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Shorter antibiotic courses and transition to oral therapy for uncomplicated gram-negative bloodstream infections (GN-BSI) are evidence-supported yet remain challenging to implement. Here we report our experience with a GN-BSI antimicrobial stewardship (AS) quality improvement initiative in a large health system.
Methods:
We implemented two sequential AS interventions in adult patients hospitalized with uncomplicated GN-BSI: (1) mandatory AS review of patients discharging on intravenous (IV) antibiotics (“OPAT review”) and (2) a clinical guideline informing oral antibiotic transition and duration, in our 22-hospital system. We evaluated the initiative from January 2018 to September 2024. Pre- and postimplementation rates of (1) IV antibiotics at discharge and (2) total length of antibiotic therapy were calculated across the following periods: preintervention, after OPAT review, and after guideline implementation. Secondary outcomes included duration <10 days, oral antibiotic prescribing, and guideline-recommended dosing.
Results:
3,231 patients (preintervention: 666, postOPAT review: 1,357, postguideline: 1,208) were included. We observed decreases in IV antibiotics at discharge (22.7% preintervention, 10.7% postOPAT review, and 9.2% postguideline, p < 0.001) and median length of treatment (13.5 days preintervention to 10.7 days postguideline, p < 0.001). We also observed improvement in durations <10 days (19.1% vs 45%, p < 0.001), oral antibiotic prescriptions, and appropriate dosing (2.8% vs 33.5%, p < 0.001), but no difference in rates of BSI recurrence, mortality, or C. difficile infection.
Conclusion:
After implementing GN-BSI-focused AS initiatives in our large health system, we observed a shift toward more frequent oral rather than IV antibiotics at discharge, and shorter overall antibiotic durations, without obvious changes in adverse outcomes.
We surveyed physicians and patients to create a novel Desirability of outcome ranking (DOOR) for non-severe community-acquired pneumonia (CAP). Patients generally ranked uncomfortable but non-life-threatening symptoms as less desirable, while physicians focused on traditional medical outcomes. When developing DOORs, both patient and clinician perspectives should be considered.
Background: Dichotomous outcomes rarely capture the range of potential outcomes important to patients and clinicians. To address this limitation, the Desirability of Outcome Ranking (DOOR) score was created to rank potential outcomes from least to most desirable. Currently, there is no standardized method to develop a DOOR score and data are limited on whether patients and their clinicians rank outcomes similarly. We aimed: (a) to develop a novel DOOR score for adults hospitalized with community-acquired pneumonia (CAP) by surveying patients and clinicians on their preferred outcome ranking and (b) to compare their relative DOOR rankings. Methods: We created nine clinical scenarios describing the spectrum of potential outcomes of patients with CAP two weeks after initial emergency department visit. To ascertain clinician DOOR score, we used a snowball sampling method to recruit a target of 25 clinicians in specialties that regularly treat CAP. For the patient DOOR score, we recruited patients hospitalized with CAP by reviewing electronic patient lists for adults hospitalized with pneumonia. Respondents were asked to rank the 9 cases from most to least desirable in REDCap. To create the final DOOR score, we used Friedman rank sum tests to combine/collapse DOOR outcomes with scores that did not significantly differ. We used the Mann Whitney U test to compare DOOR rankings between physicians and patients. Final study results were presented to a national hospital medicine patient and family advisory committee (PFAC) for their impressions. Results: 22 patients (71% response rate) and 25 clinicians responded to our DOOR survey. Their ranked order of DOOR outcomes is shown in Table 1. Combining non-significantly different DOOR outcomes resulted in collapsing of 6 cases into 2 categories for 5 overall DOOR scores that significantly differed from each other (Table 1 for final ranking). Patients and clinicians had significantly different preferred ranking for 6 DOOR cases. Our PFAC had several hypotheses as to why rankings differed (Table 2). Conclusion: We present a novel DOOR score derived from patient and clinician reported preferences for outcomes of hospitalized adult patients with CAP. Clinicians and patients differed in their perception of certain outcomes with patients ranking symptoms that were uncomfortable but not potentially life-threatening as less desirable than physicians. Physicians tended to rank quality linked metrics such as readmission as worse than patients. When designing future trials using DOOR scores, researchers should consider including patients in DOOR score design as their perspectives may differ from clinicians.
Genetic research on nicotine dependence has utilized multiple assessments that are in weak agreement.
Methods
We conducted a genome-wide association study (GWAS) of nicotine dependence defined using the Diagnostic and Statistical Manual of Mental Disorders (DSM-NicDep) in 61,861 individuals (47,884 of European ancestry [EUR], 10,231 of African ancestry, and 3,746 of East Asian ancestry) and compared the results to other nicotine-related phenotypes.
Results
We replicated the well-known association at the CHRNA5 locus (lead single-nucleotide polymorphism [SNP]: rs147144681, p = 1.27E−11 in EUR; lead SNP = rs2036527, p = 6.49e−13 in cross-ancestry analysis). DSM-NicDep showed strong positive genetic correlations with cannabis use disorder, opioid use disorder, problematic alcohol use, lung cancer, material deprivation, and several psychiatric disorders, and negative correlations with respiratory function and educational attainment. A polygenic score of DSM-NicDep predicted DSM-5 tobacco use disorder criterion count and all 11 individual diagnostic criteria in the independent National Epidemiologic Survey on Alcohol and Related Conditions-III sample. In genomic structural equation models, DSM-NicDep loaded more strongly on a previously identified factor of general addiction liability than a “problematic tobacco use” factor (a combination of cigarettes per day and nicotine dependence defined by the Fagerström Test for Nicotine Dependence). Finally, DSM-NicDep showed a strong genetic correlation with a GWAS of tobacco use disorder as defined in electronic health records (EHRs).
Conclusions
Our results suggest that combining the wide availability of diagnostic EHR data with nuanced criterion-level analyses of DSM tobacco use disorder may produce new insights into the genetics of this disorder.
Despite recent attention to the increased risk of cognitive impairment in older adults with essential tremor (ET), there are only limited data on the trajectories of cognitive change in ET or the demographic and motor predictors of such change.
Method:
This study included 148 cognitively normal individuals with ET (mean age = 76.7 ± 9.7 years) at baseline and had at least one follow-up evaluation (mean years of observation = 5.2 ± 1.6). Generalized Estimating Equations examined rates of change in six composite cognitive outcomes as a function of time, as well as demographic (age, sex, and education) and motor predictors (tremor severity, age of tremor onset, presence of rest tremor, cranial tremor, intention tremor, tandem gait) of rates of change. Demographics, medication use, and mood symptoms at baseline were covariates for all models.
Results:
Participants evidenced a decline in global cognition, executive function, and attention (prange = <0.001–0.044) over time. Older age predicted faster decline in all cognitive outcomes except attention (prange=<0.001–0.025). Tremor severity predicted faster decline in executive function (p = 0.011). Rest tremor predicted faster decline in executive function and attention (p = 0.033, 0.017). Tandem gait missteps predicted faster decline in memory and visuospatial ability (p = 0.026, 0.028).
Conclusions:
Results point to a dissociation in the predictive value of different motor features for specific aspects of cognitive decline. These results shed light on the earliest manifestations of cognitive impairment in older adults with ET and implicate different pathways by which heterogeneous cognitive changes emerge.
Current evidence underscores a need to transform how we do clinical research, shifting from academic-driven priorities to co-led community partnership focused programs, accessible and relevant career pathway programs that expand opportunities for career development, and design of trainings and practices to develop cultural competence among research teams. Failures of equitable research translation contribute to health disparities. Drivers of this failed translation include lack of diversity in both researchers and participants, lack of alignment between research institutions and the communities they serve, and lack of attention to structural sources of inequity and drivers of mistrust for science and research. The Duke University Research Equity and Diversity Initiative (READI) is a program designed to better align clinical research programs with community health priorities through community engagement. Organized around three specific aims, READI-supported programs targeting increased workforce diversity, workforce training in community engagement and cultural competence, inclusive research engagement principles, and development of trustworthy partnerships.
Objectives/Goals: Manual skin assessment in chronic graft-versus-host disease (cGVHD) can be time consuming and inconsistent (>20% affected area) even for experts. Building on previous work we explore methods to use unmarked photos to train artificial intelligence (AI) models, aiming to improve performance by expanding and diversifying the training data without additional burden on experts. Methods/Study Population: Common to many medical imaging projects, we have a small number of expert-marked patient photos (N = 36, n = 360), and many unmarked photos (N = 337, n = 25,842). Dark skin (Fitzpatrick type 4+) is underrepresented in both sets; 11% of patients in the marked set and 9% in the unmarked set. In addition, a set of 20 expert-marked photos from 20 patients were withheld from training to assess model performance, with 20% dark skin type. Our gold standard markings were manual contours around affected skin by a trained expert. Three AI training methods were tested. Our established baseline uses only the small number of marked photos (supervised method). The semi-supervised method uses a mix of marked and unmarked photos with human feedback. The self-supervised method uses only unmarked photos without any human feedback. Results/Anticipated Results: We evaluated performance by comparing predicted skin areas with expert markings. The error was given by the absolute difference between the percentage areas marked by the AI model and expert, where lower is better. Across all test patients, the median error was 19% (interquartile range 6 – 34) for the supervised method and 10% (5 – 23) for the semi-supervised method, which incorporated unmarked photos from 83 patients. On dark skin types, the median error was 36% (18 – 62) for supervised and 28% (14 – 52) for semi-supervised, compared to a median error on light skin of 18% (5 – 26) for supervised and 7% (4 – 17) for semi-supervised. Self-supervised, using all 337 unmarked patients, is expected to further improve performance and consistency due to increased data diversity. Full results will be presented at the meeting. Discussion/Significance of Impact: By automating skin assessment for cGVHD, AI could improve accuracy and consistency compared to manual methods. If translated to clinical use, this would ease clinical burden and scale to large patient cohorts. Future work will focus on ensuring equitable performance across all skin types, providing fair and accurate assessments for every patient.
While clinical research intends to improve health outcomes for all, access to research participation is often limited and inequitable. Geographic proximity is a recognized barrier, thus, systemic infrastructure solutions through federal programs including General Clinical Research Centers and Clinical and Translational Science Awards have sought to improve accessibility. Even with such support, academic medical centers often have limited clinical research-dedicated space apart from shared exam rooms in difficult-to-navigate hospitals or clinics. In 2019, the Duke University School of Medicine looked beyond its medical center campus to identify free-standing sites within Durham communities for participant study visits. Catalyzed by the COVID-19 pandemic, Duke Research at Pickett, a 22 000-square-foot building with a laboratory, 30 exam rooms, and on-site parking, opened in October 2020 to support vaccine and treatment trials. Upon the lifting of many COVID-19 restrictions, and in partnership with the Research Equity and Diversity Initiative (READI) Community Advisory Council, the building was transformed to encourage community gatherings, education, and training programs. To date, Duke Research at Pickett has hosted 2692 participants in 78 research trials and 14 community-engaged activities.
The field of healthcare epidemiology is increasingly focused on identifying, characterizing, and addressing social determinants of health (SDOH) to address inequities in healthcare quality. To identify evidence gaps, we examined recent systematic reviews examining the association of race, ethnicity, and SDOH with inpatient quality measures.
Methods:
We searched Medline via OVID for English language systematic reviews from 2010 to 2022 addressing race, ethnicity, or SDOH domains and inpatient quality measures in adults using specific topic questions. We imported all citations to Covidence (www.covidence.org, Veritas Health Innovation) and removed duplicates. Two blinded reviewers assessed all articles for inclusion in 2 phases: title/abstract, then full-text review. Discrepancies were resolved by a third reviewer.
Results:
Of 472 systematic reviews identified, 39 were included. Of these, 23 examined all-cause mortality; 6 examined 30-day readmission rates; 4 examined length of stay, 4 examined falls, 2 examined surgical site infections (SSIs) and one review examined risk of venous thromboembolism. The most evaluated SDOH measures were sex (n = 9), income and/or employment status (n = 9), age (n = 6), race and ethnicity (n = 6), and education (n = 5). No systematic reviews assessed medication use errors or healthcare-associated infections. We found very limited assessment of other SDOH measures such as economic stability, neighborhood, and health system access.
Conclusion:
A limited number of systematic reviews have examined the association of race, ethnicity and SDOH measures with inpatient quality measures, and existing reviews highlight wide variability in reporting. Future systematic evaluations of SDOH measures are needed to better understand the relationships with inpatient quality measures.
Historically, psychiatric conditions and neurodegenerative diseases have been considered differential diagnoses in older adults with cognitive impairment. However, recent evidence has shown that neuropsychiatric symptoms may be prodromal for neurodegenerative disease. Subjective Cognitive Decline (SCD) is a potential marker for pre-clinical Alzheimer’s Disease (AD) that is frequently related to mood disturbances. Delineating the relationship between neuropsychiatric symptoms, SCD, and cognitive impairment will help to define both the independent and combined utility of SCD and neuropsychiatric symptoms as markers of preclinical AD. This abstract uses the DSM-5 Cross-Cutting Measure (DSM-5 CC), a novel comprehensive screening tool for psychiatric symptoms, to examine the relationship between objective and subjective measures of cognition as they relate to neuropsychiatric symptoms.
Participants and Methods:
27 community dwelling, cognitively diverse older adults (78% female, mean age 71.9 ± 7) were enrolled in the Concerns about Memory Problems (CAMP) study. Inclusion criteria included the expressed concern about memory functioning by participants on a 5-item screener, while exclusion criteria were defined as previous diagnosis of neurodegenerative diseases and/or major stroke. All participants completed neuropsychological testing and study surveys including the DSM-5 CC. Participants completed Level 1 and all Level 2 (L2) forms of the DSM-5 CC. Spearman two-tailed non-parametric correlations and independent samples t-tests were conducted to examine the relationship between the DSM-5 CC and the 5-item subjective cognition screener, as well as the DSM-5 CC and objective cognition results.
Results:
Subjective measures of cognition, as measured by answers to the 5-item screening measure, were significantly associated with DSM-5 CC measures. Question 1 on the SCD screener which asks, “Compared to others your age, do you have difficulty with memory or thinking abilities?” was associated with anger (p=.033) and depression (p=.018) L2 forms. Question 3, “Do any difficulties with memory or thinking abilities make it difficult for you to do things in daily life?)” was associated with the L2 forms for somatic symptoms (p=.016) and repetitive thoughts and behaviors (p<.001). Objective measures of cognition from neuropsychological testing also correlated with DSM-5 CC sub-scores. Digits Backwards Length (DBL) correlated with DSM-5 CC Level 1 Sum (r= -.57, p=.002). DBL (r=-.59 p=.001) and Digits Backwards Total Correct (DBTC) (r=-.47, p=.013) associated with somatic symptoms L2 and sleep L2 (DBL: r=,-.45 p=.019; DBTC: r=-.39, p=.044). Category Naming (animals) was also associated with anxiety L2 (r=-.42, p=.030).
Conclusions:
Subjective and objective measures of cognition were each related to sub-scores of the DSM-5 CC. Interestingly, the associations were largely non-overlapping. These results highlight the importance of considering a wide range of neuropsychiatric symptoms in the assessment of SCD and cognitive impairment. Findings contribute to the growing body of literature suggesting that neuropsychiatric symptoms should be studied in conjunction with cognitive symptoms among older adults as co-occurring phenomena. Future directions will need to include longitudinal studies that can examine the prodromal nature of SCD and neuropsychiatric symptoms for Alzheimer’s and other neurodegenerative disorders.
Clinical trials face many challenges with meeting projected enrollment and retention goals. A study’s recruitment materials and messaging convey necessary key information and therefore serve as a critical first impression with potential participants. Yet study teams often lack the resources and skills needed to develop engaging, culturally tailored, and professional-looking recruitment materials. To address this gap, the Recruitment Innovation Center recently developed a Recruitment & Retention Materials Content and Design Toolkit, which offers research teams guidance, actionable tips, resources, and customizable templates for creating trial-specific study materials. This paper seeks to describe the creation and contents of this new toolkit.
The Recruitment Innovation Center (RIC) has created a toolkit of novel strategies to engage potential participants in response to recruitment and retention challenges associated with COVID-19 studies. The toolkit contains pragmatic, generalizable resources to help research teams increase awareness of clinical trials and opportunities to participate; produce culturally sensitive and engaging recruitment materials; improve consent and return of results processes; and enhance recruitment of individuals from populations disproportionately impacted by COVID-19. This resource, the “RIC COVID-19 Recruitment and Retention Toolkit,” is available free online. We describe the toolkit and the community feedback used to author and curate this resource.
Efforts to improve antimicrobial prescribing are occurring within a changing healthcare landscape, which includes the expanded use of telehealth technology. The wider adoption of telehealth presents both challenges and opportunities for promoting antimicrobial stewardship. Telehealth provides 2 avenues for remote infectious disease (ID) specialists to improve inpatient antimicrobial prescribing: telehealth-supported antimicrobial stewardship and tele-ID consultations. Those 2 activities can work separately or synergistically. Studies on telehealth-supported antimicrobial stewardship have reported a reduction in inpatient antimicrobial prescribing, cost savings related to less antimicrobial use, a decrease in Clostridioides difficile infections, and improved antimicrobial susceptibility patterns for common organisms. Tele-ID consultation is associated with fewer hospital transfers, a shorter length of hospital stay, and decreased mortality. The implementation of these activities can be flexible depending on local needs and available resources, but several barriers may be encountered. Opportunities also exist to improve antimicrobial use in outpatient settings. Telehealth provides a more rapid mechanism for conducting outpatient ID consultations, and increasing use of telehealth for routine and urgent outpatient visits present new challenges for antimicrobial stewardship. In primary care, urgent care, and emergency care settings, unnecessary antimicrobial use for viral acute respiratory tract infections is common during telehealth encounters, as is the case for fact-to-face encounters. For some diagnoses, such as otitis media and pharyngitis, antimicrobials are further overprescribed via telehealth. Evidence is still lacking on the optimal stewardship strategies to improve antimicrobial prescribing during telehealth encounters in ambulatory care, but conventional outpatient stewardship strategies are likely transferable. Further work is warranted to fill this knowledge gap.
A single high-fat, high-carbohydrate meal (HFHC) results in elevated postprandial glucose (GLU), triglycerides (TAG) and metabolic load index (MLI; TAG (mg/dl) + GLU (mg/dl)) that contributes to chronic disease risk. While disease risk is higher in older adults (OA) compared to younger adults (YA), the acute effects of exercise on these outcomes in OA is understudied. Twelve YA (age 23.3 ± 3.9 yrs, n = 5 M/7 F) and 12 OA (age 67·7 ± 6.0 yrs, n = 8 M/4 F) visited the laboratory in random order to complete a HFHC with no exercise (NE) or acute exercise (EX) condition. EX was performed 12 hours prior to HFHC at an intensity of 65 % of maximal heart rate to expend 75 % of the kcals consumed in HFHC (Marie Callender’s Chocolate Satin Pie; 12 kcal/kgbw; 57 % fat, 37 % CHO). Blood samples were taken at 0, 30, 60, 90 minutes, and then every hour until 6 hours post-meal. TAG levels increased to a larger magnitude in OA (Δ∼61 ± 31 %) compared to YA (Δ∼37 ± 34 %, P < 0·001), which were attenuated in EX compared to NE (P < 0·05) independent of age. There was no difference in GLU between OA and YA after the HFM, however, EX had attenuated GLU independent of age (NE: Δ∼21 ± 26 %; EX: Δ∼12 ± 18 %, P = 0·027). MLI was significantly lower after EX compared to NE in OA and YA (P < 0·001). Pre-prandial EX reduced TAG, GLU and MLI post-HFHC independent of age.
Fama, or fame, is a central concern of late medieval literature. Where fame came from, who deserved it, whether it was desirable, how it was acquired and kept were significant inquiries for a culture that relied extensively on personal credit and reputation. An interest in fame was not new, being inherited from the classical world, but was renewed and rethought within the vernacular revolutions of the later Middle Ages. The work of Geoffrey Chaucer shows a preoccupation with ideas on the subject of fama, not only those received from the classical world but also those of his near contemporaries; via an engagement with their texts, he aimed to negotiate a place for his own work in the literary canon, establishing fame as the subject-site at which literary theory was contested and writerly reputation won. Chaucer's place in these negotiations was readily recognized in his aftermath, as later writers adopted and reworked postures which Chaucer had struck, in their own bids for literary place. This volume considers the debates on fama which were past, present and future to Chaucer, using his work as a centre point to investigate canon formation in European literature from the late Middle Ages and into the Early Modern period. Isabel Davis is Senior Lecturer in Medieval Literature at Birkbeck, University of London; Catherine Nall is Senior Lecturer in Medieval Literature at Royal Holloway, University of London. Contributors: Joanna Bellis, Alcuin Blamires, Julia Boffey, Isabel Davis, Stephanie Downes, A.S.G. Edwards, Jamie C. Fumo, Andrew Galloway, Nick Havely, Thomas A. Prendergast, Mike Rodman Jones, William T. Rossiter, Elizaveta Strakhov.
We sought to contain a healthcare-associated coronavirus disease 2019 (COVID-19) outbreak, to evaluate contributory factors, and to prevent future outbreaks.
All patients and staff on the outbreak ward (case cluster), and randomly selected patients and staff on COVID-19 wards (positive control cluster) and a non-COVID-19 wards (negative control cluster) underwent reverse-transcriptase polymerase chain reaction (RT-PCR) testing. Hand hygiene and personal protective equipment (PPE) compliance, detection of environmental SARS-COV-2 RNA, patient behavior, and SARS-CoV-2 IgG antibody prevalence were assessed.
Results:
In total, 145 staff and 26 patients were exposed, resulting in 24 secondary cases. Also, 4 of 14 (29%) staff and 7 of 10 (70%) patients were asymptomatic or presymptomatic. There was no difference in mean cycle threshold between asymptomatic or presymptomatic versus symptomatic individuals. None of 32 randomly selected staff from the control wards tested positive. Environmental RNA detection levels were higher on the COVID-19 ward than on the negative control ward (OR, 19.98; 95% CI, 2.63–906.38; P < .001). RNA levels on the COVID-19 ward (where there were no outbreaks) and the outbreak ward were similar (OR, 2.38; P = .18). Mean monthly hand hygiene compliance, based on 20,146 observations (over preceding year), was lower on the outbreak ward (P < .006). Compared to both control wards, the proportion of staff with detectable antibodies was higher on the outbreak ward (OR, 3.78; 95% CI, 1.01–14.25; P = .008).
Conclusion:
Staff seroconversion was more likely during a short-term outbreak than from sustained duty on a COVID-19 ward. Environmental contamination and PPE use were similar on the outbreak and control wards. Patient noncompliance, decreased hand hygiene, and asymptomatic or presymptomatic transmission were more frequent on the outbreak ward.
Spinal muscular atrophy (SMA) is a devastating rare disease that affects individuals regardless of ethnicity, gender, and age. The first-approved disease-modifying therapy for SMA, nusinursen, was approved by Health Canada, as well as by American and European regulatory agencies following positive clinical trial outcomes. The trials were conducted in a narrow pediatric population defined by age, severity, and genotype. Broad approval of therapy necessitates close follow-up of potential rare adverse events and effectiveness in the larger real-world population.
Methods:
The Canadian Neuromuscular Disease Registry (CNDR) undertook an iterative multi-stakeholder process to expand the existing SMA dataset to capture items relevant to patient outcomes in a post-marketing environment. The CNDR SMA expanded registry is a longitudinal, prospective, observational study of patients with SMA in Canada designed to evaluate the safety and effectiveness of novel therapies and provide practical information unattainable in trials.
Results:
The consensus expanded dataset includes items that address therapy effectiveness and safety and is collected in a multicenter, prospective, observational study, including SMA patients regardless of therapeutic status. The expanded dataset is aligned with global datasets to facilitate collaboration. Additionally, consensus dataset development aimed to standardize appropriate outcome measures across the network and broader Canadian community. Prospective outcome studies, data use, and analyses are independent of the funding partner.
Conclusion:
Prospective outcome data collected will provide results on safety and effectiveness in a post-therapy approval era. These data are essential to inform improvements in care and access to therapy for all SMA patients.
We describe an ultra-wide-bandwidth, low-frequency receiver recently installed on the Parkes radio telescope. The receiver system provides continuous frequency coverage from 704 to 4032 MHz. For much of the band (${\sim}60\%$), the system temperature is approximately 22 K and the receiver system remains in a linear regime even in the presence of strong mobile phone transmissions. We discuss the scientific and technical aspects of the new receiver, including its astronomical objectives, as well as the feed, receiver, digitiser, and signal processor design. We describe the pipeline routines that form the archive-ready data products and how those data files can be accessed from the archives. The system performance is quantified, including the system noise and linearity, beam shape, antenna efficiency, polarisation calibration, and timing stability.
Patients with essential tremor exhibit heterogeneous cognitive functioning. Although the majority of patients fall under the broad classification of cognitively “normal,” essential tremor is associated with increased risk for mild cognitive impairment and dementia. It is possible that patterns of cognitive performance within the wide range of normal functioning have predictive utility for mild cognitive impairment or dementia. These cross-sectional analyses sought to determine whether cognitive patterns, or “clusters,” could be identified among individuals with essential tremor diagnosed as cognitively normal. We also determined whether such clusters, if identified, were associated with demographic or clinical characteristics of patients.
Methods:
Elderly subjects with essential tremor (age >55 years) underwent comprehensive neuropsychological testing. Domain means (memory, executive function, attention, visuospatial abilities, and language) from 148 individuals diagnosed as cognitively normal were partitioned using k-means cluster analysis. Individuals in each cluster were compared according to cognitive functioning (domain means and test scores), demographic factors, and clinical variables.
Results:
There were three clusters. Cluster 1 (n = 64) was characterized by comparatively low memory scores (p < .001), Cluster 2 (n = 39) had relatively low attention and visuospatial scores (p < .001), and Cluster 3 (n = 45) exhibited consistently high performance across all domains. Cluster 1 had lower Montreal Cognitive Assessment scores and reported more prescription medication use and lower balance confidence.
Conclusions:
Three patterns of cognitive functioning within the normal range were evident and tracked with certain clinical features. Future work will examine the extent to which such patterns predict conversion to mild cognitive impairment and/or dementia.