Faculty Bibliography

IMPORTANCE/OBJECTIVE:Prior studies have demonstrated the effectiveness of COVID-19 vaccines in children and adolescents. However, the benefits of vaccination in these age groups with prior infection remain underexplored. OBJECTIVE:To evaluate the effectiveness of COVID-19 vaccination in preventing reinfection with various Omicron subvariants (BA.1/2, BA.4/5, XBB, and later) among 5- to 17-year-olds with prior SARS-CoV-2 infection. DESIGN/METHODS:A target trial emulation through nested designs with distinct study periods. SETTING/METHODS:The study utilized data from the Research COVID to Enhance Recovery (RECOVER) initiative, a national electronic health record (EHR) database comprising 37 U.S. children's hospitals and health institutions. PARTICIPANTS/METHODS:Individuals aged 5-17 years with a documented history of SARS-CoV-2 infection prior to the study start date during a specific variant-dominant period (Delta, BA.1/2, or BA.4/5) who received a subsequent dose of COVID-19 vaccine during the study periods were compared with those with a documented history of infection who did not receive SARS-CoV-2 vaccine during the study period. Those infected within the Delta-Omicron composite period (December 1, 2021, to December 31, 2021) were excluded. The study period was from January 1, 2022, to August 30, 2023, and focused on adolescents aged 12 to 17 years and children aged 5 to 11 years. EXPOSURES/METHODS:At least received one COVID-19 vaccination during the study period vs. no receipt of any COVID-19 vaccine during the study period. MAIN OUTCOMES AND MEASURES/METHODS:The primary outcome is documented SARS-CoV-2 reinfection during the study period (both asymptomatic and symptomatic cases). The effectiveness of the COVID-19 vaccine was estimated as (1- hazard ratio) *100%, with confounders adjusted by a combination of propensity score matching and exact matching. RESULTS:The study analyzed 87,573 participants during the BA.1/2 period, 229,326 during the BA.4/5 period, and 282,981 during the XBB or later period. Among vaccinated individuals, significant protection was observed during the BA.1/2 period, with effectiveness rates of 62% (95% CI: 38%-77%) for children and 65% (95% CI: 32%-81%) for adolescents. During the BA.4/5 period, vaccine effectiveness was 57% (95% CI: 25%-76%) for children, but not statistically significant for adolescents (36%, 95% CI: -16%-65%). For the XBB period, no significant protection was observed in either group, with effectiveness rates of 22% (95% CI: -36%-56%) in children and 34% (95% CI: -10%-61%) in adolescents. CONCLUSIONS AND RELEVANCE/CONCLUSIONS:COVID-19 vaccination provides significant protection against reinfection for children and adolescents with prior infections during the early and mid-Omicron periods. This study also highlights the importance of addressing low vaccination rates in pediatric populations to enhance protection against emerging variants.

OBJECTIVE:Seizures can impact cognition both acutely and chronically. However, among those without significant comorbidities and broadly average cognition at epilepsy onset, the relationship between cognitive function at the time of diagnosis and long-term seizure control has been relatively unexplored. This analysis investigated associations between participant characteristics including specific aspects of cognitive performance at the time of focal epilepsy diagnosis and antiseizure medication (ASM) treatment resistance. METHODS:This was a secondary analysis of Human Epilepsy Project (HEP) data, which enrolled people with newly diagnosed focal epilepsy and broadly average cognition (estimated IQ ≥ 70) from June 29, 2012, to September 1, 2019. Participants analyzed in this study were between 18 and 60 years old, and scored within an acceptable range (i.e., Standard Score of ≥80) on measures estimating premorbid cognitive ability were offered the Cogstate Brief Battery (CBB). Participant characteristics were analyzed, including the presence of any anxiety disorders or depression, and summary CBB scores. HEP participants who were classified by the study as treatment resistant if they had experienced failure to achieve seizure freedom after two adequate trials of ASMs. Treatment resistance was modeled using multiple logistic regression to assess for independent associations between attention and working memory after correcting for the presence of the other potentially explanatory variables. RESULTS:200 HEP participants had comprehensive enrollment records including CBB results and complete seizure outcome data for analysis in this study. After correcting for potentially confounding variables, there were no independent associations between cognitive measures on the CBB at the time of enrollment and subsequent development of ASM treatment resistance. Specifically, z-scores for reaction time on the CBB (an average of the CBB Identification and Detection tests) were not associated with treatment resistance (p = 0.51) and z-scores for memory performance (an average of the CBB One Card Learning test and One Back tests) were not associated with treatment resistance (p = 0.24). There were no significant independent associations between age or the presence of depression or anxiety disorders at the time of CBB testing and treatment resistance. However, there was an independent association between employment status and treatment resistance, with those who were employed or students (>18 years old) at the time of enrollment and CBB testing having 0.35 times lower odds of treatment resistance (95 %CI 0.15-0.81, p = 0.01). SIGNIFICANCE/CONCLUSIONS:The findings from this study suggest that in otherwise healthy people with new onset focal epilepsy who have broadly average intelligence, attention and working memory as measured by the CBB at the time of diagnosis is not associated with treatment resistance. Although performance on cognitive testing at epilepsy onset may not be predictive of risk of treatment resistance in this population, other individual characteristics such as employment status at the time of diagnosis may be indirect markers of long-term seizure outcomes and require further investigation.

Fatigue is a common and often debilitating feature of multiple sclerosis (MS) that lacks reliably effective treatment options for most patients. Transcranial direct current stimulation (tDCS), a safe and well-tolerated type of noninvasive brain stimulation, is a low-cost and home-based approach with the potential to reduce fatigue in MS. We conducted a double-blind, sham-controlled, randomized clinical trial to compare active vs. low-dose (sham) tDCS paired with computer-based cognitive training, delivered as a home-based intervention, to reduce MS-related fatigue. Participants with MS-related fatigue, but without depression, were stratified by neurologic disability using the Extended Disability Status Scale (EDSS) and randomized to complete 30 daily sessions over six weeks of either active or sham tDCS paired with online cognitive training (BrainHQ). The primary outcome was the change in PROMIS Fatigue score from baseline to the end of the intervention. A total of 117 participants were randomized, with 92% completing all treatment sessions. Both groups showed significant reductions in fatigue, with no significant difference between them. This suggests that tDCS does not provide any additional benefit over cognitive training alone in reducing fatigue, but confirms the feasibility and tolerance of this home-based intervention.

BACKGROUND:Hemorrhagic stroke survivors may have cognitive impairment. We sought to identify preadmission and admission factors associated with cognitive impairment after hemorrhagic stroke. DESIGN/METHODS:Patients with nontraumatic intracerebral or subarachnoid hemorrhage (ICH or SAH) were assessed 3-months post-bleed using the Quality of Life in Neurological Disorders (Neuro-QoL) Cognitive Function short form. Univariate and multivariate analysis were used to evaluate the relationship between poor cognition (Neuro-QoL t-score ≤50) and preadmission and admission factors. RESULTS:Of 101 patients (62 ICH and 39 SAH), 51 (50 %) had poor cognition 3-months post-bleed. On univariate analysis, poor cognition was associated with (p < 0.05): age [66.0 years (52.0-77.0) vs. 54.5 years (40.8-66.3)]; private insurance (37.3 % vs. 74.0 %); BMI > 30 (13.7 % vs. 34.0 %); and admission mRS score > 0 (41.2 % vs. 14.0 %), NIHSS score [8.0 (2.0-17.0) vs. 0.5 (0.0-4.0)], and APACHE II score [16.0 (11.0-19.0) vs. 9.0 (6.0-14.3)]. On multivariate analysis, poor cognition was associated with mRS score > 0 [OR 4.97 (1.30-19.0), p = 0.019], NIHSS score [OR 1.14 (1.02-1.28), p = 0.026], private insurance [OR 0.21 (0.06-0.76), p = 0.017] and BMI > 30 [OR 0.13 (0.03-0.56), p = 0.006]. CONCLUSIONS:Cognitive impairment after hemorrhagic stroke is less common in patients with BMI > 30 and private insurance. Heightened surveillance for non-obese patients without private insurance is suggested. Additional investigation into the relationship between cognition and both BMI and insurance type is needed.

IMPORTANCE/UNASSIGNED:The profile of gastrointestinal (GI) tract outcomes associated with the postacute and chronic phases of COVID-19 in children and adolescents remains unclear. OBJECTIVE/UNASSIGNED:To investigate the risks of GI tract symptoms and disorders during the postacute (28-179 days after documented SARS-CoV-2 infection) and the chronic (180-729 days after documented SARS-CoV-2 infection) phases of COVID-19 in the pediatric population. DESIGN, SETTING, AND PARTICIPANTS/UNASSIGNED:This retrospective cohort study was performed from March 1, 2020, to September 1, 2023, at 29 US health care institutions. Participants included pediatric patients 18 years or younger with at least 6 months of follow-up. Data analysis was conducted from November 1, 2023, to February 29, 2024. EXPOSURES/UNASSIGNED:Presence or absence of documented SARS-CoV-2 infection. Documented SARS-CoV-2 infection included positive results of polymerase chain reaction analysis, serological tests, or antigen tests for SARS-CoV-2 or diagnosis codes for COVID-19 and postacute sequelae of SARS-CoV-2. MAIN OUTCOMES AND MEASURES/UNASSIGNED:GI tract symptoms and disorders were identified by diagnostic codes in the postacute and chronic phases following documented SARS-CoV-2 infection. The adjusted risk ratios (ARRs) and 95% CI were determined using a stratified Poisson regression model, with strata computed based on the propensity score. RESULTS/UNASSIGNED:The cohort consisted of 1 576 933 pediatric patients (mean [SD] age, 7.3 [5.7] years; 820 315 [52.0%] male). Of these, 413 455 patients had documented SARS-CoV-2 infection and 1 163 478 did not; 157 800 (13.6%) of those without documented SARS-CoV-2 infection had a complex chronic condition per the Pediatric Medical Complexity Algorithm. Patients with a documented SARS-CoV-2 infection had an increased risk of developing at least 1 GI tract symptom or disorder in both the postacute (8.64% vs 6.85%; ARR, 1.25; 95% CI, 1.24-1.27) and chronic (12.60% vs 9.47%; ARR, 1.28; 95% CI, 1.26-1.30) phases compared with patients without a documented infection. Specifically, the risk of abdominal pain was higher in COVID-19-positive patients during the postacute (2.54% vs 2.06%; ARR, 1.14; 95% CI, 1.11-1.17) and chronic (4.57% vs 3.40%; ARR, 1.24; 95% CI, 1.22-1.27) phases. CONCLUSIONS AND RELEVANCE/UNASSIGNED:In this cohort study, the increased risk of GI tract symptoms and disorders was associated with the documented SARS-CoV-2 infection in children or adolescents during the postacute or chronic phase. Clinicians should note that lingering GI tract symptoms may be more common in children after documented SARS-CoV-2 infection than in those without documented infection.

Cancer of unknown primary (CUP) constitutes between 2% and 5% of human malignancies and is among the most common causes of cancer death in the United States. Brain metastases are often the first clinical presentation of CUP; despite extensive pathological and imaging studies, 20%-45% of CUP are never assigned a primary site. DNA methylation array profiling is a reliable method for tumor classification but tumor-type-specific classifier development requires many reference samples. This is difficult to accomplish for CUP as many cases are never assigned a specific diagnosis. Recent studies identified subsets of methylation quantitative trait loci (mQTLs) unique to specific organs, which could help increase classifier accuracy while requiring fewer samples. We performed a retrospective genome-wide methylation analysis of 759 carcinoma samples from formalin-fixed paraffin-embedded tissue samples using Illumina EPIC array. Utilizing mQTL specific for breast, lung, ovarian/gynecologic, colon, kidney, or testis (BLOCKT) (185k total probes), we developed a deep learning-based methylation classifier that achieved 93.12% average accuracy and 93.04% average F1-score across a 10-fold validation for BLOCKT organs. Our findings indicate that our organ-based DNA methylation classifier can assist pathologists in identifying the site of origin, providing oncologists insight on a diagnosis to administer appropriate therapy, improving patient outcomes.

The adoption of large language models (LLMs) in healthcare demands a careful analysis of their potential to spread false medical knowledge. Because LLMs ingest massive volumes of data from the open Internet during training, they are potentially exposed to unverified medical knowledge that may include deliberately planted misinformation. Here, we perform a threat assessment that simulates a data-poisoning attack against The Pile, a popular dataset used for LLM development. We find that replacement of just 0.001% of training tokens with medical misinformation results in harmful models more likely to propagate medical errors. Furthermore, we discover that corrupted models match the performance of their corruption-free counterparts on open-source benchmarks routinely used to evaluate medical LLMs. Using biomedical knowledge graphs to screen medical LLM outputs, we propose a harm mitigation strategy that captures 91.9% of harmful content (F1 = 85.7%). Our algorithm provides a unique method to validate stochastically generated LLM outputs against hard-coded relationships in knowledge graphs. In view of current calls for improved data provenance and transparent LLM development, we hope to raise awareness of emergent risks from LLMs trained indiscriminately on web-scraped data, particularly in healthcare where misinformation can potentially compromise patient safety.

BACKGROUND:There is practice heterogeneity in the use, type, and duration of prophylactic antiseizure medications (ASM) in patients hospitalized with acute nontraumatic intracerebral hemorrhage (ICH). METHODS:We conducted a systematic review and meta-analysis assessing ASM primary prophylaxis in adults hospitalized with acute nontraumatic ICH. The following population, intervention, comparison, and outcome (PICO) questions were assessed: (1) Should ASM versus no ASM be used in patients with acute ICH with no history of clinical or electrographic seizures? (2) If an ASM is used, should levetiracetam (LEV) or phenytoin/fosphenytoin (PHT/fPHT) be preferentially used? and (3) If an ASM is used, should a long (> 7 days) versus short (≤ 7 days) duration of prophylaxis be used? The main outcomes assessed were early seizure (≤ 14 days), late seizures (> 14 days), adverse events, mortality, and functional and cognitive outcomes. We used Grading of Recommendations Assessment, Development, and Evaluation methodology to generate recommendations. RESULTS:The initial literature search yielded 1,988 articles, and 15 formed the basis of the recommendations. PICO 1: although there was no significant impact of ASM on the outcomes of early or late seizure or mortality, meta-analyses demonstrated increased adverse events and higher relative risk of poor functional outcomes at 90 days with prophylactic ASM use. PICO 2: we did not detect any significant positive or negative effect of PHT/fPHT compared to LEV for early seizures or adverse events, although point estimates tended to favor LEV. PICO 3: based on one decision analysis, quality-adjusted life-years were increased with a shorter duration of ASM prophylaxis. CONCLUSIONS:We suggest avoidance of prophylactic ASM in hospitalized adult patients with acute nontraumatic ICH (weak recommendation, very low quality of evidence). If used, we suggest LEV over PHT/fPHT (weak recommendation, very low quality of evidence) for a short duration (≤ 7 days; weak recommendation, very low quality of evidence).

The α-synuclein seed amplification assay (αSyn-SAA) sensitively detects Lewy pathology, the amyloid state of α-synuclein, in the cerebrospinal fluid (CSF) of patients with Parkinson's disease (PD). The αSyn-SAA harnesses the physics of seeding, whereby a superconcentrated solution of recombinant α-synuclein lowers the thermodynamic threshold (nucleation barrier) for aggregated α-synuclein to act as a nucleation catalyst ("seed") to trigger the precipitation (nucleation) of monomeric α-synuclein into pathology. This laboratory setup increases the signal for identifying a catalyst if one is present in the tissue examined. The result is binary: positive, meaning precipitation occurred, and a catalyst is present, or negative, meaning no precipitation, therefore no catalyst. Since protein precipitation via seeding can only occur at a concentration many-fold higher than the human brain, laboratory-elicited seeding does not mean human brain seeding. We suggest that a positive αSyn-SAA reveals the presence of pathological α-synuclein but not the underlying etiology for the precipitation of monomeric α-synuclein into its pathological form. Thus, a positive αSyn-SAA supports a clinical diagnosis of PD but cannot inform disease pathogenesis, ascertain severity, predict the rate of progression, define biology or biological subtypes, or monitor treatment response.