Introduction: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited cerebral small vessel disease, yet there is currently no biomarker for early detection. This study aims to identify retinal biomarkers of NOTCH3 carriers using optical coherence tomography (OCT) from the UK Biobank. Methods: We conducted a cross-sectional, matched case-control study of individuals with or without CADASIL from the UK Biobank between 2006 and 2010. All participants had retinal OCT scan and cognitive assessment. Cases were identified based on pathogenic NOTCH3 mutations and 1:1 matched with healthy controls based on age, sex, hypertension, diabetes mellitus, and smoking status. Baseline characteristics and cognitive test scores were compared using chi-square or Mann-Whitney-U test appropriately. Macular thickness (central, inner, and outer subfields) (Figure) and retinal nerve fiber layer (RNFL) thickness were compared using Wilcoxon signed-rank test. Results: Our analysis included 134 participants (67 CADASIL cases, 67 controls) with a mean age of 54±8 years. There were no differences in visual acuity between the two groups. CADASIL performed worse in prospective memory (0.043), verbal and numerical reasoning (p=0.178), visual memory (p=0.227), and processing speed (p=0.101) than matched controls. Participants with CADASIL had significantly thinner macular inner subfield at the superior (p=0.006), temporal (p=0.008), and nasal (p=0.034) quadrants, and significantly thinner RNFL (p=0.008) compared to controls (Table). Conclusion: Individuals with CADASIL have reduced thickness in the inner macular subfield and RFNL relative to matched controls. These retinal group differences were not associated with differences in visual acuity and may reflect early pericyte dysfunction and microvascular ischemia. Longitudinal studies are needed to assess the temporal relationship between these retinal changes and disease progression.
Abstract WMP18: The Association between Cerebral Microbleed Patterns and Incident Dementia: The ARIC-Neurocognitive Study
Background: Cerebral microbleeds (CMBs) are associated with incident dementia, but the impact of specific CMB patterns is unclear. CMBs in lobar regions suggest cerebral amyloid angiopathy (CAA), which is sometimes accompanied by superficial siderosis (SS), while subcortical CMBs indicate hypertensive origins. This study investigates the association between CMB patterns and dementia risk in the community-based longitudinal Atherosclerosis Risk in Communities Neurocognitive Study (ARIC-NCS). Methods: All ARIC-NCS participants with a 3T research MRI at visit 5 (2011-13; aged 67-90) without intracerebral hemorrhage or dementia were included. CMB and SS presence and location were coded from T2* GRE sequences. Individuals were classified into one of four patterns: no CMBs, only subcortical, mixed (lobar and/or SS + subcortical), and only lobar and/or SS. Incident dementia diagnoses were defined by cognitive testing (in-person and telephone), informant interviews, and hospital discharge codes or death certificates. Cox proportional-hazards models assessed the association between the presence, patterns, and frequency of CMBs (0,1,2,3+), presence of SS, and incident dementia from visit 5 through 2020. Model covariates included demographics, vascular risk factors, and imaging markers of small vessel disease. Results: Among 1609 participants, 364 had CMBs (Table 1). Participants with CMBs tended to be older and female compared to those without CMBs. Compared to individuals with no CMBs, presence of any CMBs was associated with an increased risk of dementia (Table 2). Compared to individuals without CMBs, individuals with only lobar CMBs and/or SS had an increased risk of incident dementia, as did individuals with mixed CMBs, but individuals with subcortical-only did not. Participants with ≥3 CMBs of any variant had an increased risk of incident dementia vs no CMBs. Although SS was infrequent, its presence (vs no SS) was associated with an elevated risk of dementia. Conclusion: CMBs, particularly in a mixed or lobar and/or SS-only pattern, are linked to an increased risk of incident dementia. The number of recurrent CMBs and any SS also showed an increased dementia risk. These data support that dementia risk is high in individuals with a CAA-type CMB pattern, but also emphasize that a mixed pattern, not typical of CAA alone, is associated with a high risk of dementia. Further studies should evaluate mechanisms by which these different patterns contribute to dementia.
Abstract WP292: Efficacy of Lipid-Lowering Therapies in Reducing Stroke Risk in Intracranial Atherosclerosis: A Systematic Review and Meta-Analysis
Background: Intracranial atherosclerosis (ICAS) is a common stroke cause, with a recurrent stroke risk of up to 18% per year despite treatment advances. Although lipid-lowering therapies reduce cardiovascular events, their effect on stroke risk in ICAS remains unclear. Objective: To perform a systematic review and meta-analysis assessing the efficacy of lipid-lowering therapies in improving stroke outcomes among patients with ICAS. Methods: A systematic search of PubMed, Embase, Web of Science, Cochrane, and other databases was conducted from inception to November 2023. Eligible studies compared lipid-lowering therapies (Statins and PCSK9i) to standard care or placebo in patients with ICAS. The primary outcome was the incidence of stroke. Pooled relative risks (RR) with 95% confidence intervals (CI) were calculated using a random-effects model, and forest plots were constructed. Chi-square and I 2 statistics were used to assess heterogeneity. Results: Seven observational studies and two randomized controlled trials involving 1,902 ICAS patients were included. Of these, 801 received lipid-lowering therapy, and 1,101 received standard care or placebo. The weighted mean follow-up was 17.6 months (IQR 9.75-25.5). The weighted mean age was 63.7 years (range 55-68) for the lipid-lowering group and 64.0 years (range 50-66) for controls. Females comprised 42% of both groups. Hypertension was present in 74% of the intervention group and 71% of controls. A history of stroke was reported in 32% of the intervention group and 29% of controls. The weighted mean baseline LDL level was 105 mg/dL in the intervention group and 107 mg/dL in controls. The weighted mean change in LDL pre- and post-treatment in the intervention group was -47.18 mg/dL, compared to -12.39 mg/dL in controls. The incidence of ischemic stroke was 5.0% (40/801) in the lipid-lowering group versus 13.0% (143/1,101) in controls (RR 0.40; 95% CI 0.24-0.64; P<0.001, Figure 1a). Subgroup analysis of studies comparing statin versus no statin treatment showed an RR of 0.40 (95% CI 0.30-0.92; P<0.05, Figure 1b). Another subgroup analysis comparing PCSK9 inhibitors and statins versus statins only found an RR of 0.44; 95% CI 0.20-0.96; P<0.05, Figure 1c). Conclusions: Lipid-lowering therapies significantly reduce the risk of ischemic stroke in patients with intracranial atherosclerosis. The addition of PCSK9 inhibitors to statins appears to provide added stroke risk reduction.
Abstract TP215: Impact of Carotid Stenosis on Cerebral Glucose Metabolism
Background: Carotid stenosis has been associated with stroke and cognitive impairment. It remains unclear if hypometablism, a marker for neurodegeneration, may be in the mechanistic pathway in the association between carotid stenosis and cognitive decline. This study aims to investigate whether patients with carotid stenosis exhibit reduced cerebral glucose metabolism, using 18-FDG PET imaging as a sensitive measure of brain’s glucose metabolism. Methods: We have identified 138 patients from one health care system who underwent 18-FDG PET imaging and had extracranial carotid imaging (doppler ultrasound/CT angiography/MR angiography) within 1 year of PET scan. Severity of carotid stenosis was defined using NASCET criteria as <50% (mild), 50-69% (moderate), >70% (high-grade). Cerebral glucose metabolism was quantified by measuring standardized uptake value ratio (SUVR) after normalizing to pons in 12 different regions of interest (ROI). Hypometabolism was defined using the cutoff of SUVR <1.41. SUVR and hypometabolism measures were compared across severity of carotid stenosis. Results: Of 138 patients identified, 54 were excluded due to indeterminant ipsilateral hemisphere status. Mild, moderate and severe stenosis was present in 86.9%, 4.8%, 8.3%, respectively. The analysis revealed a numerically reduced cerebral glucose metabolism in patients with moderate to severe carotid stenosis compared to control subjects (Table 1). The most pronounced decrease in FDG uptake was observed in regions supplied by the affected carotid artery, particularly the ipsilateral cortical areas. There was a numerically increased risk of hypometabolism with increasing carotid stenosis: Adjusted odds of hypometabolism ipsilateral to the carotid stenosis were 2.90, 5.56 across patients with moderate and high-grade carotid stenosis in sensorimotor cortex (trend-P=0.095). These findings were consistent across different regions supplied by the stenotic carotid artery but attenuated in territories supplied by unaffected posterior arteries (Table 2). Conclusions: FDG-PET imaging demonstrates reduced glucose metabolism in patients with carotid stenosis, suggesting that cerebral hypoperfusion may contribute to the metabolic disturbances observed in these patients. These results underscore the importance of early detection and management of carotid stenosis to mitigate potential cerebral metabolic deficits and the associated risk of dementia and ischemic stroke.
P-709. Risk factors for hypoxia and mechanical ventilation in Respiratory Syncytial Virus (RSV) infections in hospitalized solid organ transplant recipients (SOTR)
Abstract Background RSV is a common respiratory infection that causes significant morbidity in SOTR. However, risk factors for complications such as hypoxic respiratory failure, mechanical ventilation, and secondary infections have not been well described. Methods This retrospective, international, multicenter cohort study is actively recruiting SOTR hospitalized with RSV. Here, we analyzed data from Mayo Clinic (Rochester, Florida, Arizona), Miami Transplant Institute, Cleveland Clinic, and Royal Melbourne Hospital between 2016 and 2019. Secondary infection was defined as culture positive infection within 90 days of RSV diagnosis. Whenever appropriate, logistic and Cox regression analysis were conducted to identify risk factors. Survival functions were estimated using the Kaplan-Meier method.Figure 1:Forest plots of multivariable logistic regression models for risk factors for A) hypoxia, B) secondary infections, C) mechanical ventilation. Note: all variables included are the ones statistically significant on univariate analysis. Abbreviations: CI, confidence interval; OR, Odds ratio; LRTI: lower respiratory tract infection. Results 233 SOTRs (58.8% male; median, 61 years), including 77 (49.1%) kidney, 23 (9.9%) liver, 79 (33.9%) lung, and 38 (16.3%) heart transplants (Table). Hypoxic respiratory failure, mechanical ventilation, and secondary infection were seen in 98 (42.1%), 23 (9.9%), and 58 (24.9%) patients, respectively. After multivariate analysis, age >60 years, symptoms and imaging evidence of lower respiratory tract infection (LRTI) were associated with oxygen requirement (Figure 1A); similar results were observed in an analysis of the lung transplant cohort only. Risk factors on multivariate analysis for secondary infection include a history of rejection within six months and mechanical ventilation (Figure 1B). Risk factors for mechanical ventilation included age >60 years and LRTI on imaging (Figure 1C) after multivariate analysis. Seventeen (7.3%) patients died within 90 days of diagnosis. Cox univariate analysis identified age >60 years and LRTI on imaging, secondary infections, mechanical ventilation and hypoxia on admission were associated with higher mortality (Figure 2 and 3).Figure 2:Forest plot with Cox proportional hazards models. Note: only univariate results shown, multivariate not done due to low number of events. Conclusion This multicenter study of SOTR hospitalized with RSV identified older age ( >60 years old) as a risk factor for hypoxic respiratory failure, mechanical ventilation and death. Mechanical ventilation and a history if rejection within six months of RSV were associated with increased risk of secondary infections, identifying them as high-risk that needs close surveillance for this complication.Figure 3:Effects of A) Age older than 60 years old and B) mechanical ventilation on 90 day probability of survival after RSV infection Disclosures Michelle Yong, MBBS, FRACP, MPH, PhD, MSD: Grant/Research Support|MSD: Honoraria|Takeda: Advisor/Consultant Yoichiro Natori, MD, Eurofin/Viracor: Honoraria|Nobel Pharma: Advisor/Consultant
P-1650. Clinical Outcomes among Patients Prescribed Suboptimal Antibiotic Therapy on Discharge to Nursing Homes
Abstract Background Little is known regarding outcomes for patients prescribed antibiotics on discharge from the hospital to nursing homes (NHs). We quantified the association between suboptimal antibiotic prescribing and clinical outcomes at discharge to NHs. Methods This was a multicenter, retrospective cohort study of adult (age >18 years) patients prescribed systemic antibiotics on discharge from 9 acute care hospitals in Oregon, Washington, and Wisconsin to a NH from 2016 – 2018. Study data were electronically extracted from hospital and NH electronic health records and supplemented with chart review. Suboptimal antibiotic therapy was determined by an infectious disease pharmacist or physician using clinical information (e.g., antibiotic regimen, indication, and culture results) available at discharge. Outcomes included emergency department (ED) visits, hospital readmissions, or Clostridioides difficile infection (CDI) within 30 days of hospital discharge. Comparison of outcomes between patients with suboptimal and non-suboptimal antibiotic therapy were tested by chi-squared tests. Results Among 280 included patients, mean (SD) age was 76.0 (11.5) years, 35.7% (n=100) were male, and median (IQR) inpatient length of stay was 6 (4-9) days. The most prevalent antibiotic indications were urinary tract infections (n =109, 38.9%), lung indications (n=60, 21.4%), and prophylaxis (n=29, 10.4%). Among 317 antibiotic prescriptions, the most frequently prescribed antibiotic classes were cephalosporins (n=83, 29.6%), fluoroquinolones (n=57, 20.4%), and beta-lactam/beta-lactamase-inhibitors (n=40, 14.3%). Fifty-eight patients (20.7%) were prescribed suboptimal antibiotic therapy on hospital discharge. There were no significant differences in the frequency of 30-day ED visits (14% vs 11%, p=0.76) or hospital readmission (19% vs 18%, p=0.94) between patients prescribed and not prescribed suboptimal antibiotics; however, suboptimal antibiotics were significantly associated with CDI within 30 days of discharge (10% vs 2%, p=0.01). Conclusion Suboptimal antibiotic prescribing on discharge to NHs was associated with increased risk of CDI within 30 days of discharge. This finding may inform interventions to improve antibiotic prescribing on discharge to NHs. Disclosures YoungYoon Ham, PharmD, Gilead: Honoraria Jon P. Furuno, PhD, Merck & Co., Inc: Grant/Research Support
Integrating Community Voices in Data-Centric Research: Overcoming Barriers to Meaningful Engagement
Importance Normothermic machine perfusion (NMP) has been shown to reduce peritransplant complications. Despite increasing NMP use in liver transplant (LT), there is a scarcity of real-world clinical experience data. Objective To compare LT outcomes between donation after brain death (DBD) and donation after circulatory death (DCD) allografts preserved with NMP or static cold storage (SCS). Design, Setting, and Participants This single-center, retrospective observational cohort study included all consecutive adult LTs performed between January 2019 and December 2023 at the Mayo Clinic in Arizona. Data analysis was performed between February 2024 and June 2024. Outcomes of DBD-SCS, DBD-NMP, DCD-SCS, and DCD-NMP transplants were compared. Exposure DBD and DCD livers preserved on NMP or SCS. Main Outcomes and Measures The primary outcomes were early allograft dysfunction (EAD), intraoperative transfusion, and post-LT hospital resource use, including length of stay (LOS) and readmissions. Secondary outcomes included acute kidney injury (AKI) and 1-year graft and patient survival. Results A total of 1086 LTs were included in the following 4 groups: DBD-SCS (n = 480), DBD-NMP (n = 63), DCD-SCS (n = 264), and DCD-NMP (n = 279). Among LT recipients, median (IQR) age was 60.0 years (52.0-66.0); 399 LT recipients (36.7%) were female. DCD-NMP had the lowest EAD rate (17.5%), followed by DCD-SCS (50.0%), DBD-NMP (36.8%), and DBD-SCS (27.3%) ( P &lt; .001). DCD-NMP had the lowest intraoperative transfusion requirement compared to all other groups. Hospital and intensive care unit (ICU) LOS were shortest in DCD-NMP (median [IQR] hospital LOS, 5.0 days [4.0-7.0]; P = .01; median [IQR] ICU LOS, 1.5 days [1.2-3.1]; P = .01). One-year cumulative readmission probability was 86% lower for DCD-NMP vs DCD-SCS (95% CI, 0.09-0.22; P &lt; .001) and 53% lower for DBD-NMP vs DBD-SCS (95% CI, 0.26-0.87; P &lt; .001). AKI events were lower in DCD-NMP (31.1%) vs DCD-SCS (47.4%) ( P = .001). Compared to SCS, the NMP group had a 78% overall reduction in graft failure (hazard ratio [HR], 0.22; 95% CI, 0.10-0.49; P &lt; .001). For those receiving DCD allografts, the risk reduction was even more pronounced, with an 87% decrease in graft failure (HR, 0.13; 95% CI, 0.05-0.33; P &lt; .001). NMP was significantly protective from patient mortality vs SCS (HR, 0.31; 95% CI, 0.12-0.80; P = .02). Conclusions and Relevance In this observational high-volume cohort study, NMP significantly improved LT clinical outcomes and reduced hospital resource use, especially in DCD allografts. NMP may enhance access to LT by addressing the challenges historically linked with DCD liver use.
Tumor tissue modified viral (TTMV)-HPV DNA as a biomarker of treatment efficacy for definitive chemoradiation in anal squamous cell carcinoma: A step towards truly personalized therapy.
10 Background: Cell-free circulating tumor tissue modified viral DNA (ctDNA) has been used as a biomarker to detect recurrence for anal squamous cell carcinoma (ASCC). However, its value in informing treatment modification during definitive chemoradiation (CRT) has yet to be explored. We evaluated ctDNA response during and at completion of definitive CRT to establish patterns of disease response and inform future studies to personalize treatment. Methods: From 11/2022 to 6/2024, 13 consecutive patients with biopsy proven, non-metastatic ASCC received definitive CRT and had ctDNA testing using a commercially available droplet digital quantitative PCR assay. ctDNA testing was done at baseline (pre-CRT), week 4 of CRT, and/or end of CRT, 1-3 months post-CRT, and every 6 months thereafter. CRT included concurrent 5FU/MMC (or capecitabine/MMC) and radiotherapy according to RTOG 0529. Treatment response assessment included: physical exam, anoscopy, and imaging with PET/CT, CT C/A/P +/- MRI abdomen and pelvis. Results: 13 patients had ctDNA testing and 11 patients had HPV-positive ASCC and tested positive for ctDNA. The 11 patients with detectable baseline ctDNA were included in this analysis. The median age at diagnosis was 63 years old. Staging included: 1- Stage IIA, 7- Stage IIB, 1- Stage IIIA, 2- Stage IIIC. 1 patient was cN0, while 11 were cN1. With a median follow-up from completion of CRT of 13 months, 4 patients have persistent or recurrent disease: 2 with distant metastases, 1 with persistent local disease (1 month post-CRT), and 1 with local and distant recurrence. Baseline value of ctDNA did not correlate to stage at diagnosis, rate of clearance during CRT, or likelihood of recurrence. 5 of 11 patients cleared ctDNA by week 4 of CRT. Of 5 patients who cleared ctDNA by week 4 of CRT, 4 remain NED and 1 developed distant metastases. Of 6 patients with persistent ctDNA at week 4 of CRT, 3 have persistent or recurrent disease- 1 local persistence 1 month post-CRT, 1 local and distant recurrence 6 months post-CRT, and 1 with distant recurrence 12 months post- CRT. Among 6 patients who cleared ctDNA by the final week of CRT, 1 patient developed recurrent disease. Among the 4 patients in the series with residual/recurrent disease, 3 of them had not cleared ctDNA by the end of CRT. Of 10 patients with ctDNA testing at 1 month post-CRT, 8 had no detectable ctDNA. 2 patients with persistent (1) or recurrent (1) ctDNA at 1 month post-CRT developed disease recurrence- 1 with distant recurrence and 1 with local and distant recurrence. Conclusions: ctDNA assessment during CRT may provide insight into disease response that can predict patterns of failure and facilitate personalized therapy- treatment intensification, deintensification, or additional testing to detect early metastatic disease. Larger studies and clinical validation are needed.
PD-1 prelimits both the cytotoxic and exhaustion potential in thymic CD8+ T cells and impacts the maintenance of peripheral tumor immunity
Abstract Durable T cell immunity against cancer depends on the continual replenishment of effector CD8+ T cells. Thymic output has been correlated with favorable prognosis in cancer patients across a range of ages, suggesting that the thymus is an important source for replenishing T cells capable of controlling cancer progression. However, the effector potential of thymic mature CD8+ T cells and their regulation have not been clearly defined. In this study, we identified the ability of thymic single positive CD8+ T cells to gain effector potential after thymic selection, but they are subject to the regulation of PD-1. We found a previously undisclosed role of PD-1 in limiting both the cytotoxic and exhaustion potential of thymic and peripheral CD8+ T cells. Our results show that although PD-1 inhibition facilitates the expansion of effector CD8+ T cells, effector CD8+ cells gradually lose their antitumor activity within tumor tissues due to advanced exhaustion in the absence of PD-1. Thus, although the preset effector potential in thymic mature CD8+ T cells allows them to rapidly respond to malignant cells in the periphery, PD-1, as a checkpoint, is embedded in the thymic mature CD8+ T cells after positive selection to balance their effector function from exaggeration and exhaustion. Therefore, we propose that a strategy capable of upholding the cytotoxic capacity and avoiding exhaustion of CD8+ T cells during the early stages of PD-1 inhibition therapy is needed to achieve durable antitumor immunity.