Citations

Abstract Alzheimer's disease (AD) clinical trials are designed and powered to detect the impact of a therapeutic intervention, and there has been considerable discussion on what constitutes a clinically meaningful change in those receiving treatment versus placebo. The pathology of AD is complex, beginning many years before clinical symptoms are detectable, with multiple potential opportunities for therapeutic engagement. Introducing treatment strategies early in the disease and assessing meaningful change over the course of an 18‐month clinical trial are critical to understanding the value to an effective intervention. With new clinical trial data expected soon on emerging therapeutics from several AD studies, the Alzheimer's Association convened a work group of experts to discuss key considerations for interpreting data from cognitive and functional measures and what is considered a clinically meaningful benefit or meaningful slowing of this fatal disease. Our expectations of outcomes from therapeutic interventions in AD may need to be modified.

Study Design. Delphi method. Objective. To gain consensus on the following questions: (1) When should anticoagulation/antiplatelet (AC/AP) medication be stopped before elective spine surgery?; (2) When should AC/AP medication be restarted after elective spine surgery?; (3) When, how, and in whom should venous thromboembolism (VTE) chemoprophylaxis be started after elective spinal surgery? Summary of Background Data. VTE can lead to significant morbidity after adult spine surgery, yet postoperative VTE prophylaxis practices vary considerably. The management of preoperative AC/AP medication is similarly heterogeneous. Materials and Methods. Delphi method of consensus development consisting of three rounds (January 26, 2021, to June 21, 2021). Results. Twenty-one spine surgeons were invited, and 20 surgeons completed all rounds of questioning. Consensus (>70% agreement) was achieved in 26/27 items. Group consensus stated that preoperative Direct Oral Anticoagulants should be stopped two days before surgery, warfarin stopped five days before surgery, and all remaining AC/AP medication and aspirin should be stopped seven days before surgery. For restarting AC/AP medication postoperatively, consensus was achieved for low-risk/medium-risk/high-risk patients in 5/5 risk factors (VTE history/cardiac/ambulation status/anterior approach/operation). The low/medium/high thresholds were POD7/POD5/POD2, respectively. For VTE chemoprophylaxis, consensus was achieved for low-risk/medium-risk/high-risk patients in 12/13 risk factors (age/BMI/VTE history/cardiac/cancer/hormone therapy/operation/anterior approach/staged separate days/staged same days/operative time/transfusion). The one area that did not gain consensus was same-day staged surgery. The low-threshold/medium-threshold/high-threshold ranges were postoperative day 5 (POD5) or none/POD3-4/POD1-2, respectively. Additional VTE chemoprophylaxis considerations that gained consensus were POD1 defined as the morning after surgery regardless of operating finishing time, enoxaparin as the medication of choice, and standardized, rather than weight-based, dose given once per day. Conclusions. In the first known Delphi study to address anticoagulation/antiplatelet recommendations for elective spine surgery (preoperatively and postoperatively); our Delphi consensus recommendations from 20 spine surgeons achieved consensus on 26/27 items. These results will potentially help standardize the management of preoperative AC/AP medication and VTE chemoprophylaxis after adult elective spine surgery.

Introduction: EXCELLENT (NCT03685578) is a global prospective, multicenter, real-world registry of mechanical thrombectomy for stroke with the EmboTrap device as first line treatment which includes clot collection and analysis. Aim of the study: To report the rates of clinical outcomes and clot characteristics associated with first pass reperfusion in EXCELLENT. Methods: Per pass angiographic outcomes assessed by an independent core lab were available in 984 subjects Analysis of clot from 538 cases was performed by independent central labs blinded to clinical data. 90-day mRS assessment was blinded to subject data. Results: First pass reperfusion of mTICI 2b-3 (63.2%) and 2c-3 (38.3%) was significantly predictive of mRS 0-2 or ≤pre-stroke (p=0.011 and p=0.016) but not all-cause mortality at 90 days (p=0.080 and p=0.123, respectively). Further, mTICI 2c-3 in one pass was associated with a higher rate of mRS 0-2 or ≤pre-stroke vs. mTICI 2c-3 reperfusion in >1 pass, (55.5% and 45.1%, respectively, p=0.013) and a rate of all-cause mortality at 90 days of 14.6% vs. 19.8% (p=0.097). Full patient characteristics and clinical outcomes are shown in Table 1. Notable clot composition findings included: RBC (%, mean±SD): mTICI 2c-3, 1 pass 47.69±22.25, mTICI 2c-3, >1 pass 43.86±19.05, (p=0.088); fibrin: mTICI 2c-3, 1 pass 23.20±13.80, mTICI 2c-3 >1 pass 25.40 ± 13.52 (p=0.131); von Willebrand factor (VWF): mTICI2c-3, 1 pass 16.09±14.62, mTICI 2c-3, >1 pass 19.42±17.15 (p=0.038). Conclusions: First pass reperfusion in the EXCELLENT registry was associated with better clinical outcomes at 90 days. Clots retrieved with first pass reperfusion had higher RBC and lower fibrin and VWF content compared to those who achieved reperfusion at greater than one pass.

AbstractAlterations of cerebral glucose metabolism can be detected in patients with isolated rapid eye movement sleep behaviour disorder, a prodromal feature of neurodegenerative diseases with α-synuclein pathology. However, metabolic characteristics that determine clinical progression in isolated rapid eye movement sleep behaviour disorder and their association with other biomarkers need to be elucidated. We investigated the pattern of cerebral glucose metabolism on 18F-fluorodeoxyglucose PET in patients with isolated rapid eye movement sleep behaviour disorder, differentiating between those who clinically progressed and those who remained stable over time. Second, we studied the association between 18F-fluorodeoxyglucose PET and lower dopamine transporter availability in the putamen, another hallmark of synucleinopathies. Patients with isolated rapid eye movement sleep behaviour disorder from the Mayo Clinic Alzheimer’s Disease Research Center and Center for Sleep Medicine (n = 22) and age-and sex-matched clinically unimpaired controls (clinically unimpaired; n = 44) from the Mayo Clinic Study of Aging were included. All participants underwent 18F-fluorodeoxyglucose PET and dopamine transporter imaging with iodine 123-radiolabeled 2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl) nortropane on single-photon emission computerized tomography. A subset of patients with isolated rapid eye movement sleep behaviour disorder with follow-up evaluations (n = 17) was classified as isolated rapid eye movement sleep behaviour disorder progressors (n = 7) if they developed mild cognitive impairment or Parkinson’s disease; or isolated rapid eye movement sleep behaviour disorder stables (n = 10) if they remained with a diagnosis of isolated rapid eye movement sleep behaviour disorder with no cognitive impairment. Glucose metabolic abnormalities in isolated rapid eye movement sleep behaviour disorder were determined by comparing atlas-based regional 18F-fluorodeoxyglucose PET uptake between isolated rapid eye movement sleep behaviour disorder and clinically unimpaired. Associations between 18F-fluorodeoxyglucose PET and dopamine transporter availability in the putamen were analyzed with Pearson’s correlation within the nigrostriatal pathway structures and with voxel-based analysis in the cortex. Patients with isolated rapid eye movement sleep behaviour disorder had lower glucose metabolism in the substantia nigra, retrosplenial cortex, angular cortex, and thalamus, and higher metabolism in the amygdala and entorhinal cortex compared with clinically unimpaired. Patients with isolated rapid eye movement sleep behaviour disorder who clinically progressed over time were characterized by higher glucose metabolism in the amygdala and entorhinal cortex, and lower glucose metabolism in the cerebellum compared with clinically unimpaired. Lower dopamine transporter availability in the putamen was associated with higher glucose metabolism in the pallidum within the nigrostriatal pathway; and with higher 18F-fluorodeoxyglucose uptake in the amygdala, insula, and temporal pole on a voxel-based analysis, although these associations did not survive after correcting for multiple comparisons. Our findings suggest that cerebral glucose metabolism in isolated rapid eye movement sleep behaviour disorder is characterized by hypometabolism in regions frequently affected during the prodromal stage of synucleinopathies, potentially reflecting synaptic dysfunction. Hypermetabolism is also seen in isolated rapid eye movement sleep behaviour disorder, suggesting that synaptic metabolic disruptions may be leading to a lack of inhibition, compensatory mechanisms, or microglial activation, especially in regions associated with nigrostriatal degeneration.

Abstract Dysexecutive Alzheimer’s disease (dAD) manifests as a progressive dysexecutive syndrome without prominent behavioral features, and previous studies suggest clinico-radiological heterogeneity within this syndrome. We uncovered this heterogeneity using unsupervised machine learning in 52 dAD patients with multimodal imaging and cognitive data. A spectral decomposition of covariance between FDG-PET images yielded six latent factors (“eigenbrains”) accounting for 48% of variance in patterns of hypometabolism. These eigenbrains differentially related to age at onset, clinical severity, and cognitive performance. A hierarchical clustering on the eigenvalues of these eigenbrains yielded four dAD subtypes, i.e. “left-dominant,” “right-dominant,” “bi-parietal-dominant,” and “heteromodal-diffuse.” Patterns of FDG-PET hypometabolism overlapped with those of tau-PET distribution and MRI neurodegeneration for each subtype, whereas patterns of amyloid deposition were similar across subtypes. Subtypes differed in age at onset and clinical severity where the heteromodal-diffuse exhibited a worse clinical picture, and the bi-parietal had a milder clinical presentation. We propose a conceptual framework of executive components based on the clinico-radiological associations observed in dAD. We demonstrate that patients with dAD, despite sharing core clinical features, are diagnosed with variability in their clinical and neuroimaging profiles. Our findings support the use of data-driven approaches to delineate brain–behavior relationships relevant to clinical practice and disease physiology.

Disease-modifying therapies in both light chain and transthyretin amyloidosis have improved patient functional status and survival. Conceivably, as heart failure may progress despite amyloid therapies, more patients may be considered for heart transplantation. In earlier eras, extra-cardiac amyloid deposits significantly reduced post-heart transplant patient survival and functional status compared to the non-amyloid population. In the modern era, transplant centres have reported improved outcomes in amyloidosis as patient selection has grown more stringent. Importantly, systematic candidate evaluation should assess the degree of extra-cardiac involvement, the effectiveness of disease-modifying therapies and downstream effects on patients’ nutrition and frailty. This review outlines such an overall approach while also considering that organ-specific selection criteria may vary between individual transplant centres. A methodical approach to patient evaluation will promote better understanding of the prevalence and severity of extra-cardiac disease in amyloidosis patients referred for heart transplantation and of any disparities in decision outcomes in this population.

Background: Phosphorylated cytoplasmic tau inclusions correlate with and precede cognitive deficits in Alzheimer’s disease (AD). However, pathological tau accumulation and relationships to synaptic changes remain unclear. Objective: To address this, we examined postmortem brain from 50 individuals with the full spectrum of AD (clinically and neuropathologically). Total tau, pTau231, and AMPA GluR1 were compared across two brain regions (entorhinal and middle frontal cortices), as well as clinically stratified groups (control, amnestic mild cognitive impairment, AD dementia), NIA-AA Alzheimer’s Disease Neuropathologic Change designations (Not, Low, Intermediate, High), and Braak tangle stages (1–6). Significant co-existing pathology was excluded to isolate changes attributed to pathologic AD. Methods: Synaptosomal fractionation and staining were performed to measure changes in total Tau, pTau231, and AMPA GluR1. Total Tau and pTau231 were quantified in synaptosomal fractions using Quanterix Simoa HD-X. Results: Increasing pTau231 in frontal postsynaptic fractions correlated positively with increasing clinical and neuropathological AD severity. Frontal cortex is representative of early AD, as it does not become involved by tau tangles until late in AD. Entorhinal total tau was significantly higher in the amnestic mild cognitive impairment group when compared to AD, but only after accounting for AD associated synaptic changes. Alterations in AMPA GluR1 observed in the entorhinal cortex, but not middle frontal cortex, suggest that pTau231 mislocalization and aggregation in postsynaptic structures may impair glutamatergic signaling by promoting AMPA receptor dephosphorylation and internalization. Conclusion: Results highlight the potential effectiveness of early pharmacological interventions targeting pTau231 accumulation at the postsynaptic density.

Abstract Background Computed tomography enterography (CTE) is frequently used to assess stricturing Crohn’s disease (CD). However, the reliability of CTE items used for assessment has not been established and there is no validated radiologic stricture severity index. Methods We conducted a retrospective study of 43 patients with symptomatic, terminal ileal stricturing CD. Four radiologists assessed a comprehensive list of pre-defined radiologic items potentially associated with stricture severity in 48 CTE scans in two separate rounds in random order. Reliability was quantified using the intraclass correlation coefficient (ICC). Items with at least moderate (ICC≥0.41) inter-rater reliability that were correlated with a visual analogue scale of overall stricture severity were candidate items for the development of a CTE stricture index. Results Inter-rater reliability was almost perfect for assessment of luminal diameter of pre-stenotic dilation (ICC 0.817 [95% confidence interval 0.703, 0.878]), substantial for stricture length (ICC 0.628 [0.419, 0.797]), and moderate for stricture wall thickness (0.482 [0.330, 0.601]). Intra-rater reliability was almost perfect (ICC ≥ 0.850) for all three items. A stricture severity index was derived and was well calibrated (optimism-adjusted calibration slope = 1.009), with scores calculated as the sum of stricture length (cm) + luminal diameter of pre-stenotic dilation (mm) + 5 x stricture wall thickness (mm). Conclusion Stricture length, prestenotic dilation, and stricture wall thickness can be reliably assessed, and are component items for a novel CTE stricture index (CTE-SI) of stricture severity for CD-related terminal ileal strictures. Additional external index validation for clinical and research contexts is required.

Purpose: Foveal herniation occurs when neuroretinal tissue protrudes through and above the level of an epiretinal membrane. This study describes the visual symptoms and spectral domain optical coherence tomography findings associated with foveal herniation and evaluates the postoperative visual, anatomical, and surgical outcomes. Methods: A multicenter retrospective review of patients diagnosed with epiretinal membrane identified 59 patients with preoperative foveal herniation on spectral domain optical coherence tomography. Data regarding visual symptoms, preoperative and postoperative best-corrected visual acuity (BCVA), central retinal thickness, macular volume, and size of foveal herniation were collected, and statistical analysis was performed. Results: A total of 58 of the 59 patients with foveal herniation underwent surgical epiretinal membrane peeling, with foveal contour restored in 53.5% of patients after surgery. Average BCVA improved from 20/80 to 20/40 Snellen equivalent at most-recent postoperative visit ( P < 0.0001). The average central retinal thickness decreased from 632 µ m to 432 µ m ( P < 0.0001) and the average macular volume decreased from 11.3 mm 3 to 9.5 mm 3 ( P < 0.0001) at 3 months postoperatively. Preoperatively, greater herniation height was associated with worse BCVA ( P = 0.008), greater central retinal thickness ( P = 0.01), retinoschisis, cystoid macular edema, foveolar detachment, ellipsoid zone abnormality, and external limiting membrane abnormalities ( P < 0.05). Postoperatively, there was a decrease in retinoschisis, cystoid macular edema, foveolar detachment, ellipsoid zone, and external limiting membrane abnormality ( P < 0.05) on spectral domain optical coherence tomography. Conclusion: Patients with larger foveal herniation height had greater preoperative central retinal thickness, worse preoperative and postoperative BCVA, and more intraretinal abnormalities on spectral domain optical coherence tomography. Surgical epiretinal membrane peeling in patients with foveal herniation resulted in a significant improvement in patients' BCVA and microstructural abnormalities.