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Network modeling has been applied in a range of trauma-exposed samples, yet results are limited by an over reliance on cross-sectional data. The current analyses used posttraumatic stress disorder (PTSD) symptom data collected over a 5-year period to estimate a more robust between-subject network and an associated symptom change network.
Methods
A PTSD symptom network is measured in a sample of military veterans across four time points (Ns = 1254, 1231, 1106, 925). The repeated measures permit isolating between-subject associations by limiting the effects of within-subject variability. The result is a highly reliable PTSD symptom network. A symptom slope network depicting covariation of symptom change over time is also estimated.
Results
Negative trauma-related emotions had particularly strong associations with the network. Trauma-related amnesia, sleep disturbance, and self-destructive behavior had weaker overall associations with other PTSD symptoms.
Conclusions
PTSD's network structure appears stable over time. There is no single ‘most important’ node or node cluster. The relevance of self-destructive behavior, sleep disturbance, and trauma-related amnesia to the PTSD construct may deserve additional consideration.
To examine the association between adherence to plant-based diets and mortality.
Design:
Prospective study. We calculated a plant-based diet index (PDI) by assigning positive scores to plant foods and reverse scores to animal foods. We also created a healthful PDI (hPDI) and an unhealthful PDI (uPDI) by further separating the healthy plant foods from less-healthy plant foods.
Setting:
The VA Million Veteran Program.
Participants:
315 919 men and women aged 19–104 years who completed a FFQ at the baseline.
Results:
We documented 31 136 deaths during the follow-up. A higher PDI was significantly associated with lower total mortality (hazard ratio (HR) comparing extreme deciles = 0·75, 95 % CI: 0·71, 0·79, Ptrend < 0·001]. We observed an inverse association between hPDI and total mortality (HR comparing extreme deciles = 0·64, 95 % CI: 0·61, 0·68, Ptrend < 0·001), whereas uPDI was positively associated with total mortality (HR comparing extreme deciles = 1·41, 95 % CI: 1·33, 1·49, Ptrend < 0·001). Similar significant associations of PDI, hPDI and uPDI were also observed for CVD and cancer mortality. The associations between the PDI and total mortality were consistent among African and European American participants, and participants free from CVD and cancer and those who were diagnosed with major chronic disease at baseline.
Conclusions:
A greater adherence to a plant-based diet was associated with substantially lower total mortality in this large population of veterans. These findings support recommending plant-rich dietary patterns for the prevention of major chronic diseases.
To examine the use of telemedicine among Canadian concussion providers and clinics before and after the COVID-19 pandemic onset and identify barriers and facilitators for future use.
Methods:
Ninety-nine concussion clinics and healthcare providers across Canada that offered one or more clinical concussion-related service were identified using standardized online searches and approached to complete a cross-sectional online survey.
Results:
Thirty clinics or providers completed the survey and two completed subsections of the survey (response rate of 32.3%). Only 28.1% of respondents indicated that they used telemedicine to provide care prior to the COVID-19 pandemic. Providers most commonly using telemedicine prior to the pandemic were occupational therapists and physicians, while the most commonly used services were in-person videoconferencing and eConsultation. Most respondents (87%) indicated their clinic’s use of telemedicine changed following the onset of the COVID-19 pandemic including new use of in-person video-conferencing, telephone calls, and eConsultation. Ninety-three percent indicated that they would consider using telemedicine to provide care to their concussion patients once the pandemic was over. Barriers needed to be overcome to facilitate use or greater use of telemedicine-based services were the inability to conduct a complete physical examination, lack of appropriate reimbursement, lack of start-up, and maintenance funding and medico-legal risk.
Conclusion:
Telemedicine was used by a minority of Canadian concussion clinics and providers prior to the COVID-19 pandemic but was rapidly adopted by many facilities. This study provides important insight into the factors that must be considered to optimize use of telemedicine in concussion care in the future.
Liquid-electron microscopy (EM), the room-temperature correlate to cryo-EM, is a rapidly growing field providing high-resolution insights of macromolecules in solution. Here, we describe how liquid-EM experiments can incorporate automated tools to propel the field to new heights. We demonstrate fresh workflows for specimen preparation, data collection, and computing processes to assess biological structures in liquid. Adeno-associated virus (AAV) and the SARS-CoV-2 nucleocapsid (N) were used as model systems to highlight the technical advances. These complexes were selected based on their major differences in size and natural symmetry. AAV is a highly symmetric, icosahedral assembly with a particle diameter of ~25 nm. At the other end of the spectrum, N protein is an asymmetric monomer or dimer with dimensions of approximately 5–7 nm, depending upon its oligomerization state. Equally important, both AAV and N protein are popular subjects in biomedical research due to their high value in vaccine development and therapeutic efforts against COVID-19. Overall, we demonstrate how automated practices in liquid-EM can be used to decode molecules of interest for human health and disease.
The spatial and temporal extent of severe acute respiratory coronavirus virus 2 (SARS-CoV-2) environmental contamination has not been precisely defined. We sought to elucidate contamination of different surface types and how contamination changes over time.
Methods:
We sampled surfaces longitudinally within COVID-19 patient rooms, performed quantitative RT-PCR for the detection of SARS-CoV-2 RNA, and modeled distance, time, and severity of illness on the probability of detecting SARS-CoV-2 using a mixed-effects binomial model.
Results:
The probability of detecting SARS-CoV-2 RNA in a patient room did not vary with distance. However, we found that surface type predicted probability of detection, with floors and high-touch surfaces having the highest probability of detection: floors (odds ratio [OR], 67.8; 95% credible interval [CrI], 36.3–131) and high-touch elevated surfaces (OR, 7.39; 95% CrI, 4.31–13.1). Increased surface contamination was observed in room where patients required high-flow oxygen, positive airway pressure, or mechanical ventilation (OR, 1.6; 95% CrI, 1.03–2.53). The probability of elevated surface contamination decayed with prolonged hospitalization, but the probability of floor detection increased with the duration of the local pandemic wave.
Conclusions:
Distance from a patient’s bed did not predict SARS-CoV-2 RNA deposition in patient rooms, but surface type, severity of illness, and time from local pandemic wave predicted surface deposition.
We prospectively surveyed SARS-CoV-2 RNA contamination in staff common areas within an acute-care hospital. An increasing prevalence of surface contamination was detected over time. Adjusting for patient census or community incidence of coronavirus disease 2019 (COVID-19), the proportion of contaminated surfaces did not predict healthcare worker COVID-19 infection on study units.
Eggs contain important compounds related to enhanced cognition, but it is not clear if egg consumption, as a whole, has a direct impact on memory decline in older adults. This study aimed to determine whether egg intake levels predict the rate of memory decline in healthy older adults after sociodemographic and dietary controls. We conducted a secondary analysis of data from 470 participants, age 50 and over, from the Biospsychosocial Religion and Health Study. Participants completed a food frequency questionnaire, which was used to calculate egg intake and divide participants into Low (<23 g/week, about half an egg), Intermediate (24–63 g/week, half to 1½ eggs) and High (≥63 g/week, about two or more eggs) tertiles. Participants were administered the California Verbal Learning Test – 2nd Edition (CVLT-II) Short Form in 2006–2007, and 294 of them were again tested in 2010–2011. Using linear mixed model analysis, no significant cross-sectional differences were observed in CVLT-II performance between egg intake levels after controlling for age, sex, race, education, body mass index, cardiovascular risk, depression and intake of meat, fish, dairy and fruits/vegetables. Longitudinally, the Intermediate egg group exhibited significantly slower rates of decline on the CVLT-II compared to the Low egg group. The High egg group also exhibited slower rates of decline, but not statistically significant. Thus, limited consumption of eggs (about 1 egg/week) was associated with slower memory decline in late life compared to consuming little to no eggs, but a dose-response effect was not clearly evident. This study may help explain discrepancies in previous research that did not control for other dietary intakes and risk factors.
Multidrug-resistant organisms (MDROs) colonizing the healthcare environment have been shown to contribute to risk for healthcare-associated infections (HAIs), with adverse effects on patient morbidity and mortality. We sought to determine how bacterial contamination and persistent MDRO colonization of the healthcare environment are related to the position of patients and wastewater sites.
Methods:
We performed a prospective cohort study, enrolling 51 hospital rooms at the time of admitting a patient with an eligible MDRO in the prior 30 days. We performed systematic sampling and MDRO culture of rooms, as well as 16S rRNA sequencing to define the environmental microbiome in a subset of samples.
Results:
The probability of detecting resistant gram-negative organisms, including Enterobacterales, Acinetobacter spp, and Pseudomonas spp, increased with distance from the patient. In contrast, Clostridioides difficile and methicillin-resistant Staphylococcus aureus were more likely to be detected close to the patient. Resistant Pseudomonas spp and S. aureus were enriched in these hot spots despite broad deposition of 16S rRNA gene sequences assigned to the same genera, suggesting modifiable factors that permit the persistence of these MDROs.
Conclusions:
MDRO hot spots can be defined by distance from the patient and from wastewater reservoirs. Evaluating how MDROs are enriched relative to bacterial DNA deposition helps to identify healthcare micro-environments and suggests how targeted environmental cleaning or design approaches could prevent MDRO persistence and reduce infection risk.
The objectives were to examine clinical characteristics, length of recovery, and the prevalence of delayed physician-documented recovery, compare clinical outcomes among those with sport-related concussion (SRC) and non-sport-related concussion (nSRC), and identify risk factors for delayed recovery.
Methods:
Included patients (8–18 years) were assessed ≤14 days post-injury at a multidisciplinary concussion program and diagnosed with an acute SRC or nSRC. Physician-documented clinical recovery was defined as returning to pre-injury symptom status, attending full-time school without symptoms, completing Return-to-Sport strategy as needed, and normal physical examination. Delayed physician-documented recovery was defined as >28 days post-injury.
Results:
Four hundred and fifteen patients were included (77.8% SRC). There was no difference in loss of consciousness (SRC: 9.9% vs nSRC: 13.0%, p = 0.39) or post-traumatic amnesia (SRC: 24.1% vs SRC: 31.5%, p = 0.15) at the time of injury or any differences in median Post-Concussion Symptom Scale scores (SRC: 20 vs nSRC: 23, p = 0.15) at initial assessment. Among those with complete clinical follow-up, the median physician-documented clinical recovery was 20 days (SRC: 19 vs nSRC: 23; p = 0.37). There was no difference in the proportion of patients who developed delayed physician-documented recovery (SRC: 27.7% vs nSRC: 36.1%; p = 0.19). Higher initial symptom score increased the risk of delayed physician-documented recovery (IRR: 1.39; 95% CI: 1.29, 1.49). Greater material deprivation and social deprivation were associated with an increased risk of delayed physician-documented recovery.
Conclusions:
Most pediatric concussion patients who undergo early medical assessment and complete follow-up appear to make a complete clinical recovery within 4 weeks, regardless of mechanism.
United States dentists prescribe 10% of all outpatient antibiotics. Assessing appropriateness of antibiotic prescribing has been challenging due to a lack of guidelines for oral infections. In 2019, the American Dental Association (ADA) published clinical practice guidelines (CPG) on the management of acute oral infections. Our objective was to describe baseline national antibiotic prescribing for acute oral infections prior to the release of the ADA CPG and to identify patient-level variables associated with an antibiotic prescription.
Design:
Cross-sectional analysis.
Methods:
We performed an analysis of national VA data from January 1, 2017, to December 31, 2017. We identified cases of acute oral infections using International Classification of Disease, Tenth Revision, Clinical Modification (ICD-10-CM) codes. Antibiotics prescribed by a dentist within ±7 days of a visit were included. Multivariable logistic regression identified patient-level variables associated with an antibiotic prescription.
Results:
Of the 470,039 VA dental visits with oral infections coded, 12% of patient visits with irreversible pulpitis, 17% with apical periodontitis, and 28% with acute apical abscess received antibiotics. Although the median days’ supply was 7, prolonged use of antibiotics was frequent (≥8 days, 42%–49%). Patients with high-risk cardiac conditions, prosthetic joints, and endodontic, implant, and oral and maxillofacial surgery dental procedures were more likely to receive antibiotics.
Conclusions:
Most treatments of irreversible pulpitis and apical periodontitis cases were concordant with new ADA guidelines. However, in cases where antibiotics were prescribed, prolonged antibiotic courses >7 days were frequent. These findings demonstrate opportunities for the new ADA guidelines to standardize and improve dental prescribing practices.
Due to shortages of N95 respirators during the coronavirus disease 2019 (COVID-19) pandemic, it is necessary to estimate the number of N95s required for healthcare workers (HCWs) to inform manufacturing targets and resource allocation.
Methods:
We developed a model to determine the number of N95 respirators needed for HCWs both in a single acute-care hospital and the United States.
Results:
For an acute-care hospital with 400 all-cause monthly admissions, the number of N95 respirators needed to manage COVID-19 patients admitted during a month ranges from 113 (95% interpercentile range [IPR], 50–229) if 0.5% of admissions are COVID-19 patients to 22,101 (95% IPR, 5,904–25,881) if 100% of admissions are COVID-19 patients (assuming single use per respirator, and 10 encounters between HCWs and each COVID-19 patient per day). The number of N95s needed decreases to a range of 22 (95% IPR, 10–43) to 4,445 (95% IPR, 1,975–8,684) if each N95 is used for 5 patient encounters. Varying monthly all-cause admissions to 2,000 requires 6,645–13,404 respirators with a 60% COVID-19 admission prevalence, 10 HCW–patient encounters, and reusing N95s 5–10 times. Nationally, the number of N95 respirators needed over the course of the pandemic ranges from 86 million (95% IPR, 37.1–200.6 million) to 1.6 billion (95% IPR, 0.7–3.6 billion) as 5%–90% of the population is exposed (single-use). This number ranges from 17.4 million (95% IPR, 7.3–41 million) to 312.3 million (95% IPR, 131.5–737.3 million) using each respirator for 5 encounters.
Conclusions:
We quantified the number of N95 respirators needed for a given acute-care hospital and nationally during the COVID-19 pandemic under varying conditions.
Insomnia is a common, distressing, and impairing psychological outcome experienced by informal caregivers (ICs) of patients with cancer. Cognitive behavioral therapy for insomnia (CBT-I) and acupuncture both have known benefits for patients with cancer, but such benefits have yet to be evaluated among ICs. The purpose of the present study was to evaluate the feasibility, acceptability and preliminary effects of CBT-I and acupuncture among ICs with moderate or greater levels of insomnia.
Method
Participants were randomized to eight sessions of CBT-I or ten sessions of acupuncture.
Results
Results highlighted challenges of identifying interested and eligible ICs and the impact of perception of intervention on retention and likely ultimately outcome.
Significance of the results
Findings suggest preliminary support for non-pharmacological interventions to treat insomnia in ICs and emphasize the importance of matching treatment modality to the preferences and needs of ICs.
Background: Surgical site infections (SSIs) among cardiothoracic (CT) patients are associated with high rates of morbidity and mortality. Data are limited regarding SSI incidence among pediatric patients undergoing primary reparative procedures for congenital cardiac disease. Published evidence on targeted interventions to prevent pediatric CT-surgery SSI is lacking. We aimed to establish standard metrics for measuring CT-surgery SSI incidence and to implement bundled interventions for SSI prevention. Methods: A dedicated CT-surgery SSI prevention workgroup was established, consisting of hospital leadership, CT surgeons, cardiac critical care unit staff, anesthesia, perfusion, environmental services, instrument sterile processing, risk management, infection prevention and antibiotic stewardship. We created a standard definition for CT-surgery SSI and calculated retrospective SSI rates over a 24-month period (2017–2019). The outcome measured was incidence of CT-surgery SSI per 100 primary cardiac procedures with delayed ( 3 days after primary surgery) or non-delayed chest closure. The difference in proportion of SSI was reported separately for delayed closure and non-delayed closure; statistical significance was tested using a Fisher’s Exact test. We identified many potential improvement opportunities, including gaps in SSI surveillance, poor compliance with daily bathing, inconsistent perioperative antimicrobial prophylaxis, lack of controlled environment for bedside chest closures, and lapses in environmental cleaning. These issues informed the enhanced SSI prevention bundle, which included education on sterility with the operating room (OR) staff. Protocols for care of cardiac patients with delayed chest closures focused on universal daily and preoperative chlorhexidine baths. In addition, the bundle incorporated stringent environmental cleaning interventions including scheduled decluttering of patient rooms and clinical spaces, terminal cleaning of patient rooms prior to returning from the OR, and use of adjunctive ultraviolet light for the daily cleaning of operating rooms and patient rooms at discharge. Results: Surveillance definition of microbiological growth from a clinical sample obtained within 30 days of primary cardiac procedure sufficiently captured all CT-surgery SSIs. Of 551 CT-surgery procedures prior to intervention, 91 (17%) had delayed final operative closures. Prior to the intervention, 16 SSIs were identified from July 2017 – May 2019 for a rate of 2.90 per /100 procedures, and was higher among patients with delayed chest closure 6.59 per /100 procedures (6 SSIs/91 procedures) versus those with primary chest closure 2.17 per /100 procedures (10 SSIs/460 procedures; P = 0.034). Gram-positive organisms, including coagulase coagulase-negative Staphylococci, were most frequently identified as the causative organisms for SSIs. Compliance with bundled intervention, rolled out over a 2-month period, was associated with an immediate decrease in the number of SSIs for primary and delayed chest closures 6SSIs /185 procedures in the initial quarters (August – December 2019) of the post-intervention period. However, this decrease was not reflected in the overall rate (3.24 per /100 procedures) due to fewer procedures performed. Data collection to measure sustainability is ongoing. Conclusions: Bundled interventions targeting skin antisepsis and environmental cleaning may be associated with a decrease in SSIs among pediatric CT-surgery patients. Ongoing surveillance is required to determine sustainability of these interventions.
In response to advancing clinical practice guidelines regarding concussion management, service members, like athletes, complete a baseline assessment prior to participating in high-risk activities. While several studies have established test stability in athletes, no investigation to date has examined the stability of baseline assessment scores in military cadets. The objective of this study was to assess the test–retest reliability of a baseline concussion test battery in cadets at U.S. Service Academies.
Methods:
All cadets participating in the Concussion Assessment, Research, and Education (CARE) Consortium investigation completed a standard baseline battery that included memory, balance, symptom, and neurocognitive assessments. Annual baseline testing was completed during the first 3 years of the study. A two-way mixed-model analysis of variance (intraclass correlation coefficent (ICC)3,1) and Kappa statistics were used to assess the stability of the metrics at 1-year and 2-year time intervals.
Results:
ICC values for the 1-year test interval ranged from 0.28 to 0.67 and from 0.15 to 0.57 for the 2-year interval. Kappa values ranged from 0.16 to 0.21 for the 1-year interval and from 0.29 to 0.31 for the 2-year test interval. Across all measures, the observed effects were small, ranging from 0.01 to 0.44.
Conclusions:
This investigation noted less than optimal reliability for the most common concussion baseline assessments. While none of the assessments met or exceeded the accepted clinical threshold, the effect sizes were relatively small suggesting an overlap in performance from year-to-year. As such, baseline assessments beyond the initial evaluation in cadets are not essential but could aid concussion diagnosis.
Catheter-associated urinary tract infections (CAUTIs) occur frequently in pediatric inpatients, and they are associated with increased morbidity and cost. Few studies have investigated ambulatory CAUTIs, despite at-risk children utilizing home urinary catheterization. This retrospective cohort and case-control study determined incidence, risk factors, and outcomes of pediatric patients with ambulatory CAUTI.
Design:
Broad electronic queries identified potential patients with ambulatory urinary catheters, and direct chart review confirmed catheters and adjudicated whether ambulatory CAUTI occurred. CAUTI definitions included clean intermittent catheterization (CIC). Our matched case-control analysis assessed risk factors.
Setting:
Five urban, academic medical centers, part of the New York City Clinical Data Research Network.
Patients:
Potential patients were age <22 years who were seen between October 2010 and September 2015.
Results:
In total, 3,598 eligible patients were identified; 359 of these used ambulatory catheterization (representing186,616 ambulatory catheter days). Of these, 63 patients (18%) experienced 95 ambulatory CAUTIs. The overall ambulatory CAUTI incidence was 0.51 infections per 1,000 catheter days (1.35 for indwelling catheters and 0.47 for CIC; incidence rate ratio, 2.88). Patients with nonprivate medical insurance (odds ratio, 2.5; 95% confidence interval, 1.1–6.3) were significantly more likely to have ambulatory CAUTIs in bivariate models but not multivariable models. Also, 45% of ambulatory CAUTI resulted in hospitalization (median duration, 3 days); 5% resulted in intensive care admission; 47% underwent imaging; and 88% were treated with antibiotics.
Conclusions:
Pediatric ambulatory CAUTIs occur in 18% of patients with catheters; they are associated with morbidity and healthcare utilization. Ambulatory indwelling catheter CAUTI incidence exceeded national inpatient incidence. Future quality improvement research to reduce these harmful infections is warranted.
There is strong evidence that foods containing dietary fibre protect against colorectal cancer, resulting at least in part from its anti-proliferative properties. This study aimed to investigate the effects of supplementation with two non-digestible carbohydrates, resistant starch (RS) and polydextrose (PD), on crypt cell proliferative state (CCPS) in the macroscopically normal rectal mucosa of healthy individuals. We also investigated relationships between expression of regulators of apoptosis and of the cell cycle on markers of CCPS. Seventy-five healthy participants were supplemented with RS and/or PD or placebo for 50 d in a 2 × 2 factorial design in a randomised, double-blind, placebo-controlled trial (the Dietary Intervention, Stem cells and Colorectal Cancer (DISC) Study). CCPS was assessed, and the expression of regulators of the cell cycle and of apoptosis was measured by quantitative PCR in rectal mucosal biopsies. SCFA concentrations were quantified in faecal samples collected pre- and post-intervention. Supplementation with RS increased the total number of mitotic cells within the crypt by 60 % (P = 0·001) compared with placebo. This effect was limited to older participants (aged ≥50 years). No other differences were observed for the treatments with PD or RS as compared with their respective controls. PD did not influence any of the measured variables. RS, however, increased cell proliferation in the crypts of the macroscopically-normal rectum of older adults. Our findings suggest that the effects of RS on CCPS are not only dose, type of RS and health status-specific but are also influenced by age.
Carbapenem-resistant Enterobacterales (CRE) are common causes of healthcare-associated infections and are often multidrug resistant with limited therapeutic options. Additionally, CRE can spread within and between healthcare facilities, amplifying potential harms.
Objective:
To better understand the burden, risk factors, and source of acquisition of carbapenemase genes in clinical Escherichia coli and Klebsiella spp isolates from patients in Washington to guide prevention efforts.
Design:
Multicenter prospective surveillance study.
Methods:
Escherichia coli and Klebsiella spp isolates meeting the Washington state CRE surveillance case definition were solicited from clinical laboratories and tested at Washington Public Health Laboratories using polymerase chain reaction (PCR) for the 5 most common carbapenemase genes: blaKPC, blaNDM, blaIMP, blaVIM, and blaOXA-48. Case patients positive by PCR were investigated by the public health department.
Results:
From October 2012 through December 2017, 363 carbapenem-resistant E. coli and Klebsiella spp isolates were tested. Overall, 45 of 115 carbapenem-resistant K. pneumoniae (39%), 1 of 8 K. oxytoca (12.5%), and 28 of 239 carbapenem-resistant E. coli (11.7%) were carbapenemase positive. Of 74 carbapenemase-positive isolates, blaKPC was most common (47%), followed by blaNDM (30%), blaOXA-48 (22%), and blaIMP (1%). Although all cases had healthcare exposure, blaKPC acquisition was associated with US health care, whereas non-blaKPC acquisition was associated with international health care or travel.
Conclusions:
We report that blaKPC, the most prevalent carbapenemase in the United States, accounts for nearly half of carbapenemase cases in Washington state and that most KPC-cases are likely acquired through in-state health care.
The Apolipoprotein (APOE) ε4 allele increases the risk for mild cognitive impairment (MCI) and dementia, but not all carriers develop MCI/dementia. The purpose of this exploratory study was to determine if early and subtle preclinical signs of cognitive dysfunction and medial temporal lobe atrophy are observed in cognitively intact ε4 carriers who subsequently develop MCI.
Methods:
Twenty-nine healthy, cognitively intact ε4 carriers (ε3/ε4 heterozygotes; ages 65–85) underwent neuropsychological testing and MRI-based measurements of medial temporal volumes over a 5-year follow-up interval; data were converted to z-scores based on a non-carrier group consisting of 17 ε3/ε3 homozygotes.
Results:
At follow-up, 11 ε4 carriers (38%) converted to a diagnosis of MCI. At study entry, the MCI converters had significantly lower scores on the Mini-Mental State Examination, Rey Auditory Verbal Learning Test (RAVLT) Trials 1–5, and RAVLT Immediate Recall compared to non-converters. MCI converters also had smaller MRI volumes in the left subiculum than non-converters. Follow-up logistic regressions revealed that left subiculum volumes and RAVLT Trials 1–5 scores were significant predictors of MCI conversion.
Conclusions:
Results from this exploratory study suggest that ε4 carriers who convert to MCI exhibit subtle cognitive and volumetric differences years prior to diagnosis.