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Objectives/Goals: Our objectives were to determine enteric microbiome characteristics in fluoroquinolone-resistant Enterobacterales (FQRE)-colonized and non-FQRE-colonized hematopoietic cell transplant (HCT recipients, and to understand the enteric microbiome-specific factors associated with the development of FQRE BSI in FQRE-colonized HCT recipients. Methods/Study Population: This was a prospective cohort study of patients undergoing HCT at Weill Cornell Medicine from November 2016 to August 2019. All participants received levofloxacin prophylaxis during post-HCT neutropenia. Stool samples were collected prior to levofloxacin prophylaxis initiation and during the week after HCT. Our overall study population consisted of 26 FQRE-colonized HCT recipients and 69 non-FQRE-colonized HCT recipients. Samples underwent selective quantitative culture for FQRE, as well as 16S rRNA sequencing. Raw sequence data were processed and aligned to a custom SILVA database. Analysis of 16S rRNA sequencing was conducted in R using phyloseq. Results/Anticipated Results: We saw significant differences in microbiome composition in comparing pre-HCT samples from FQRE-colonized HCT recipients to non-FQRE-colonized HCT recipients, including significantly higher relative abundances of Bacteroidales and Enterobacterales in colonized recipients. MaAslin2 demonstrated significantly differential abundance of Bacteroides and Escherichia-Shigella ASVs. We observed a significant decrease in Enterobacterales relative abundance in non-FQRE-colonized recipients after HCT, but no such change in FQRE-colonized recipients. FQRE-colonized recipients who developed FQRE BSI had a lower relative abundance of Bacteroidales as compared to those who did not. No significant difference in FQRE colonization density as measured by quantitative FQRE stool culture was observed. Discussion/Significance of Impact: FQRE-colonized HCT recipients represent a unique subgroup of HCT recipients. Colonized HCT recipients with FQRE BSI had lower relative abundance of Bacteroidales compared to those without BSI. Further work is needed to determine the mechanism behind this association and to further characterize the microbiome in this subgroup of HCT recipients.
Objectives/Goals: Common mamographic findings, breast arterial calcifications (BAC), are a sex-specific biomarker for cardiovascular disease in women. While less common, BAC is frequently encountered on mammograms in males. This study aims to investigate BAC and its association with cardiovascular risk factors in men. Methods/Study Population: A retrospective single-institution study of male patients with mammography studies was performed between September 1, 2018, and September 3, 2025. Diagnostic mammographic images of male patients from a high-volume breast imaging facility were evaluated for the presence of BAC. BAC severity will be assigned a score based on the Canadian Society of Breast Imaging’s grading system. Unique ICD-10 diagnosis codes from the electronic medical record that have been established as independent risk factors for cardiovascular disease will also be reviewed. Male patients who have a prior history of myocardial infarction, coronary revascularization, stroke, heart failure, peripheral vascular disease, breast cancer, dementia, or chronic dialysis/renal transplant were excluded. Results/Anticipated Results: The study is in process of pulling male mammograms from our institution. Current volume of male mammograms at the institution is about 160 male mammograms performed per month. Therefore, we anticipate having around 13,600 male mammograms to analyze the BAC presence. Anticipated results include that patients with independent cardiovascular risk factors such as increased systolic blood pressure, increased LDL levels, and current smokers will have a higher prevalence of BAC presence. Additionally, those with a presence of BAC will be older compared to those that have an absence of BAC on mammography. If BAC is shown to be a significant risk factor for the development of cardiovascular disease, perhaps a mammogram might be recommended in men purely for cardiovascular risk assessment. Discussion/Significance of Impact: A significant association between the presence of BAC and CVD risk factors may provide a supplementary assessment of CVD risk among men, offering a novel tool for risk stratification. Implementing a standardized BAC reporting model may allow for earlier identification of asymptomatic patients at high risk for adverse cardiac events.
Objectives/Goals: The objective of this study was to evaluate the performance of multimodal machine learning (ML) models trained to predict differentiated thyroid cancer (DTC) recurrence using clinical data combined with novel natural language processing (NLP) derived features extracted from patient cytopathology and surgical pathology reports. Methods/Study Population: This was a retrospective study of adult thyroid cancer patients treated at an academic medical center. Patients were classified as having cancer recurrence or no recurrence. NLP features were extracted from cytopathology and surgical pathology reports using Term Frequency–Inverse Document Frequency (TF-IDF), latent Dirichlet allocation (LDA), and a zero-shot large language model (LLM) classification. 5 multimodal ML models were trained to predict cancer recurrence utilizing a combination of NLP and LLM features and clinical variables. Model performance was evaluated using area under the receiver operating characteristic curve (ROC-AUC) and precision recall area under the curve (PR-AUC). The top performing model was optimized with a 5-fold cross-validation. Feature importance was calculated. Results/Anticipated Results: 480 patients with differentiated thyroid cancer diagnosed on surgical pathology were included in this study. The baseline model (clinical variables only) had a F1-score of 0.52 and an AUC of 0.53. The optimized gradient boosting model utilizing all features (EMR, LDA, TF-IDF, and LLM) had a F1-score of 0.87 and an AUC of 0.86. Topic words and themes from the patient cytopathology and surgical pathology reports were generated using LDA. Topic themes in cytopathology reports include malignancy, lymph node evaluation, and molecular testing. Topic themes in surgical pathology reports include histologic subtype, orientation of nodule, and intraoperative biopsy. The LDA themes of malignancy and histologic subtype ranked the highest in terms of feature importance. Discussion/Significance of Impact: Multimodal models utilizing novel NLP features derived from unstructured pathology reports may enable improved prediction of recurrence in patients with DTC. Our optimized model demonstrated that 4 of the top 6 highest features were LDA topics. Topic modeling may be a valuable tool to extract relevant information from unstructured clinical notes.
Our academic medical center has offered a cooperative education position in infection prevention and control (IPC) to undergraduate students since 2005. We describe the position and surveyed prior participants (n = 16)—all reported a valuable experience, and 6 of 16 (38%) reported subsequent employment in full-time IPC positions during their careers.
The US Centers for Disease Control and Prevention (CDC) has listed vaccination as one the top 10 public health achievements,1 and vaccines have led to a tremendous reduction in deaths due to vaccine-preventable disease in the United States alone.2 There are over 22 million persons employed in healthcare in the United States, making healthcare personnel (HCP) an important population to target for vaccination efforts. Promoting vaccination for HCP as defined by the CDC is likely to become even more essential given the rising incidence in the United States of vaccine-preventable diseases such as measles and pertussis.3
Interior design is the result of a range of designed elements being brought together to produce an orchestrated space. Just as the interior spaces that accommodate much of our lives are designed, so the sensory experiences we have in those spaces are also designed, whether by professionals or by householders. Some interiors are put together with all of the senses in mind while others prioritise one sense over the rest, for example in appealing to the eye. This chapter examines a variety of ways in which interior designers, mediators and consumers accommodate and stimulate the sense of touch. Landmark examples of designers’ appeal to the hand range from Adolf Loos’ furry bedroom for Lina Loos to the smooth plastic curves favoured by Charles and Ray Eames, Verner Panton and, latterly, Karim Rashid, and demonstrated too in the ubiquitous Monobloc chair. By foregrounding touch in design ideation or production, mediation and consumption, this chapter offers an alternative to interior design histories which focus exclusively on eye appeal.
Dry ecosystems are critical to the global carbon cycle. Seasonally dry tropical ecosystems as a whole are botanically megadiverse, yet we have little understanding of how diversity impacts aboveground carbon, which is particularly noticeable for insular Asia. Across 133 vegetation plots on the seasonally dry tropical island of Flores, we used spatially explicit models to determine how land use impacts aboveground carbon stocks and whether this is dependent upon multidimensional diversity. Carbon is greatest in primary forests and least in agricultural landscapes. However, we find that land use interacts with phylogenetic and species diversity to shape carbon stocks. Across almost all models, quadratic effects of diversity were better predictors of carbon, indicating that whilst the initial build-up of diversity increases carbon, greater diversity causes carbon decline. Results suggest that future conservation plans will be needed to balance carbon storage with multidimensional diversity, which may offer distinct benefits for ecosystem resilience and services.
Community-acquired bacterial pneumonia (CABP) contributes significantly to mortality and healthcare costs worldwide. The use of guideline-concordant antibiotic therapy for CABP is associated with improved outcomes.
Methods:
This was a retrospective cohort study of inpatients with CABP due to MRSA or P. aeruginosa in the All of Us database. The proportion of patients on guideline-concordant antibiotics or guideline-discordant antibiotics was compared within groups based upon patient age, sex, self-reported race, ethnicity, marital status, alcohol use, and tobacco use. Guideline concordance was determined using the 2019 IDSA/ATS CABP guidelines. Associations were further analyzed using multivariate logistic regression.
Results:
A total of 336 patients with CABP due to MRSA (152) or P. aeruginosa (184) were included. Guideline-concordant antibiotic therapy was prescribed to 70% of CABP-MRSA patients and for 57% of CABP-P. aeruginosa patients. Independently predictive factors of guideline-concordant antibiotic prescribing for CABP-P. aeruginosa patients were Non-Hispanic Black (NHB) vs. Non-Hispanic White (NHW) race (odds ratio = 0.30, 95% confidence interval = 0.12 – 0.75).
Conclusion:
In the All of Us database, the majority of CABP-MRSA and CABP-P. aeruginosa patients were prescribed guideline-concordant antibiotic therapy. Race was independently predictive of guideline-concordant antibiotic therapy for patients with CABP-P. aeruginosa, but not CABP-MRSA. NHB patients were less likely to receive guideline-concordant antibiotic therapy than NHW patients when treated for CABP-P. aeruginosa.
This article introduces item response models for rating relational data. The relational data are obtained via ratings of senders and receivers in a directed network. The proposed models allow comparisons of senders and receivers on a one-dimensional latent scale while accounting for unobserved homophilic relationships. We show that the approach effectively captures reciprocity and clustering phenomena in the relational data. We estimate model parameters using a Bayesian specification and utilize Markov Chain Monte Carlo methods to approximate the full conditional posterior distributions. Simulation studies demonstrate that model parameters can be recovered satisfactorily even when the dimensionality of the network is small. We also present an extensive empirical application to illustrate the usefulness of the proposed models for complete and incomplete networks.
Most people with mental illness in low and middle-income countries (LMICs) do not receive biomedical treatment, though many seek care from traditional healers and faith healers. We conducted a qualitative study in Buyende District, Uganda, using framework analysis. Data collection included interviews with 24 traditional healers, 20 faith healers, and 23 biomedical providers, plus 4 focus group discussions. Interviews explored treatment approaches, provider relationships, and collaboration potential until theoretical saturation was reached. Three main themes emerged: (1) Biomedical providers’ perspectives on traditional and faith healers; (2) Traditional and faith healers’ views on biomedical providers; and (3) Collaboration opportunities and barriers. Biomedical providers viewed faith healers positively but traditional healers as potentially harmful. Traditional and faith healers valued biomedical approaches while feeling variably accepted. Interest in collaboration existed across groups but was complicated by power dynamics, economic concerns, and differing mental illness conceptualizations. Traditional healers and faith healers routinely referred patients to biomedical providers, though reciprocal referrals were rare. The study reveals distinct dynamics among providers in rural Uganda, with historical colonial influences continuing to shape relationships and highlighting the need for integrated, contextually appropriate mental healthcare systems.
We investigate whether firm-level political connections affect the allocation of exemptions from tariffs imposed on $US 550 billion of Chinese goods imported to the United States annually beginning in 2018. Evidence points to politicians not only rewarding supporters but also punishing opponents: Past campaign contributions to the party controlling (in opposition to) the executive branch increase (decrease) approval likelihood. Our findings point to quid pro quo arrangements between politicians and firms, as opposed to the “information” channel linking political access to regulatory outcomes.
Low- and middle-income countries (LMICs) bear a disproportionate burden of mental illness, with limited access to biomedical care. This study examined pathways to care for psychosis in rural Uganda, exploring factors influencing treatment choices.
Methods
We conducted a mixed-methods study in Buyende District, Uganda, involving 67 in-depth interviews and 4 focus group discussions (data collection continued until thematic saturation was reached) with individuals with psychotic disorders, family members, and local leaders. Structured questionnaires were administered to 41 individuals with psychotic disorders.
Results
Three main themes emerged: (1) Positive attitudes towards biomedical providers, (2) Barriers to accessing biomedical care (3) Perceived etiologies of mental illness that influenced care-seeking behaviors. While 81% of participants eventually accessed biomedical care, the median time to first biomedical contact was 52 days, compared to 7 days for any care modality.
Conclusions
Despite a preference for biomedical care, structural barriers and diverse illness perceptions led many to seek pluralistic care pathways. Enhancing access to biomedical services and integrating traditional and faith healers could improve mental health outcomes in rural Uganda.
Background: Health equity is a critical consideration in public health research, emphasizing the importance of fair and just access to healthcare resources. This study explores the impact of health equity factors on the incidence rates of Central Line-Associated Bloodstream Infections (CLABSI) and Methicillin-Resistant Staphylococcus aureus (MRSA) across diverse healthcare facilities in Louisiana. Methods: We conducted a comprehensive analysis utilizing 2022 data from the National Healthcare Safety Network (NHSN). Fourteen healthcare facilities were randomly selected from nine regions in Louisiana, with guidance from the 2022 NHSN external validation toolkit. Key health equity factors from Health Resources and Service Administration (HRSA) were assessed, including urbanicity, MUA/P, and HPSA_Primary Care. Risk ratios were calculated to quantify the association between these health equity factors and the incidence rates of CLABSI and MRSA. Results: The findings reveal intriguing insights into the relationship between health equity factors and infection rates. In urban settings, the risk of CLABSI was lower (Risk Ratio: 0.634, 95% CI: 0.2442–1.646), contrasting with a significantly higher risk of MRSA (Risk Ratio: 1.7, 95% CI: 1.119–2.582). This suggests a complex interplay between urbanicity and the specific infection types. For MUA/P, no significant impact on CLABSI rates was observed (Risk Ratio: 0.963, 95% CI: 0.4225–2.195), but an increased risk of MRSA emerged (Risk Ratio: 1.652, 95% CI: 1.029–2.652). In healthcare professional shortage areas for primary care (HPSA_Primary Care), both CLABSI (Risk Ratio: 1.37, 95% CI: 0.5854–3.204) and MRSA (Risk Ratio: 2.098, 95% CI: 1.305–3.372) exhibited elevated risks, though only MRSA risk was statistically significant. Conclusions: This research underscores the nuanced relationship between health equity factors and infection rates in healthcare facilities. Urban settings may contribute to a lower risk of CLABSI but a higher risk of MRSA, emphasizing the need for tailored preventive strategies. Living in medically underserved areas appears to heighten the risk of MRSA, warranting targeted interventions. Additionally, healthcare professional shortage areas for primary care demonstrate potential associations with increased risks for both CLABSI and MRSA. These findings provide valuable insights for public health practitioners, policymakers, and healthcare administrators aiming to address health disparities and enhance infection control measures in diverse healthcare settings. Further research is encouraged to unravel the multifaceted dynamics influencing infection rates and to inform targeted interventions for improved health outcomes.
Background: Antimicrobial resistance is a growing problem in Candida spp., leading to treatment challenges and increased morbidity and mortality. The World Health Organization (WHO) fungal priority pathogens list classifies C. glabrata, C. tropicalis, and C. parapsilosis as high priority and leading causes of candidemia with high fluconazole resistance. In the US, these organisms are the most frequently isolated non-albicans Candida species. In 2016, the Antibiotic Resistance Laboratory Network (ARLN) was created to monitor resistance threats, including in Candida spp. This study describes the proportion of resistance in C. glabrata, C. parapsilosis, and C. tropicalis isolates sent to the Southeast ARLN from 2017 to 2023. Methods: This study evaluated C. glabrata, C. parapsilosis, and C. tropicalis submitted to the Southeast ARLN from Alabama, Florida, Georgia, Louisiana, Mississippi, and Tennessee from February 2017- September 2023. Species identification was confirmed by Bruker Biotyper matrix assisted laser desorption-ionization time of flight (MALDI-TOF). Antifungal susceptibility testing (AFST) was performed using TREK frozen broth microdilution panels. Minimum inhibitory concentration values from the clinical instrument were used to determine susceptibility based on Clinical and Laboratory Standards Institute (CLSI) standard interpretations from the 2020 CLSI M60 guidelines. Data were extracted from the laboratory information management system. Analyses were conducted using SAS v9.4. Results: AFST testing was performed on 660 C. glabrata, 500 C. parapsilosis, and 233 C. tropicalis isolates from within the Southeast region. The predominant specimen sources by species were blood 25.30% C. glabrata; other/not specified 27.80% C. parapsilosis; and lower respiratory 36.91% C. tropicalis. Resistance to fluconazole is as follows: C. glabrata, 12.88%; C. parapsilosis, 3.41%; C. tropicalis, 36.64%. Resistance to voriconazole is as follows: C. parapsilosis, 1.00%; C. tropicalis 30.04%. Resistance to at least one echinocandin (Anidulafungin, Capsofungin, Micafungin) is as follows: C. glabrata, 1.67%; C. parapsilosis, 0.60%; C. tropicalis, 0.43%. Overall, there was a decreasing trend in resistance to fluconazole, and voriconazole in all three species between 2017 and 2023. Conclusions: Antifungal resistance in non-albicans Candida species represents an emerging public health threat, however, within the Southeast region, ARLN data has shown a decreasing trend of azole resistance. This may be due in part to changes in reporting requirements and submission criteria from within the region. Nevertheless, C. tropicalis showed high resistance to azoles within the Southeast region. These Candida species should be monitored to inform clinical decision making and identify resistance patterns in other US regions due to their increase in resistance worldwide.
OBJECTIVES/GOALS: In this study, we aim to report the role of porins and blaCTX-M β-lactamases among Escherichia coli and Klebsiella pneumoniae, focusing on emerging carbapenem resistant Enterobacterales (CRE) subtypes, including non-carbapenemase producing Enterobacterales (NCPE) and ertapenem-resistant but meropenem-susceptible (ErMs) strains. METHODS/STUDY POPULATION: Whole genome sequencing was conducted on 76 carbapenem-resistant isolates across 5 hospitals in San Antonio, U.S. Among these, NCP isolates accounted for the majority of CRE (41/76). Identification and antimicrobial susceptibility testing (AST) results were collected from the clinical charts. Repeat speciation was determined through whole genome sequencing (WGS) analysis and repeat AST, performed with microdilution or ETEST®. Minimum inhibitory concentrations (MIC) were consistent with Clinical and Laboratory Standards Institute (CLSI M100, ED33). WGS and qPCR were used to characterize the resistome of all clinical CRE subtypes, while western blotting and liquid chromatography with tandem mass spectrometry (LC-MS-MS) were used to determine porin expression and carbapenem hydrolysis, respectively. RESULTS/ANTICIPATED RESULTS: blaCTX-Mwas found to be most prevalent among NCP isolates (p = 0.02). LC-MS/MS analysis of carbapenem hydrolysis revealed that blaCTX-M-mediated carbapenem hydrolysis, indicating the need to reappraise the term, “non-carbapenemase (NCP)®” for quantitatively uncharacterized CRE strains harboring blaCTX-M. Susceptibility results showed that 56% of all NCPE isolates had an ErMs phenotype (NCPE vs. CPE, p < 0.001), with E. coli driving the phenotype (E. coli vs. K. pneumoniae, p < 0.001). ErMs strains carrying blaCTX-M, had 4-fold more copies of blaCTX-M than ceftriaxone-resistant but ertapenem-susceptible isolates (3.7 v. 0.9, p < 0.001). Immunoblot analysis demonstrated the absence of OmpC expression in NCP-ErMs E. coli, with 92% of strains lacking full contig coverage ofompC. DISCUSSION/SIGNIFICANCE: Overall, this work provides evidence of a collaborative effort between blaCTX-M and OmpC in NCP strains that confer resistance to ertapenem but not meropenem. Clinically, CRE subtypes are not readily appreciated, potentially leading to mismanagement of CRE infected patients. A greater focus on optimal treatments for CRE subtypes is needed.
This article builds a bridge between research on the queer economy and that on the mixed economy of welfare by developing the ‘queer economy of welfare mix’ framework. While the two fields are related, there is a lack of discussion about the queer dimensions of the mixed economy of welfare or the mixed strategies employed by lesbian, gay, bisexual, trans, and queer (LGBTQ+) individuals to explore the benefits and limitations of the queer economy. The purpose of our framework is to show how local and transnational goods provided by the mixed economy of welfare can enable LGBTQ+ individuals to organise their welfare through the mixed strategies – citizen strategy, consumer strategy, and consumer-citizen strategy. By examining Taiwan’s legalised same-sex marriage and its impact on Hong Kong and Mainland China, we demonstrate the empirical significance of the framework, which serves as an analytical tool for examining the government’s role in promoting LGBTQ+ individuals’ welfare and the challenges involved.
While previous research has repeatedly indicated that greater BMI was associated with reduced cognitive performance, emerging literature on BMI and cognition in late life (age 65 and above) shows conflicting results. Recent studies (Luchsinger et al., 2013; Arvanitakis, Capuano, Bennett, & Barnes, 2018) have found that high BMI was associated with improved processing speed and verbal memory performance in older adults, but further research is needed to examine this relationship across additional aspects of cognition. The current study aims to build upon recent literature by exploring the relationship between BMI and four cognitive domains across the adult age span.
Participants and Methods:
Adults between the ages of 25-84 (n=217) were recruited for the Loma Linda University Healthy Avocado Trial study. Participants had a mean age of 49.61 (SD=13.13), mean education of 14.66 years (SD=2.44), and a mean BMI of 33.87 (SD=5.48). Cognition was measured using a two-hour neurocognitive battery divided into four discrete domains: attention/working memory (Digit Span, Auditory Consonant Trigrams), processing speed (Trail Making Test Part A, Stroop Color, Stroop Word, Symbol Digit Modalities Test), executive function (FAS/Phonemic Fluency, Stroop Word-Color, Trail Making Test Part B), and learning/memory (Rey Auditory Verbal Learning Test [RAVLT], Brief Visuospatial Memory Test-Revised [BVMT-R]). Individual test scores were standardized around the sample means and standard deviations, and cognitive domain scores were calculated as an average of the relevant standardized scores; a global cognition score represents the average of tests across all four domains. Participants were divided into three age groups (25-40, 41-60, and 61-84). Correlational analyses were performed between BMI and cognitive domain scores within each age group, while controlling for age, sex, and education.
Results:
No significant correlations were observed between BMI and any of the cognitive domains among adults aged 25-40 and 41-60. Among adults aged 61-84, a significant association was found between BMI and learning and memory (r=0.390, p=0.011). An examination of individual subtests within the domain revealed significant positive correlations between BMI and RAVLT short delay recall (r=0.338, p=0.029) and long delay recall (r=0.353, p=0.022), and between BMI and BVMT-R immediate- (r=0.351, p=0.023) and delayed recall (r=0.332, p=0.032). A trend for the association between BMI on global cognition was also observed in the oldest age group (r=0.275, p=0.078). No significant associations were observed between BMI and the domains of attention/working memory, processing speed, or executive function.
Conclusions:
No significant associations were observed between BMI and cognitive performance among young- and middle-aged adults. However, among older adults aged 6184, higher BMI was associated with higher scores on both verbal and nonverbal learning & memory. These findings support the 'obesity paradox,' suggesting that increased BMI may be protective for elderly adults. Multiple explanations for this relationship have been proposed, including the role of BMI in the body’s inflammatory response system, as well as observations of dementia-related weight loss. Further research is needed to determine whether BMI has a protective benefit, or if it is simply a clinical marker of underlying disease.
We developed the Shell Game Task (SGT) as a novel Performance Validity Test (PVT). While most PVTs use a forced-choice paradigm with “memory” as the primary domain being assessed, the SGT is a face-valid measure of attention and working memory. We explored the accuracy of the SGT to detect noncredible performance using a simulatordesign study.
Participants and Methods:
Ninety-four university students were randomly assigned to either best effort (CON) (n=49) or simulating traumatic brain injury (TBI) (SIM) (n=45) conditions. Participants completed a full battery of neuropsychological tests to simulate an actual evaluation, including the Test of Memory Malingering (TOMM) and the SGT. The SGT involves three cups and a red ball shown on the screen. Participants watch as the ball is placed under one of the three cups. Cups are then shuffled. Participants are asked to track the cup that contains the ball and correctly identify its location. We created two difficulty levels (easy vs hard, 20 trials each) by changing the number of times the cups were shuffled. Participants were given feedback (correct vs incorrect) after each trial. At the conclusion of the study, participants were asked about adherence to study directions they were given.
Results:
Participants with missing data (CON=1; SIM=2) or who reported non-adherence to study directions (CON=2; SIM=1) were removed from analyses. Twenty-five percent in SIM and 0% in CON failed TOMM
Trial 2 (<45) suggesting adequate manipulation of groups. Groups were not different in age, gender, ethnicity, or education (all p’s>.05). There were 9 participants in each group with concussion/TBI history. TBI history was not significantly related to performance on the SGT in either group, although participants with TBI history tended to do better. Average performances on TOMM Trial 1 (36.62 vs 47.91, p<.001) and TOMM Trial 2 (37.50 vs 49.71, p<.001) were significantly lower in the SIM group. Performance on SGT was also significantly lower in the SIM group across SGT Total Correct (20.17 vs 24.65 of 40, p=.008), SGT Easy (10.60 vs 13.52 of 20, p=.002), and SGT Hard (9.57 vs 11.13 of 20, p=.068). Mixed ANOVA showed a trend towards significant group by SGT difficulty interaction (F(1,86)=3.41, p=.052, np2=.043). There was steeper decline in performance on SGT Hard compared to SGT Easy for CON. ROC analyses suggested adequate but not ideal sensitivity/specificity: scores <8 on SGT Easy (sensitivity=26%; false positive=11%), <7 on SGT Hard (sensitivity=26%; false positive=7%), and <15 on SGT Total (sensitivity=24%; false positive=9%).
Conclusions:
These preliminary data indicate the SGT may be able to detect malingered TBI. However, additional development of this measure is necessary. Further refinement of difficulty level may improve sensitivity/specificity (e.g., CON mean performance for SGT Easy trails was 13.52, suggesting the items may be too difficult). This study was limited to an online administration due to COVID, which could have affected results; future studies should test inperson administration of the SGT. In addition, performance in clinical control groups (larger samples of individuals with mild TBI, ADHD) should be tested to better determine specificity for these preliminary cutoffs.
One common concern amongst the aging population is that of worsening memory. Speed of processing and executive functions are also areas of age-related decline that affect daily living. Lifestyle modifications such as diet, exercise, and sleep have garnered intense interest as potential methods to prevent or delay cognitive decline. Among dietary factors, omega-3 fatty acids (FAs) have been documented as containing a myriad of health benefits, including neuroprotective effects. The aim of this study is to examine the associations between omega-3 FAs, cognitive function, and neuroanatomical regions of interest in a healthy aging population.
Participants and Methods:
Adults aged 65 and older (n=40, 48.9% Female) were recruited for the Loma Linda University Adventist Health Study-2 Cognitive and Neuroimaging Substudy. Participants had a mean age of 76.25 years (SD=8.29), 16.78 years of education (SD=2.53), and were predominantly White (85.0%). Participants received a two-hour neurocognitive battery, including measures of immediate and delayed memory (Rey Auditory Verbal Learning Test, RAVLT; WMS-IV Logical Memory, LM), processing speed (Stroop), and executive functions (Stroop Color/Word). Participants underwent brain imaging on a 3T Siemens MRI, including a 3D T1-weighted MPRAGE sequence. Cortical reconstruction and volumetric segmentation were performed using FreeSurfer software. Blood samples were collected for fatty acid analysis. Individual FAs were expressed as a percent of total FAs. An omega-3 index was constructed as the sum of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) FAs. Correlational analyses, controlling for age, sex, and education, investigated relationships between omega-3 levels (individual and index) and (a) cognitive function (immediate and delayed memory, processing speed, executive functions), and (b) brain volumes in specific regions of interest (hippocampus, entorhinal cortex, frontal pole, white matter).
Results:
EPA was significantly positively correlated with Stroop Color (r=.34, p=.048). Although not statistically significant, trends were observed between the omega-3 index and Stroop Color (r=.30, p=.08), and between both DHA and the omega-3 index with RAVLT – delayed recall (r=.29, p=.095; r=.30, p=.08, respectively). With regards to regional brain volumes, EPA and the omega-3 index were both significantly positively correlated with the entorhinal cortex (r=.34, p=.041; r=.41, p=.01, respectively) and white matter volume (r=.36, p=.028; r=.34, p=.038, respectively). DHA was significantly positively correlated with white matter volume (r=.34, p=.044).
Conclusions:
Blood levels of EPA were positively correlated with a measure of processing speed, and trends were observed between DHA, the omega-3 index and[GN1] verbal memory, and between the omega-3 index and processing speed. We also found that omega-3 FA values were associated with greater brain volume in the entorhinal cortex and white matter in our sample of healthy older adults. Atrophy of the entorhinal cortex has been associated with pathological processes. Additionally, white matter is known to effect processing speed. These findings may offer support for the idea that omega-3 FAs exert their neuroprotective effects by fortifying areas of the brain, specifically the entorhinal cortex and white matter, that promote maintenance of cognitive function in late life.