDP‐43 encephalopathy (LATE) is a highly prevalent driver of neuropathologic memory loss in late life. LATE neuropathologic change (LATE‐NC) is a common co‐pathology with Alzheimer's disease neuropathologic change (ADNC) and may influence outcomes with emerging disease‐modifying medicines. We provide initial clinical criteria for diagnosing LATE during life either when LATE‐NC is the likely primary driver of symptoms or when observed in conjunction with AD. Definitions of possible and probable LATE are provided.
Longitudinal FDG-PET Metabolic Change Along the Lewy Body Continuum
Przybelski, Scott A. , Lesnick, Timothy G. , Diaz‐Galvan, Patricia , Murray, Melissa M., Nguyen, Aivi T. , Reichard, Ross R., Gunter, Jeffrey L. , Jack, Clifford R. , Min, Hoon‐Ki , Jain, Manoj , Miyagawa, Toji , Forsberg, Leah K. , Fields, Julie A. , Savica, Rodolfo , Graff-Radford, Jonathan, Knopman, David S., Graff‐Radford, Neill R. , Day, Gregory S. , Ferman, Tanis J. , Kremers, Walter K. , Petersen, Ronald C., Boeve, Bradley F., Lowe, Val J. , Kantarci, Kejal, Kantarci, Kejal , St Louis, Erik K, Min, Hoon-Ki Paul , Jack, Clifford R , Kantarci, Kejal , Day, Gregory S , Ferman, Tanis J , Nguyen, Aivi T , Diaz-Galvan, Patricia , Kremers, Walter K , Ferreira, Daniel , Schwarz, Christopher G. , Dickson, Dennis W. , Senjem, Matthew L. , Graff‐Radford, Jonathan , Ramanan, Vijay K. , Jones, David T., Botha, Hugo , Louis, Erik K. St. , Petersen, Ronald C. , Boeve, Bradley F.

JAMA Neurology | January 13, 2025 | Volume: 82 | Issue: 3 | Pages: 285

10.1001/jamaneurol.2024.4643 | PMID 39804619 Get It

Importance Although 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a well-established cross-sectional biomarker of brain metabolism in dementia with Lewy bodies (DLB), the longitudinal change in FDG-PET has not been characterized. Objective To investigate longitudinal FDG-PET in prodromal DLB and DLB, including a subsample with autopsy data, and report estimated sample sizes for a hypothetical clinical trial in DLB. Design, Setting, and Participants Longitudinal case-control study with mean (SD) follow-up of 3.8 (2.3) years. Cases were recruited consecutively between 2007 and 2022 at a referral center and among the population. Patients with probable DLB or mild cognitive impairment with Lewy bodies (MCI-LB) were included. Individuals without cognitive impairment were included from a population-based cohort balanced on age and sex for comparison. All participants completed at least 1 follow-up assessment by design. Exposure Patients with MCI-LB and DLB. Main Outcomes and Measures Rate of change in FDG-PET was assessed as standardized uptake value ratios (SUVr). Clinical progression was assessed with the Clinical Dementia Rating Sum of Boxes (CDR-SB) score. Results Thirty-five patients with probable DLB, 37 patients with MCI-LB, and 100 individuals without cognitive impairment were included. The mean (SD) age of the DLB and MCI-LB groups combined (n = 72) was 69.6 (8.2) years; 66 patients (92%) were men and 6 (8%) were women. At follow-up, 18 participants (49%) with MCI-LB had progressed to probable DLB. Patients with MCI-LB had a faster decline in FDG-SUVr, compared with that of participants without cognitive impairment, in the posterior cingulate, occipital, parietal, temporal, and lateral frontal cortices. The same regions showed greater metabolic decline in patients with DLB than in participants without cognitive impairment, with the addition of anterior-middle cingulate, insula, and medial frontal orbital cortices. Rates of change in FDG-PET in these brain regions were combined into a region of interest (ROI) labeled longitudinal FDG-PET LB meta-ROI. The rate of change in FDG-SUVr in the meta-ROI correlated with the rate of change in CDR-SB, and sample size estimates were reported for potential clinical trials in DLB. Findings were confirmed in the subsample with neuropathologic confirmation (n = 20). Conclusions and Relevance This study found that brain hypometabolism begins to evolve during the prodromal stages of DLB with changes paralleling symptomatic progression. These data may inform clinical practice and trials planning to use FDG-PET for biologic staging, monitoring disease progression, and potentially assessing treatment response.
Patterns in NIA Health Disparities Research Framework Domains and AD‐Plasma Biomarkers
Vassilaki, Maria , Aakre, Jeremiah, Lesnick, Timothy G. , Graff‐Radford, Jonathan, Mosley, Thomas H., Windham, B Gwen, Griswold, Michael E., Lowe, Val J. , Petersen, Ronald C., Aakre, Jeremiah A. , Castillo, Anna , Kremers, Walter K. , Algeciras‐Schimnich, Alicia , Graff‐Radford, Jonathan , Knopman, David S. , Windham, B. Gwen , Jack, Clifford R. , Petersen, Ronald C. , Vemuri, Prashanthi

Alzheimer's & Dementia | January 9, 2025 | Volume: 20 | Issue: S8 | Pages: No page available

10.1002/alz.095372 Get It

AbstractBackgroundThe NIA Health Disparities Research (NIA‐HD) Framework organizes factors in four domains (i.e., environmental, sociocultural, behavioral, and biological), which work together over the lifetime to influence health and health disparities.MethodIn previous work, we employed a 2‐stage approach using factor and principal component (PC) analyses to identify patterns of factors in the domains of the NIA‐HD Framework. We found three PCs that identified related groupings from more than one NIA‐HD domain. PC1: retirement status, residence type, multivitamin use, heart disease, Charlson comorbidity index, walking/balance difficulties, and Beck Depression Inventory (BDI)‐II questions – mainly from the somatic dimension; PC2: physical activity/exercise, social and group activities, education, occupation, cardiometabolic risk factors, and self‐rated health; PC3: national and state area deprivation index ranking and BDI‐II questions – mainly in the cognitive dimension. Age and sex‐adjusted linear regression models were used to assess the cross‐sectional association of each PC with AD‐plasma biomarkers measured using the Quanterix Simoa platform in the Mayo Clinic Study of Aging (MCSA) participants. AD‐plasma biomarkers included Aβ 42/40, phosphorylated‐tau 181 (p‐tau181), plasma glial fibrillary acidic protein (GFAP), and neurofilament light chain (NfL). All analyses were considered statistically significant at a p <0.05.ResultThere were 1300 cognitively unimpaired participants, 50 years old or older, with available plasma biomarkers (mean age (SD) 68.6 (9.5) years; 49.1% were female) at the current study baseline. PC1 and PC3 were associated with higher NfL and p‐tau 181 values (p<0.05). PC1 and PC2 were associated with higher GFAP values (p<0.05). No PCs were associated with the Aβ 42/40 ratio. Findings were mostly similar after additionally adjusting for global cognitive performance and chronic kidney disease.ConclusionWe found that patterns in a wide range of environmental, sociocultural, behavioral, and biological factors were associated with AD plasma biomarkers. Longitudinal studies are warranted to validate findings and support multi‐faceted approaches to address health disparities and achieve disease delay and prevention.
Rethinking the residual approach for estimating cognitive resilience and resistance to AD pathology
Cuppels, Madison, Klinger, Hannah M , Langford, Oliver , Chhatwal, Jasmeer P. , Price, Julie C. , Properzi, Michael J , Amariglio, Rebecca E. , Johnson, Keith A. , Mukherjee, Shubhabrata , Resnick, Susan M. , Tunali, Ilke, Landau, Susan , Lockhart, Samuel N. , Birkenbihl, Colin J. , Boyle, Rory , Coughlan, Gillian , Schultz, Aaron P. , Rentz, Dorene M. , Gottesman, Rebecca F. , Maruff, Paul , Lim, Yen Ying , Masters, Colin L. , Beiser, Alexa , Burnham, Samantha C. , Cohen, Ann D. , Johnson, Sterling C. , Betthauser, Tobey J. , Seshadri, Sudha , Lockhart, Samuel N. , O’Bryant, Sid E. , Vemuri, Prashanthi , Sperling, Reisa Anne , Hohman, Timothy J. , Donohue, Michael , Buckley, Rachel F.

Alzheimer's & Dementia | January 9, 2025 | Volume: 20 | Issue: S8 | Pages: No page available

10.1002/alz.094824 Get It

AbstractBackgroundThe residual approach has found wide application in researching cognitive resilience, a phenomenon conceptually understood as cognitive performance being better‐than‐typical for an individual, despite apparent AD pathology. The standard residual approach extracts information about an individual’s resilience from the residuals of a linear model predicting cognition. This approach is subject to several limiting assumptions. Here, we explore the implications of these assumptions and propose an alternative predictive modeling approach which circumvents them.MethodsOur alternative approach relies on training a machine learning model on a sample of participants who follow a “typical” clinical progression (Fig. 1A). Residuals are then extracted for a heterogeneous dataset that potentially includes resilient participants by comparing observed cognitive outcomes to those predicted by the “typical” model (Fig. 1B). Additionally, our estimate can be refined by effectively estimating and removing model error from the extracted residual by leveraging a second predictive model (Fig. 1C). Using simulated data, we explore the assumptions made by the standard approach and the consequences of their violation. We then contrast this against our approach.ResultsOur simulations demonstrated that the standard residual approach only extracted accurate resilience estimates if the predictors used in the model explained cognition sufficiently well, while being unrelated to resilience itself. That is, as the predictors explain more of the resilience, the residuals became increasingly determined by model error (Fig. 2). We found that residuals achieved with our approach are more precise and provide individualized estimates that are unaffected by the aforementioned trade‐off (Fig. 3).ConclusionsOur approach holds several advantages over the standard approach: The definition of resilience can be freely adjusted and enforced via different definitions of “typical”, it allows for incorporating complex, non‐linear models without removing relevant information from the residual, the error component of the residual can be estimated through cross‐validation, and all predictors that potentially explain cognition can be included into the model without losing resilience information from the residual. Our approach can be used to measure any phenomenon that can be operationalized as a deviation from a typical outcome and, thus, is also applicable for researching resistance to pathology.
SomaScan plasma proteomics of cSVD
Chen, Jingsha, Yang, Yunju , Fornage, Myriam, Peng, Zhongsheng , Daya, Gulzar N. , Longstreth, W.T., Kalani, Rizwan , Sharma, Malveeka , Psaty, Bruce M., Mosley, Thomas H., Hughes, Timothy M. , Gómez, Gabriela , Shi, Liu , Fohner, Alison E. , Fornage, Myriam , Duggan, Michael R. , Tin, Adrienne , Schlosser, Pascal , Psaty, Bruce M , Nevado‐Holgado, Alejo J. , Buckley, Noel J. , Gottesman, Rebecca F. , Lutsey, Pamela L. , Jack, Clifford R. , Sullivan, Kevin , Mosley, Thomas H. , Coresh, Josef , Walker, Keenan A.

Alzheimer's & Dementia | January 9, 2025 | Volume: 20 | Issue: S2 | Pages: No page available

10.1002/alz.084576 Get It

AbstractBackgroundCerebral small vessel disease (cSVD), as defined by neuroimaging characteristics such as white matter hyperintensities (WMHs), cerebral microhemorrhages (CMHs), and lacunar infarcts, is highly prevalent and has been associated with dementia risk and other clinical sequelae. Although risk factors for cSVD have been identified, little is known about the biological processes and molecular mediators that influence cSVD development and progression.MethodsWithin the Atherosclerosis Risk in Communities (ARIC) study, we used SomaScan Multiplexed Proteomic technology to relate 4,877 plasma proteins to concurrently measured MRI‐defined cSVD characteristics, including WMHs, CMHs, and lacunar infarcts, in late‐life (n=1508; mean age: 76). Candidate protein associations with WMH volume were replicated in the Cardiovascular Health Study (n=765; mean age: 73) and Baltimore Longitudinal Study of Aging (n=902; mean age: 66). Cohort‐specific effect estimates were pooled using a fixed‐effect, inverse variance weighted meta‐analysis. Within 4228 non‐demented older adults in ARIC, we examined the association of WMH‐associated proteins with eight‐year dementia risk (641 incident dementia cases) using multivariate Cox proportional hazard models. All multivariate regression models were adjusted for demographic, kidney function, and cardiovascular risk variables.ResultsThis proteome‐wide analysis of older adults identified 13 WMH‐associated plasma proteins involved in synaptic function, endothelial integrity, and angiogenesis (Figures 1a, 2a). Nine of these proteins replicated in one or more external cohort (Figures 1b, 2b) and two proteins, oligodendrocyte myelin glycoprotein (OMG) and neuronal pentraxin receptor (NPTXR), remained associated with late‐life WMH volume when measured nearly two decades earlier during midlife (Figures 1c, 2c). Eight of the 13 WMH‐associated proteins were associated with lacunar infarcts, 6 with subcortical CMHs, and 4 with lobar CMHs (Figures 1d, 2d). Although none of the genes coding for WMH‐associated proteins have been nominated by WMH GWAS, 7 of these genes have been previously linked to cardiometabolic traits known to influence cSVD, such as blood pressure and cholesterol (Figures 1e, 2e). Finally, 11 candidate proteins were associated with incident dementia, underscoring their clinical relevance (Figures 1f, 2f).ConclusionsThis large‐scale proteomic analysis within longitudinal community‐based samples identified several plasma proteins, including OMG and NPTXR, as top candidate biomarkers for elevated WMH volume and its clinical manifestations.
Substantia nigra iron deposition in Lewy body disease: an MRI quantitative susceptibility mapping and neuropathology study
Przybelski, Scott A. , Lesnick, Timothy G. , Reichard, Ross R., Ono, Daisuke , Gunter, Jeffrey L. , Lowe, Val J. , Forsberg, Leah K. , Fields, Julie A. , Savica, Rodolfo , Graff‐Radford, Jonathan , Graff‐Radford, Neill R. , Petersen, Ronald C. , Diaz‐Galvan, Patricia , Nguyen, Aivi T. , Murray, Melissa E. , Dickson, Dennis W. , Schwarz, Christopher G. , Senjem, Matthew L. , Ramanan, Vijay K. , Jones, David T. , Botha, Hugo , Louis, Erik K. St. , Knopman, David S. , Day, Gregory S. , Jack, Clifford R. , Ferman, Tanis J. , Boeve, Bradley F. , Kantarci, Kejal

Alzheimer's & Dementia | January 9, 2025 | Volume: 20 | Issue: S2 | Pages: No page available

10.1002/alz.091491 Get It

AbstractBackgroundParkinson’s disease and dementia with Lewy bodies are characterized by abnormal iron deposition in the substantia nigra, which can be measured with quantitative susceptibility mapping (QSM) on MRI. However, neuropathologic validation of the increased QSM in the substantia nigra associated with Lewy body disease (LBD) is lacking. We compared substantia nigra QSM on antemortem MRI between patients with and without Lewy‐related pathology which was confirmed by autopsy in all cases.MethodWe studied cases with antemortem QSM who underwent autopsy from the Mayo Clinic Alzheimer’s Disease Research Center and Mayo Clinic Study of Aging (n=54). Immunohistochemistry was performed with rabbit NACP antibody against the amino acids 98‐115 of the α‐synuclein protein to detect Lewy‐related pathology. After neuropathologic evaluation, cases were classified as LBD‐present (n=13) if they had Lewy‐related pathology and LBD‐absent (n=42) if they did not have Lewy‐related pathology. Alzheimer’s disease co‐pathology was present in 9 of the LBD‐present cohort (70%). QSM was calculated for the whole substantia nigra and the two sub‐regions: pars compacta and pars reticulata. Non‐parametric Wilcoxon rank‐sum test was used to compare substantia nigra QSM values between LBD‐present and LBD‐absent cases. Area under the curve (AUC) analyses tested the accuracy of QSM to distinguish the two groups.ResultsLBD‐present group had higher QSM values in the substantia nigra than LBD‐absent group. Furthermore, sub‐regional analyses showed that the LBD‐present group had higher QSM in the substantia nigra pars compacta (p=0.008) but not in the pars reticulata than the LBD‐absent group (Figure 1). QSM of the substantia nigra pars compacta distinguished LBD‐present and LBD‐absent cases with good accuracy (AUC=0.74; p=0.006; Figure 2).ConclusionThis study provides neuropathologic insight into the relevance of QSM of substantia nigra pars compacta as an in‐vivo biomarker of autopsy‐confirmed LBD. These findings indicate that imaging evidence of abnormal iron deposition in the substantia nigra may serve as a biomarker of Lewy‐related pathology in patients with primary LBD (i.e., Parkinson disease, dementia with Lewy bodies) and patients with potential LBD co‐pathology (e.g., patients with Alzheimer disease).
Increase in white matter hyperintensities in long‐COVID depends on age and hospitalization during acute SARS‐CoV‐2
Atık, Merve, Kendall‐Thomas, June, Przybelski, Scott A. , Kantarci, Orhun H. , Toledano, Michel , Fought, Angela J. , Lesnick, Timothy G. , Gundry, Katie, Lorente, Alfredo, Thotland, Jeromy, Li, Xiufeng , Manousakis, Georgios , Metzler, Abby, Byrne, Keenan, Juttukonda, Meher R. , Salat, David H. , Sherman, Janet C. , Pollak, Lauren, Nabi, Mehreen, Rehman, Sana , Karmonik, Christof , Gillani, Syed A , Flores, Vanesa, Davis, Rachel, Ashizawa, Tetsuo , Ratai, Eva, Kantarci, Kejal, Harrold, G. Kyle , Zeydan, Burcu , Senjem, Matthew L. , Schwarz, Christopher G. , Silva, Ana Isabel , Joers, James M. , Lorente, Alfredo, Deelchand, Dinesh K. , Park, Young Woo , Lenglet, Christophe , Eberly, Lynn E. , Mukerji, Shibani S. , Yaşar, Sevil , Öz, Gülin , Kantarci, Kejal

Alzheimer's & Dementia | January 9, 2025 | Volume: 20 | Issue: S2 | Pages: No page available

10.1002/alz.090998 Get It

AbstractBackgroundApproximately 10% of patients with acute SARS‐CoV‐2 infection present with persistent symptoms recognized as the long‐COVID. Neurological and cognitive symptoms are prevalent in long‐COVID, requiring a deeper understanding of the biological basis of this condition for potential therapeutic interventions. Cerebrovascular complications are observed during acute infection, underscoring the importance of understanding cerebrovascular outcomes. Our objective was to investigate white matter hyperintensities (WMH) as a potential indicator of microvascular disease associated with long‐COVID in the brainMethodParticipants with long‐COVID (n=71; hospitalized, n=9, non‐hospitalized, n=62 during the acute infection) and controls (n=50) who did not have a reported infection were recruited from the community at five US sites that participated in the COVID‐Brain‐Advanced‐Imaging‐Network (COVID‐BRAIN) project. To be included, participants with long‐COVID had to experience neurological or cognitive sequelae within 6 months after a confirmed infection and continued to show at least one neurological symptom. Clinical evaluation and MRI were performed an average of 20±10 months after the acute infection. WMH volumes were measured from the 3D T2‐weighted FLAIR MRIs using a semi‐automated approach for the WMH segmentation. A linear regression model predicting log transformed WMH volume was used to investigate the association of age, groups (hospitalized long‐COVID, non‐hospitalized long‐COVID, controls), and the interaction of these two predictors along with an adjustment for total intracranial volume. Additionally, predicted regression lines have been plotted on the untransformed WMH scale.ResultWe observed a greater age‐dependent increase in WMH volumes in the hospitalized patients with long‐COVID compared to the control group (group*age interaction, p=0.005). We did not observe this difference in slopes in the non‐hospitalized patients with long‐COVID compared to the controls. Figure shows the slopes of WMH volume as a percentage of the total intracranial volume by age in the three groups.ConclusionOur preliminary observation in this ongoing long‐Covid study suggests that hospitalization during acute COVID is associated with the age‐dependent increase in microvascular injury in the white matter. Older adults with acute infection that require hospitalization are more susceptible to cerebrovascular adverse outcomes than controls or those who do not require hospitalization. Impact of such microvascular changes on cognitive outcomes and persistence of post‐COVID symptoms is yet to be studied.