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result(s) for
"Cyr, Derek"
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COVID-19 prevention is shaped by polysocial risk: A cross-sectional study of vaccination and testing disparities in underserved populations
by
Bursac, Zoran
,
Perreira, Krista M.
,
Fonseca, Haley R.
in
Addictive behaviors
,
Adolescent
,
Adult
2025
Understanding disparities in COVID-19 preventive efforts among underserved populations requires a holistic approach that considers multiple social determinants of health (SDOH). While disparities in individual COVID-19 risk factors are well-documented, the cumulative impact of these factors on vaccine uptake and testing remains insufficiently quantified. This study applies a polysocial risk framework to assess the combined influence of geo-demographic, economic, and health-related factors on COVID-19 vaccination and testing. Using cross-sectional data from 9,758 participants enrolled in the NIH Rapid Acceleration of Diagnostics – Underserved Populations (RADx-UP) program (February 2020–April 2023), we analyzed associations between polysocial risk and preventive behaviors using multivariable generalized estimating equations (GEE). Overall, 72.5% of participants reported COVID-19 vaccination, and 82.1% reported testing. However, disparities were evident across polysocial risk profiles. Individuals experiencing intersecting geo-demographic (Non-Hispanic Black, age 45, Southern residence), economic (low education, unemployment, financial hardship), and health-related risk factors (substance use, low CVD risk, no flu vaccination) were 43−48 percentage points less likely to be vaccinated compared to groups with higher adoption (p < 0.001). Testing disparities were narrower but remained significant, with differences ranging from 2 to 27 percentage points depending on the specific polysocial risk profiles. The findings underscore the utility of polysocial risk modeling as a predictive tool for identifying populations at highest risk of disengagement from preventive care, informing targeted precision public health interventions. Beyond COVID-19, this approach has broader applicability for understanding disparities in chronic disease prevention, cancer screening, maternal and child health, and health-related social needs (HRSN) interventions. Integrating polysocial risk assessments into clinical and public health settings can enhance data-driven strategies to improve population health outcomes.
Journal Article
Relation of Risk of Stroke in Patients With Atrial Fibrillation to Body Mass Index (from Patients Treated With Rivaroxaban and Warfarin in the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation Trial)
by
Fox, Keith A.A.
,
Becker, Richard C.
,
Balla, Somasekhara R.
in
Administration, Oral
,
Aged
,
Anticoagulants
2017
We investigated stroke outcomes in normal weight (body mass index [BMI] 18.50 to 24.99 kg/m2), overweight (BMI 25.00 to 29.99 kg/m2), and obese (BMI ≥30 kg/m2) patients with atrial fibrillation treated with rivaroxaban and warfarin. We compared the incidence of stroke and systemic embolic events as well as bleeding events in normal weight (n = 3,289), overweight (n = 5,535), and obese (n = 5,206) patients in a post hoc analysis of the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation trial. Stroke and systemic embolic event rates per 100 patient-years were 2.93 in the normal weight group (reference group), 2.28 in the overweight group (adjusted hazard ratio [HR] 0.81, 95% CI 0.66 to 0.99, p = 0.04) and 1.88 in the obese group (adjusted HR 0.69, 95% CI 0.55 to 0.86, p <0.001). The risk of stroke was statistically significantly lower for obese patients with BMI ≥35 than that for normal weight patients in both the rivaroxaban and warfarin groups (rivaroxaban: HR 0.62, 95% CI 0.40 to 0.96, p = 0.033; warfarin: HR 0.48, 95% CI 0.31 to 0.74, p <0.001). In conclusion, in patients with atrial fibrillation treated with anticoagulant therapy, increased BMI was associated with decreased stroke risk. Warfarin and the novel anticoagulant rivaroxaban are effective in stroke prevention in all subgroups of obese patients.
Journal Article
Exposure to Mitochondrial Genotoxins and Dopaminergic Neurodegeneration in Caenorhabditis elegans
by
McKeever, Madeline G.
,
Ryde, Ian T.
,
Cyr, Derek D.
in
Adrenergic Agents - toxicity
,
Aflatoxins
,
Animals
2014
Neurodegeneration has been correlated with mitochondrial DNA (mtDNA) damage and exposure to environmental toxins, but causation is unclear. We investigated the ability of several known environmental genotoxins and neurotoxins to cause mtDNA damage, mtDNA depletion, and neurodegeneration in Caenorhabditis elegans. We found that paraquat, cadmium chloride and aflatoxin B1 caused more mitochondrial than nuclear DNA damage, and paraquat and aflatoxin B1 also caused dopaminergic neurodegeneration. 6-hydroxydopamine (6-OHDA) caused similar levels of mitochondrial and nuclear DNA damage. To further test whether the neurodegeneration could be attributed to the observed mtDNA damage, C. elegans were exposed to repeated low-dose ultraviolet C radiation (UVC) that resulted in persistent mtDNA damage; this exposure also resulted in dopaminergic neurodegeneration. Damage to GABAergic neurons and pharyngeal muscle cells was not detected. We also found that fasting at the first larval stage was protective in dopaminergic neurons against 6-OHDA-induced neurodegeneration. Finally, we found that dopaminergic neurons in C. elegans are capable of regeneration after laser surgery. Our findings are consistent with a causal role for mitochondrial DNA damage in neurodegeneration, but also support non mtDNA-mediated mechanisms.
Journal Article
Human genetic variation in GLS2 is associated with development of complicated Staphylococcus aureus bacteremia
2018
The role of host genetic variation in the development of complicated Staphylococcus aureus bacteremia (SAB) is poorly understood. We used whole exome sequencing (WES) to examine the cumulative effect of coding variants in each gene on risk of complicated SAB in a discovery sample of 168 SAB cases (84 complicated and 84 uncomplicated, frequency matched by age, sex, and bacterial clonal complex [CC]), and then evaluated the most significantly associated genes in a replication sample of 240 SAB cases (122 complicated and 118 uncomplicated, frequency matched for age, sex, and CC) using targeted sequence capture. In the discovery sample, gene-based analysis using the SKAT-O program identified 334 genes associated with complicated SAB at p<3.5 x 10-3. These, along with eight biologically relevant candidate genes were examined in the replication sample. Gene-based analysis of the 342 genes in the replication sample using SKAT-O identified one gene, GLS2, significantly associated with complicated SAB (p = 1.2 x 10-4) after Bonferroni correction. In Firth-bias corrected logistic regression analysis of individual variants, the strongest association across all 10,931 variants in the replication sample was with rs2657878 in GLS2 (p = 5 x 10-4). This variant is strongly correlated with a missense variant (rs2657879, p = 4.4 x 10-3) in which the minor allele (associated here with complicated SAB) has been previously associated with lower plasma concentration of glutamine. In a microarray-based gene-expression analysis, individuals with SAB exhibited significantly lower expression levels of GLS2 than healthy controls. Similarly, Gls2 expression is lower in response to S. aureus exposure in mouse RAW 264.7 macrophage cells. Compared to wild-type cells, RAW 264.7 cells with Gls2 silenced by CRISPR-Cas9 genome editing have decreased IL1-β transcription and increased nitric oxide production after S. aureus exposure. GLS2 is an interesting candidate gene for complicated SAB due to its role in regulating glutamine metabolism, a key factor in leukocyte activation.
Journal Article
Structural abnormalities and effects of sacubitril/valsartan in patients with mildly reduced or preserved ejection fraction and worsening heart failure: The PARAGLIDE-HF trial
by
Solomon, Scott D.
,
Hernandez, Adrian F.
,
Mentz, Robert J.
in
Abnormalities
,
Aged
,
Aminobutyrates - administration & dosage
2025
•While structural abnormalities are common, approximately three-quarters of the PARAGLIDE-HF population exhibited such abnormalities, as evidenced by left ventricular hypertrophy (LVH) and left atrial enlargement (LAE).•There was no difference in either baseline NT-proBNP or changes in NT-proBNP over time, nor was there a difference in the time to the first cardiovascular composite event across varying degrees of structural abnormalities.•A greater reduction in NT-proBNP with sacubitril/valsartan vs valsartan was consistent across all structural abnormality groups.•There was no significant interaction between treatment and degree of structural abnormalities for other efficacy endpoints, but patients with both LVH and LAE had significantly higher odds of hyperkalemia with sacubitril/valsartan.
PARAGLIDE-HF showed significantly greater reduction in NT-proBNP in patients with LVEF>40% and worsening HF with sacubitril/valsartan (sac/val) vs valsartan (val). The impact of structural abnormalities on the effects of sac/val in this context is unknown. This study aimed to evaluate the impact of left ventricular hypertrophy (LVH) and left atrial enlargement (LAE) on sac/val in patients with LVEF>40% and worsening HF.
PARAGLIDE-HF patients were classified into 3 groups according the degree of structural abnormalities using LVH and LAE. The primary endpoint was time-averaged proportional change in NT-proBNP from baseline to Weeks 4 and 8. Secondary endpoints were recurrent cardiovascular composite events (HF hospitalizations, urgent HF visits, cardiovascular death) and adverse events (symptomatic hypotension, hyperkalemia, worsening renal function).
Of 454 (97.4%) patients with LVH and LAE data, 157 (34.5%) had both LVH and LAE, 178 (39.2%) had either LVH or LAE, and 119 (26.2%) had neither LVH nor LAE. Greater reduction in NT-proBNP with sac/val vs val was consistent across groups (P interaction = 0.705). There was no significant interaction between treatment and degree of structural abnormalities for other efficacy endpoints. Patients with both LVH and LAE had significantly higher odds of hyperkalemia with sac/val (OR 2.41, P interaction = 0.024).
Patients with LVEF>40% and recent WHF had greater reduction in NT-proBNP with sac/val vs val, regardless of the degree of structural abnormalities. There was no difference in the effects of sac/val on efficacy endpoints across structural abnormality group. Patients with both LVH and LAE had higher odds for hyperkalemia with sac/val.
Prevalence and impact of structural abnormalities on the effects of sacubitril/valsartan in patients with LVEF >40% and a recent worsening heart failure event [Display omitted]
Journal Article
Win Ratio Analyses Using a Modified Hierarchical Composite Outcome: Insights From PARAGLIDE-HF
by
Hernandez, Adrian F.
,
Velazquez, Eric J.
,
Solomon, Scott D.
in
Aged
,
Aminobutyrates - therapeutic use
,
Angiotensin Receptor Antagonists - therapeutic use
2025
The win ratio (WR) is an emerging alternative for reporting composite outcomes, prioritizing clinically significant events such as mortality while incorporating surrogate measures. However, its benefits should be weighed against limitations, particularly the influence of lower hierarchical outcomes. This secondary analysis of the PARAGLIDE-HF trial performed a WR sensitivity analysis using a modified hierarchical composite outcome to assess the utility of WR sensitivity analysis and the efficacy of sacubitril/valsartan versus valsartan.
PARAGLIDE-HF compared sacubitril/valsartan with valsartan in heart failure (HF) patients with ejection fraction >40% (N = 466). A hierarchical outcome in the primary analysis included cardiovascular death, HF hospitalizations, urgent HF visits, and change in N-terminal pro–B-type natriuretic peptide (NT-proBNP), with a 25% decrease considered a win. In the prespecified subgroup with ejection fraction ≤60% (N = 357), sacubitril/valsartan showed a treatment effect on the hierarchical outcome (WR, 1.46; 95% CI, 1.08-1.97). Sensitivity analyses for this subgroup included: (1) excluding NT-proBNP change, (2) substituting the 25% proportion change of NT-proBNP with 10% or 50%, and (3) including renal outcomes within the hierarchical outcome. In addition to the WR, the win odds (WO), in which 50% of the ties are allocated to both the numerator and denominator of the WR—a potentially more suitable modification of the WR that accounts for the presence of ties—were presented.
Excluding NT-proBNP (WR, 1.49; 95% CI, 1.00-2.22; WO, 1.12; 95% CI, 1.00-1.26), adjusting the NT-proBNP threshold from 25% to 10% or 50% (WR, 1.41; 95% CI, 1.06-1.89; WO, 1.27; 95% CI, 1.04-1.56 for 10%; and WR, 1.54; 95% CI, 1.11-2.12; WO, 1.25; 95% CI, 1.06-1.48 for 50%), and incorporating renal outcomes (WR, 1.44; 95% CI, 1.07-1.94; WO, 1.28; 95% CI, 1.05-1.56) consistently favored sacubitril/valsartan.
Multiple WR sensitivity analyses support a consistent treatment benefit of sacubitril/valsartan versus valsartan in patients with ejection fraction >40% to 60%. Future studies could consider prespecifying WR sensitivity analysis for comprehensive assessment of treatment effects.
PARAGLIDE-HF; ClinicalTrials.gov ID, NCT03988634 (https://clinicaltrials.gov/study/NCT03988634).
Journal Article
Gene Expression Profiles Link Respiratory Viral Infection, Platelet Response to Aspirin, and Acute Myocardial Infarction
by
Rose, Jason J.
,
Kraus, William E.
,
Woods, Christopher W.
in
Acute coronary syndromes
,
Aged
,
Aspirin
2015
Influenza infection is associated with myocardial infarction (MI), suggesting that respiratory viral infection may induce biologic pathways that contribute to MI. We tested the hypotheses that 1) a validated blood gene expression signature of respiratory viral infection (viral GES) was associated with MI and 2) respiratory viral exposure changes levels of a validated platelet gene expression signature (platelet GES) of platelet function in response to aspirin that is associated with MI.
A previously defined viral GES was projected into blood RNA data from 594 patients undergoing elective cardiac catheterization and used to classify patients as having evidence of viral infection or not and tested for association with acute MI using logistic regression. A previously defined platelet GES was projected into blood RNA data from 81 healthy subjects before and after exposure to four respiratory viruses: Respiratory Syncytial Virus (RSV) (n=20), Human Rhinovirus (HRV) (n=20), Influenza A virus subtype H1N1 (H1N1) (n=24), Influenza A Virus subtype H3N2 (H3N2) (n=17). We tested for the change in platelet GES with viral exposure using linear mixed-effects regression and by symptom status.
In the catheterization cohort, 32 patients had evidence of viral infection based upon the viral GES, of which 25% (8/32) had MI versus 12.2% (69/567) among those without evidence of viral infection (OR 2.3; CI [1.03-5.5], p=0.04). In the infection cohorts, only H1N1 exposure increased platelet GES over time (time course p-value = 1e-04).
A viral GES of non-specific, respiratory viral infection was associated with acute MI; 18% of the top 49 genes in the viral GES are involved with hemostasis and/or platelet aggregation. Separately, H1N1 exposure, but not exposure to other respiratory viruses, increased a platelet GES previously shown to be associated with MI. Together, these results highlight specific genes and pathways that link viral infection, platelet activation, and MI especially in the case of H1N1 influenza infection.
Journal Article
Electronic health record characterization and outcomes of heart failure with preserved ejection fraction
by
Rao, Vishal N.
,
Sanders, Gretchen
,
Siedentop, Harald
in
Cardiac arrhythmia
,
Cardiac catheterization
,
Clinical trials
2023
Electronic health record (EHR)-based identification of heart failure with preserved ejection fraction (HFpEF) in the clinical setting may facilitate screening for clinical trials by improving the understanding of its epidemiology and outcomes; yet, previous data have yielded variable results. We sought to characterize groups identified with HFpEF by different EHR screening strategies and their associated long-term outcomes across a large and diverse population.
We retrospectively analyzed 116,499 consecutive patients from an academic referral center who underwent echocardiography, and 9,263 patients who underwent echocardiography within 6 months of right heart catheterization (RHC), between 2008 and 2018. EHR-based screening strategies identified patients with HFpEF using 1) International Classification of Diseases (ICD)-9/10 codes, 2) H2FpEF score ≥6 and ejection fraction (EF) ≥50%, or 3) RHC wedge pressure ≥15 mmHg and EF ≥50%, when available. Primary outcomes were 1) cumulative incident heart failure hospitalization (HFH), and 2) death, over 10 years.
There were 33,461 (29%) patients who met either ICD or H2FpEF-HFpEF definition, of whom 5,310 (16%) met both criteria. Compared to ICD-HFpEF, patients with H2FpEF-HFpEF were more likely older (median age 72 vs 67), White (78% vs 64%), and had atrial fibrillation (97% vs 41%). Among those also with RHC, 6,353 (69%) patients met any HFpEF criteria, of whom only 783 (12%) satisfied all three criteria. Female sex was more common among RHC-HFpEF (55%) compared to other methods (H2FpEF-HFpEF, 47%; ICD-HFpEF, 43%). Atrial fibrillation was substantially higher among HFpEF identified by the H2FpEF score (97%) compared to other methods (49% for ICD and 47% for RHC). Across HFpEF screening methods, 10-year cumulative incidence rates for HFH was 32% to 45% for echocardiography only and 43% to 52% for echocardiography and RHC populations; 10-year risk of death was 54% to 56% for echocardiography only and 52% to 57% for echocardiography and RHC populations.
Different EHR-based HFpEF definitions identified cohorts with modest overlap and varying baseline characteristics. Yet, long-term risk for HFH and death were similarly high for cohorts identified among both populations undergoing echocardiography only or echocardiography and RHC. These data aid in identifying relevant subgroups in clinical trials of HFpEF.
Journal Article
Gene Expression-Based Classifiers Identify Staphylococcus aureus Infection in Mice and Humans
2013
Staphylococcus aureus causes a spectrum of human infection. Diagnostic delays and uncertainty lead to treatment delays and inappropriate antibiotic use. A growing literature suggests the host's inflammatory response to the pathogen represents a potential tool to improve upon current diagnostics. The hypothesis of this study is that the host responds differently to S. aureus than to E. coli infection in a quantifiable way, providing a new diagnostic avenue. This study uses Bayesian sparse factor modeling and penalized binary regression to define peripheral blood gene-expression classifiers of murine and human S. aureus infection. The murine-derived classifier distinguished S. aureus infection from healthy controls and Escherichia coli-infected mice across a range of conditions (mouse and bacterial strain, time post infection) and was validated in outbred mice (AUC>0.97). A S. aureus classifier derived from a cohort of 94 human subjects distinguished S. aureus blood stream infection (BSI) from healthy subjects (AUC 0.99) and E. coli BSI (AUC 0.84). Murine and human responses to S. aureus infection share common biological pathways, allowing the murine model to classify S. aureus BSI in humans (AUC 0.84). Both murine and human S. aureus classifiers were validated in an independent human cohort (AUC 0.95 and 0.92, respectively). The approach described here lends insight into the conserved and disparate pathways utilized by mice and humans in response to these infections. Furthermore, this study advances our understanding of S. aureus infection; the host response to it; and identifies new diagnostic and therapeutic avenues.
Journal Article
Candidate genes on murine chromosome 8 are associated with susceptibility to Staphylococcus aureus infection in mice and are involved with Staphylococcus aureus septicemia in humans
by
Sharma-Kuinkel, Batu K.
,
Woods, Christopher W.
,
Medie, Felix Mba
in
Alleles
,
Animals
,
Antigens, CD - metabolism
2017
We previously showed that chromosome 8 of A/J mice was associated with susceptibility to S. aureus infection. However, the specific genes responsible for this susceptibility are unknown. Chromosome substitution strain 8 (CSS8) mice, which have chromosome 8 from A/J but an otherwise C57BL/6J genome, were used to identify the genetic determinants of susceptibility to S. aureus on chromosome 8. Quantitative trait loci (QTL) mapping of S. aureus-infected N2 backcross mice (F1 [C8A] × C57BL/6J) identified a locus 83180780-88103009 (GRCm38/mm10) on A/J chromosome 8 that was linked to S. aureus susceptibility. All genes on the QTL (n~ 102) were further analyzed by three different strategies: 1) different expression in susceptible (A/J) and resistant (C57BL/6J) mice only in response to S. aureus, 2) consistently different expression in both uninfected and infected states between the two strains, and 3) damaging non-synonymous SNPs in either strain. Eleven candidate genes from the QTL region were significantly differently expressed in patients with S. aureus infection vs healthy human subjects. Four of these 11 genes also exhibited significantly different expression in S. aureus-challenged human neutrophils: Ier2, Crif1, Cd97 and Lyl1. CD97 ligand binding was evaluated within peritoneal neutrophils from A/J and C57BL/6J. CD97 from A/J had stronger CD55 but weaker integrin α5β1 ligand binding as compared with C57BL/6J. Because CD55/CD97 binding regulates immune cell activation and cytokine production, and integrin α5β1 is a membrane receptor for fibronectin, which is also bound by S. aureus, strain-specific differences could contribute to susceptibility to S. aureus. Down-regulation of Crif1 with siRNA was associated with increased host cell apoptosis among both naïve and S. aureus-infected bone marrow-derived macrophages. Specific genes in A/J chromosome 8, including Cd97 and Crif1, may play important roles in host defense against S. aureus.
Journal Article