34 results on '"Kwon, Y."'
Search Results
2. Habitat and Vegetation Variables Are Not Enough When Predicting Tick Populations in the Southeastern United States.
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Trout Fryxell, R. T., Moore, J. E., Collins, M. D., Kwon, Y., Jean-Philippe, S. R., Schaeffer, S. M., Odoi, A., Kennedy, M., and Houston, A. E.
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HABITATS ,TICK-borne diseases ,EHRLICHIOSIS ,PLANT species ,PLANT-soil relationships - Abstract
Two tick-borne diseases with expanding case and vector distributions are ehrlichiosis (transmitted by Amblyomma americanum) and rickettiosis (transmitted by A. maculatum and Dermacentor variabilis). There is a critical need to identify the specific habitats where each of these species is likely to be encountered to classify and pinpoint risk areas. Consequently, an in-depth tick prevalence study was conducted on the dominant ticks in the southeast. Vegetation, soil, and remote sensing data were used to test the hypothesis that habitat and vegetation variables can predict tick abundances. No variables were significant predictors of A. americanum adult and nymph tick abundance, and no clustering was evident because this species was found throughout the study area. For A. maculatum adult tick abundance was predicted by NDVI and by the interaction between habitat type and plant diversity; two significant population clusters were identified in a heterogeneous area suitable for quail habitat. For D. variabilis no environmental variables were significant predictors of adult abundance; however, D. variabilis collections clustered in three significant areas best described as agriculture areas with defined edges. This study identified few landscape and vegetation variables associated with tick presence. While some variables were significantly associated with tick populations, the amount of explained variation was not useful for predicting reliably where ticks occur; consequently, additional research that includes multiple sampling seasons and locations throughout the southeast are warranted. This low amount of explained variation may also be due to the use of hosts for dispersal, and potentially to other abiotic and biotic variables. Host species play a large role in the establishment, maintenance, and dispersal of a tick species, as well as the maintenance of disease cycles, dispersal to new areas, and identification of risk areas. [ABSTRACT FROM AUTHOR]
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- 2015
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3. A Comparison of Korean Cellulose Insulation with Cellulose Insulation Manufactured in the United States of America.
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Kwon, Y. C. and Yarbrough, D. W.
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CELLULOSE insulation , *INSULATING materials , *CONSTRUCTION materials , *INSULATING materials industry - Abstract
Thermal resistivity data are reported for loose-fill cellulose manufactured in Korea and the United States over the temperature range 40 to 100°F. A representative thickness of 1.1 in. for thermal test specimens was determined for cellulose insulation in the density range that was studied. Measurements for insulations with known amounts of fire retardant chemical showed a negligible effect of the fire retardant on the thermal resistivity of the insulation. The test data show that the U.S.-made loose-fill cellulose that was studied had a 5% greater thermal resistivity than the Korean-made product. This difference in thermal resistivity could be due to differences in the re-cycled paper being used in the two countries to produce cellulose insulation [ABSTRACT FROM AUTHOR]
- Published
- 2004
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4. 981PEconomic and humanistic burden of cervical cancer in the United States.
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Nwankwo, C, Shah, R, Kwon, Y, and Corman, S
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CERVICAL cancer , *URBAN hospitals , *TUMOR classification - Published
- 2018
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5. Impact of the Affordable Care Act on access to accredited facilities for cancer treatment.
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Sabik LM, Kwon Y, Drake C, Yabes J, Bhattacharya M, Sun Z, Bradley CJ, and Jacobs BL
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- Humans, Male, Female, Middle Aged, Pennsylvania, United States, Adult, Patient Protection and Affordable Care Act, Health Services Accessibility statistics & numerical data, Neoplasms therapy, Insurance Coverage statistics & numerical data, Cancer Care Facilities statistics & numerical data
- Abstract
Objective: To examine differential changes in receipt of surgery at National Cancer Institute (NCI)-designated comprehensive cancer centers (NCI-CCC) and Commission on Cancer (CoC) accredited hospitals for patients with cancer more likely to be newly eligible for coverage under Affordable Care Act (ACA) insurance expansions, relative to those less likely to have been impacted by the ACA., Data Sources and Study Setting: Pennsylvania Cancer Registry (PCR) for 2010-2019 linked with discharge records from the Pennsylvania Health Care Cost Containment Council (PHC4)., Study Design: Outcomes include whether cancer surgery was performed at an NCI-CCC or a CoC-accredited hospital. We conducted a difference-in-differences analysis, estimating linear probability models for each outcome that control for residence in a county with above median county-level pre-ACA uninsurance and the interaction between county-level baseline uninsurance and cancer treatment post-ACA to capture differential changes in access between those more and less likely to become newly eligible for insurance coverage (based on area-level proxy). All models control for age, sex, race and ethnicity, cancer site and stage, census-tract level urban/rural residence, Area Deprivation Index, and year- and county-fixed effects., Data Collection/extraction Methods: We identified adults aged 26-64 in PCR with prostate, lung, or colorectal cancer who received cancer-directed surgery and had a corresponding surgery discharge record in PHC4., Principal Findings: We observe a differential increase in receiving care at an NCI-CCC of 6.2 percentage points (95% CI: 2.6-9.8; baseline mean = 9.8%) among patients in high baseline uninsurance areas (p = 0.001). Our estimate of the differential change in care at the larger set of CoC hospitals is positive (3.9 percentage points [95% CI: -0.5-8.2; baseline mean = 73.7%]) but not statistically significant (p = 0.079)., Conclusions: Our findings suggest that insurance expansions under the ACA were associated with increased access to NCI-CCCs., (© 2024 The Authors. Health Services Research published by Wiley Periodicals LLC on behalf of Health Research and Educational Trust.)
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- 2024
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6. Does the Surgical Approach Affect the Incidence of Post-Hepatectomy Liver Failure in Cirrhotic Patients? An Analysis of the NSQIP Database.
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Jehan FS, Ganguli S, Hase NE, Seth A, Kwon Y, Hemming AW, and Aziz H
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- Humans, Male, Female, Middle Aged, Incidence, Databases, Factual, Aged, Retrospective Studies, United States epidemiology, Minimally Invasive Surgical Procedures, Hepatectomy adverse effects, Liver Cirrhosis complications, Liver Cirrhosis surgery, Liver Failure etiology, Liver Failure epidemiology, Propensity Score, Postoperative Complications epidemiology, Postoperative Complications etiology
- Abstract
Background: The association between surgical approach and post-hepatectomy liver failure (PHLF) in cirrhotic patients is poorly understood. We hypothesize that patients will have similar rates of liver failure regardless of whether they undergo minimally invasive liver resection (MILR) or open liver resection (OLR) in major liver resections. In contrast, there will be lower rates of PHLF in patients undergoing minor hepatectomy via the MILR approach. Methods: Propensity score matching was used to analyze regression by matching the MILR to the OLR cohort. Patient demographics from the American College of Surgeons National Surgical Quality Improvement Program, including race, age, gender, and ethnicity, were matched. Chronic obstructive pulmonary disease, congestive heart failure, smoking, hypertension, diabetes, renal failure, dyspnea, dialysis dependence, body mass index, and American Society of Anesthesiologists (ASA) classification (>ASA III) were among the preoperative patient characteristics subject to matching. PHLF (Grade A vs B. vs C) was our primary outcome measure. Results: A total of 2129 cirrhotic patients were included in the study. In the minor hepatectomy group, patients undergoing an OLR were more likely to get discharged to a facility (7.0% vs 4.4%; P = .03), had greater hospital length of stay (5 vs 3 days; P = .02), and had a greater need for invasive postoperative interventions (10.7% vs 4.6%; P < .01). They were also noted to have higher rates of organ space superficial surgical infections (SSIs) (7.3% vs 3.7%; P = .003), Clostridium difficile infection (.9% vs .1%; P = .05), renal insufficiency (2.1% vs .1%; P < .01), unplanned intubations (3.1% vs 1.4%; P = .03), and Grade C liver failure (2.3% vs .9%; P = .03). Conclusion: A higher incidence of PHLF grade C was found in patients undergoing OLR in the minor hepatectomy group. Therefore, in cirrhotic patients who can tolerate minimally invasive approaches, MILR should be offered to prevent postoperative complications as part of their optimization plan., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: The authors declare that they have NO affiliations with or involvement in any organization or entity with any financial interest in this manuscript’s subject matter or materials.
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- 2024
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7. Effects of Medicaid managed care on early detection of cancer: Evidence from mandatory Medicaid managed care program in Pennsylvania.
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Kwon Y, Roberts ET, Cole ES, Degenholtz HB, Jacobs BL, and Sabik LM
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- Humans, Pennsylvania, Adult, Middle Aged, United States, Female, Male, Young Adult, Mandatory Programs, Medicaid statistics & numerical data, Early Detection of Cancer statistics & numerical data, Managed Care Programs statistics & numerical data, Neoplasms diagnosis, Neoplasms therapy
- Abstract
Objective: To examine changes in late- versus early-stage diagnosis of cancer associated with the introduction of mandatory Medicaid managed care (MMC) in Pennsylvania., Data Sources and Study Setting: We analyzed data from the Pennsylvania cancer registry (2010-2018) for adult Medicaid beneficiaries aged 21-64 newly diagnosed with a solid tumor. To ascertain Medicaid and managed care status around diagnosis, we linked the cancer registry to statewide hospital-based facility records collected by an independent state agency (Pennsylvania Health Care Cost Containment Council)., Study Design: We leveraged a natural experiment arising from county-level variation in mandatory MMC in Pennsylvania. Using a stacked difference-in-differences design, we compared changes in the probability of late-stage cancer diagnosis among those residing in counties that newly transitioned to mandatory managed care to contemporaneous changes among those in counties with mature MMC programs., Data Collection/extraction Methods: N/A., Principal Findings: Mandatory MMC was associated with a reduced probability of late-stage cancer diagnosis (-3.9 percentage points; 95% CI: -7.2, -0.5; p = 0.02), particularly for screening-amenable cancers (-5.5 percentage points; 95% CI: -10.4, -0.6; p = 0.03). We found no significant changes in late-stage diagnosis among non-screening amenable cancers., Conclusions: In Pennsylvania, the implementation of mandatory MMC for adult Medicaid beneficiaries was associated with earlier stage of diagnosis among newly diagnosed cancer patients with Medicaid, especially those diagnosed with screening-amenable cancers. Considering that over half of the sample was diagnosed with late-stage cancer even after the transition to mandatory MMC, Medicaid programs and managed care organizations should continue to carefully monitor receipt of cancer screening and design strategies to reduce barriers to guideline-concordant screening or diagnostic procedures., (© 2024 Health Research and Educational Trust.)
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- 2024
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8. Kidney Transplantation in ≤15 kg Children: Outcomes and Prognostic Indicators-A Review of the Organ Procurement and Transplantation Database.
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Melikian R, Kwon Y, Kohrman N, Lo M, Emamaullee J, Zielsdorf S, Lestz R, Sher L, and Etesami K
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- Humans, Child, Female, Male, Child, Preschool, Adolescent, Prognosis, Infant, United States epidemiology, Kidney Failure, Chronic surgery, Body Weight, Kaplan-Meier Estimate, Treatment Outcome, Retrospective Studies, Proportional Hazards Models, Infant, Newborn, Kidney Transplantation, Tissue and Organ Procurement methods, Graft Survival, Databases, Factual
- Abstract
Background: Approximately 2500 pediatric patients are awaiting kidney transplantation in the United States, with <5% comprising those ≤15 kg. Transplant in this cohort is often delayed by center-based growth parameters, often necessitating transplantation after the initiation of dialysis. Furthermore, prognostication remains somewhat ambiguous. In this report, we scrutinize the Organ Procurement and Transplantation Network (OPTN) data from 2001 to 2021 to help better understand specific variables impacting graft and patient outcomes in these children., Methods: The OPTN kidney transplant dataset from 2001 to 2021 was analyzed. Inclusion criteria included age <18 years, weight ≤15 kg, and recipient of primary living donor kidney transplantation (LDKT) or deceased donor kidney transplantation (DDKT). Patient and graft survival probabilities were calculated using the Kaplan-Meier method. The Cox proportional hazards model was used to calculate hazard ratio (HR) and identify variables significantly associated with patient and graft survival., Results: Two thousand one hundred sixty-eight pediatric transplant recipients met inclusion criteria. Patient survival at 1 and 3 years was 98% and 97%, respectively. Graft survival at 1 and 3 years was 95% and 92%, respectively. Dialysis was the sole significant variable impacting both patient and graft survival. Graft survival was further impacted by transplant era, recipient gender and ethnicity, and donor type. Infants transplanted at Age 1 had better graft survival compared with older children, and nephrotic syndrome was likewise associated with a better prognosis., Conclusion: Pediatric kidney transplantation is highly successful. The balance between preemptive transplantation, medical optimization, and satisfactory technical parameters seems to suggest a "Goldilocks zone" for many children, favoring transplantation between 1 and 2 years of age., (© 2024 The Author(s). Pediatric Transplantation published by Wiley Periodicals LLC.)
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- 2024
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9. Assessing Medicaid Privatization's Impacts on Cancer Outcomes: Addressing Data Limitations and Policy Factors.
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Kwon Y, Roberts ET, and Sabik LM
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- Humans, United States, Health Policy, Medicaid, Neoplasms epidemiology, Neoplasms therapy, Privatization
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- 2024
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10. Antidepressant discontinuation patterns and characteristics across sociodemographic groups in the United States.
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Kwon Y and Lauffenburger JC
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- Male, Humans, United States, Female, Retrospective Studies, Antidepressive Agents therapeutic use, Antidepressive Agents, Tricyclic
- Abstract
Background: While antidepressants are frequently used, less is known about contemporary discontinuation patterns, especially across different sociodemographic populations., Methods: Patients 16-84 years initiating antidepressants between 2016 and 2019 within a large US health insurer were identified. The association between patient characteristics and time until antidepressant discontinuation was evaluated using adjusted Cox proportional hazard regression., Results: Across 1,365,576 patients, mean time to discontinuation was 168.1 days (SD: 223.6). Men were more likely to discontinue than women (HR: 0.94, 95%CI: 0.94-0.94). Younger patients (16-24 years) were more likely to discontinue than older patients. Patients who were non-White (Asian HR: 1.33, 95%CI: 1.31-1.34; Black HR: 1.27, 95%CI: 1.27-1.28; Hispanic HR: 1.34, 95%:CI 1.34-1.35), with evidence of a substance use disorder (HR: 1.31, 95%CI: 1.27-1.35), or taking tricyclic antidepressants (HR:1.26, 95%CI: 1.25-1.27) were more likely to discontinue., Limitations: Information on reasons for discontinuation was not available, and wide standard deviations for the primary outcome were reported. The results may not be generalized to non-commercially insured beneficiaries., Conclusions: Discontinuation is common within the first 6 months of treatment but varies across populations, highlighting patients who may benefit from potential intervention., Competing Interests: Declaration of competing interest Both authors declare that they have no known competing financial interests or personal relationships to report., (Copyright © 2024 Elsevier B.V. All rights reserved.)
- Published
- 2024
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11. Comparison of primary payer in cancer registry and discharge data.
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Kwon Y, Perraillon MC, Drake C, Jacobs BL, Bradley CJ, and Sabik LM
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- Adult, Aged, Humans, Cross-Sectional Studies, Medicare, Registries, United States, Middle Aged, Neoplasms diagnosis, Neoplasms epidemiology, Patient Discharge
- Abstract
Objectives: To determine agreement between variables capturing the primary payer at cancer diagnosis across the Pennsylvania Cancer Registry (PCR) and statewide facility discharge records (Pennsylvania Health Care Cost Containment Council [PHC4]) for adults younger than 65 years, and to specifically examine factors associated with misclassification of Medicaid status in the registry given the role of managed care., Study Design: Cross-sectional analysis of the primary cancer cases among adults aged 21 to 64 years in the PCR from 2010 to 2016 linked to the PHC4 facility visit records., Methods: We assessed agreement of payer at diagnosis (Medicare, Medicaid, private, other, uninsured, unknown) across data sources, including positive predictive value (PPV) and sensitivity, using the PHC4 records as the gold standard. The probability of misclassifying Medicaid in registry was estimated using multivariate logit models., Results: Agreement of payers was high for private insurance (PPV, 89.7%; sensitivity, 83.6%), but there was misclassification and/or underreporting of Medicaid in the registry (PPV, 80%; sensitivity, 58%). Among cases with "other" and "unknown" insurance, 73.8% and 62.1%, respectively, had private insurance according to the PHC4 records. Medicaid managed care was associated with a statistically significant increase of 12.6 percentage points (95% CI, 9.4-15.8) in the probability of misclassifying Medicaid enrollment as private insurance in the registry., Conclusions: Findings suggest caution in conducting and interpreting research using insurance variables in cancer registries.
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- 2023
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12. Racial and Ethnic Disparities in Health Care Use and Access Associated With Loss of Medicaid Supplemental Insurance Eligibility Above the Federal Poverty Level.
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Roberts ET, Kwon Y, Hames AG, McWilliams JM, Ayanian JZ, and Tipirneni R
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- Humans, Aged, Female, United States, Middle Aged, Male, Cross-Sectional Studies, Poverty, Healthcare Disparities, Medicaid, Medicare
- Abstract
Importance: Medicaid supplemental insurance covers most cost sharing in Medicare. Among low-income Medicare beneficiaries, the loss of Medicaid eligibility above this program's income eligibility threshold (100% of federal poverty level [FPL]) may exacerbate racial and ethnic disparities in Medicare beneficiaries' ability to afford care., Objective: To examine whether exceeding the income threshold for Medicaid, which results in an abrupt loss of Medicaid eligibility, is associated with greater racial and ethnic disparities in access to and use of care., Design, Setting, and Participants: This cross-sectional study used a regression discontinuity design to assess differences in access to and use of care associated with exceeding the income threshold for Medicaid eligibility. We analyzed Medicare beneficiaries with incomes 0% to 200% of FPL from the 2008 to 2018 biennial waves of the Health and Retirement Study linked to Medicare administrative data. To identify racial and ethnic disparities associated with the loss of Medicaid eligibility, we compared discontinuities in outcomes among Black and Hispanic beneficiaries (n = 2885) and White beneficiaries (n = 5259). Analyses were conducted between January 1, 2022, and October 1, 2022., Main Outcome Measures: Patient-reported difficulty accessing care due to cost and outpatient service use, medication fills, and hospitalizations measured from Medicare administrative data., Results: This cross-sectional study included 8144 participants (38 805 person-years), who when weighted represented 151 282 957 person-years in the community-dwelling population of Medicare beneficiaries aged 50 years and older and incomes less than 200% FPL. In the weighted sample, the mean (SD) age was 75.4 (9.4) years, 66.1% of beneficiaries were women, 14.8% were non-Hispanic Black, 13.6% were Hispanic, and 71.6% were White. Findings suggest that exceeding the Medicaid eligibility threshold was associated with a 43.8 percentage point (pp) (95% CI, 37.8-49.8) lower probability of Medicaid enrollment among Black and Hispanic Medicare beneficiaries and a 31.0 pp (95% CI, 25.4-36.6) lower probability of Medicaid enrollment among White beneficiaries. Among Black and Hispanic beneficiaries, exceeding the threshold was associated with increased cost-related barriers to care (discontinuity: 5.7 pp; 95% CI, 2.0-9.4), lower outpatient use (-6.3 services per person-year; 95% CI, -10.4 to -2.2), and fewer medication fills (-6.9 fills per person-year; 95% CI, -11.4 to -2.5), but it was not associated with a statistically significant discontinuity in hospitalizations. Discontinuities in these outcomes were smaller or nonsignificant among White beneficiaries. Consequently, exceeding the threshold was associated with widened disparities, including greater reductions in outpatient service use (disparity: -6.2 services per person-year; 95% CI, -11.7 to -0.6; P = .03) and medication fills (disparity: -7.2 fills per person-year; 95% CI, -13.4 to -1.0; P = .02) among Black and Hispanic vs White beneficiaries., Conclusions and Relevance: This cross-sectional study found that loss of eligibility for Medicaid supplemental insurance above the federal poverty level, which increases cost sharing in Medicare, was associated with increased racial and ethnic health care disparities among low-income Medicare beneficiaries. Expanding eligibility for Medicaid supplemental insurance may narrow these disparities.
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- 2023
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13. Model for End-Stage Liver Disease/Pediatric End-Stage Liver Disease exception policy and outcomes in pediatric patients with hepatopulmonary syndrome requiring liver transplantation.
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Raza MH, Kwon Y, Kobierski P, Misra AC, Lim A, Goldbeck C, Etesami K, Kohli R, and Emamaullee J
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- Adult, Female, Humans, Child, United States epidemiology, Aged, Male, Retrospective Studies, Severity of Illness Index, Policy, Hypoxia complications, Waiting Lists, End Stage Liver Disease complications, End Stage Liver Disease diagnosis, End Stage Liver Disease surgery, Liver Transplantation adverse effects, Hepatopulmonary Syndrome diagnosis, Hepatopulmonary Syndrome surgery
- Abstract
Hepatopulmonary syndrome (HPS) is associated with increased waitlist mortality in liver transplantation (LT) candidates. Children with HPS are granted Model for End-Stage Liver Disease (MELD)/Pediatric End-Stage Liver Disease (PELD) exception points for waitlist prioritization in the United States based on criterion developed for adults. In this study, the impact of this MELD/PELD exception policy on post-LT survival in children was examined. A retrospective cohort of patients aged younger than 18 years with a MELD/PELD exception request who underwent LT between 2007 and 2018 were identified in the Scientific Registry of Transplant Recipients. Patients were stratified by waitlist partial pressure of arterial oxygen (PaO 2 ) to assess risk factors for waitlist mortality and post-LT survival. Among 3082 pediatric LT recipients included in the study, 124 patients (4%) received MELD/PELD exception points for HPS. Patients with HPS were a median age of 9 years (interquartile range: 6, 12 years), 54.8% were girls, and 54% were White. Most patients (87.9%) were listed with laboratory MELD/PELD scores <15. Waitlist mortality for patients with HPS exception points was rare and not different from patients without HPS. When stratified by pre-LT PaO 2 , hypoxemia severity was not associated with differences in 1-, 3-, or 5-year survival rates after LT ( p = 0.13). However, patients with HPS showed a slightly lower survival rate at 5 years compared with patients without HPS (88.7% vs. 93.4%; p = 0.04). MELD/PELD exceptions for children with HPS mitigated waitlist mortality, and recipients with HPS experienced excellent 5-year survival after LT, although slightly lower than in patients without HPS. Unlike adults with HPS, the severity of pre-LT hypoxemia in children does not impact post-LT survival. These data suggest that adult criteria for granting MELD/PELD exception points may not appropriately capture HPS severity in pediatric patients. Further prospective multicenter studies to examine the risk factors predicting negative survival outcomes in children with HPS are warranted., (Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.)
- Published
- 2023
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14. Critical Care Cardiology Trials Network (CCCTN): a cohort profile.
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Metkus TS, Baird-Zars VM, Alfonso CE, Alviar CL, Barnett CF, Barsness GW, Berg DD, Bertic M, Bohula EA, Burke J, Burstein B, Chaudhry SP, Cooper HA, Daniels LB, Fordyce CB, Ghafghazi S, Goldfarb M, Katz JN, Keeley EC, Keller NM, Kenigsberg B, Kontos MC, Kwon Y, Lawler PR, Leibner E, Liu S, Menon V, Miller PE, Newby LK, O'Brien CG, Papolos AI, Pierce MJ, Prasad R, Pisani B, Potter BJ, Roswell RO, Sinha SS, Shah KS, Smith TD, Snell RJ, So D, Solomon MA, Ternus BW, Teuteberg JJ, van Diepen S, Zakaria S, and Morrow DA
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- Humans, United States epidemiology, Coronary Care Units, Critical Care methods, Registries, Critical Illness epidemiology, Cardiology
- Abstract
Aims: The aims of the Critical Care Cardiology Trials Network (CCCTN) are to develop a registry to investigate the epidemiology of cardiac critical illness and to establish a multicentre research network to conduct randomised clinical trials (RCTs) in patients with cardiac critical illness., Methods and Results: The CCCTN was founded in 2017 with 16 centres and has grown to a research network of over 40 academic and clinical centres in the United States and Canada. Each centre enters data for consecutive cardiac intensive care unit (CICU) admissions for at least 2 months of each calendar year. More than 20 000 unique CICU admissions are now included in the CCCTN Registry. To date, scientific observations from the CCCTN Registry include description of variations in care, the epidemiology and outcomes of all CICU patients, as well as subsets of patients with specific disease states, such as shock, heart failure, renal dysfunction, and respiratory failure. The CCCTN has also characterised utilization patterns, including use of mechanical circulatory support in response to changes in the heart transplantation allocation system, and the use and impact of multidisciplinary shock teams. Over years of multicentre collaboration, the CCCTN has established a robust research network to facilitate multicentre registry-based randomised trials in patients with cardiac critical illness., Conclusion: The CCCTN is a large, prospective registry dedicated to describing processes-of-care and expanding clinical knowledge in cardiac critical illness. The CCCTN will serve as an investigational platform from which to conduct randomised controlled trials in this important patient population., (© The Author(s) 2022. Published by Oxford University Press on behalf of the European Society of Cardiology.)
- Published
- 2022
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15. A scoping review of racial/ethnic disparities in sleep.
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Ahn S, Lobo JM, Logan JG, Kang H, Kwon Y, and Sohn MW
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- Health Status Disparities, Hispanic or Latino, Humans, Sleep, United States, White People, Ethnicity, Sleep Apnea Syndromes
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Background: Despite remarkable achievements in ensuring health equity, racial/ethnic disparities in sleep still persist and are emerging as a major area of concern. Accumulating evidence has not yet been well characterized from a broad perspective. We conducted a scoping review of studies on sleep disparities by race/ethnicity to summarize characteristics of existing studies and identify evidence gaps., Methods: We searched PubMed, CINAHL, PsycINFO, and Web of Science databases for studies of racial/ethnic disparities in sleep. Studies that met inclusion criteria were retrieved and organized in a data charting form by study design, sleep measuring methods, sleep features, and racial/ethnic comparisons., Results: One hundred sixteen studies were included in this review. Most studies focused on disparities between Whites and Blacks. Disproportionately fewer studies examined disparities for Hispanic, Asian, and other racial/ethnic groups. Self-reported sleep was most frequently used. Sleep duration, overall sleep quality, and sleep disordered breathing were frequently studied, whereas other features including sleep efficiency, latency, continuity, and architecture were understudied, particularly in racial minority groups in the US. Current study findings on racial/ethnic disparities in most of sleep features is mixed and inconclusive., Conclusions: This review identified significant evidence gaps in racial/ethnic disparities research on sleep. Our results suggest a need for more studies examining diverse sleep features using standardized and robust measuring methods for more valid comparisons of sleep health in diverse race/ethnicity groups., (Copyright © 2021 Elsevier B.V. All rights reserved.)
- Published
- 2021
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16. Prolonged Circulation Time Is Associated With Mortality Among Older Men With Sleep-Disordered Breathing.
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Kwon Y, Sands SA, Stone KL, Taranto-Montemurro L, Alex RM, White DP, Wellman A, Redline S, and Azarbarzin A
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- Aged, Humans, Male, Oximetry, Time Factors, United States epidemiology, Blood Circulation physiology, Cardiovascular Diseases physiopathology, Sleep Apnea Syndromes mortality, Sleep Apnea Syndromes physiopathology
- Abstract
Background: Conventional metrics to evaluate sleep-disordered breathing (SDB) have many limitations, including their inability to identify subclinical markers of cardiovascular (CV) dysfunction., Research Question: Does sleep study-derived circulation time (Ct) predict mortality, independent of CV risks and SDB severity?, Study Design and Methods: We derived average lung to finger Ct (LFCt) from sleep studies in older men enrolled in the multicenter Osteoporotic Fractures in Men (MrOS) Sleep study. LFCt was defined as the average time between end of scored respiratory events and nadir oxygen desaturations associated with those events. We calculated the hazard ratio (HRs) for the CV and all-cause mortality by LFCt quartiles, adjusting for the demographic characteristics, body habitus, baseline CV risk, and CV disease (CVD). Additional models included apnea-hypopnea index (AHI), time with oxygen saturation as measured by pulse oximetry (SpO
2 ) < 90% (T90), and hypoxic burden. We also repeated analyses after excluding those with CVD at baseline., Results: A total of 2,631 men (mean ± SD age, 76.4 ± 5.5 years) were included in this study. LFCt median (interquartile range) was 18 (15-22) s. During an average ± SD follow-up of 9.9 ± 3.5 years, 427 men (16%) and 1,205 men (46%) experienced CV death and all-cause death, respectively. In multivariate analysis, men in the fourth quartile of LFCt (22-52 s) had an HR of 1.36 (95% CI, 1.02-1.81) and 1.35 (95% CI, 1.14-1.60) for CV and all-cause mortality, respectively, when compared with men in the first quartile (4-15 s). The results were similar when additionally adjusting for AHI, T90, or hypoxic burden. Results were stronger among men with no history of CVD at baseline., Interpretation: LFCt is associated with both CV and all-cause mortality in older men, independent of baseline CV burden and SDB metrics. LFCt may be a novel physiologic marker for subclinical CVD and adverse outcomes in patients with SDB., (Copyright © 2020 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)- Published
- 2021
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17. Association of Retinal Microvascular Signs with Incident Atrial Fibrillation: The Multi-Ethnic Study of Atherosclerosis.
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Lin GM, Colangelo LA, Klein BEK, Cotch MF, Wong TY, Cheung CY, Heckbert SR, Alonso A, Kwon Y, Kronmal RA, Lloyd-Jones DM, and Liu K
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- Aged, Aged, 80 and over, Atrial Fibrillation ethnology, Atrial Fibrillation physiopathology, Female, Humans, Incidence, Male, Middle Aged, Retinal Diseases ethnology, Retrospective Studies, Risk Factors, United States epidemiology, Atrial Fibrillation complications, Ethnicity, Microvessels diagnostic imaging, Retinal Diseases diagnosis, Retinal Vessels diagnostic imaging
- Abstract
Purpose: Microvascular diseases may contribute to the occurrence of atrial fibrillation (AF). Retinal microvascular signs that are similar to other microvasculature in the body and can be visualized directly via ophthalmoscopy may provide insights into such a relationship., Design: Prospective, longitudinal, multiethnic study., Participants: We examined the association between retinal microvascular signs and incident AF in 4994 participants 47 to 86 years of age and free of prior AF who underwent fundus photography from 2002 through 2004 and were followed up through 2015 in the Multi-Ethnic Study of Atherosclerosis (MESA)., Methods: Retinal microvascular signs evaluated include central retinal arteriolar equivalent and central retinal venular equivalent (CRVE) and presence of any retinopathy signs (e.g., retinal microaneurysms or hemorrhages). A multivariate Cox regression analysis was used to determine the relationship while adjusting for traditional risk factors, alcohol intake, body mass index, diabetes status, chronic kidney disease status, hemoglobin A1c level, C-reactive protein level, medications, and prevalent cardiovascular diseases or heart failure., Main Outcome and Measures: Incident AF events were identified using 12-lead electrocardiographic findings, hospital discharge records, and Medicare claims data., Results: During a median follow-up of 14.1 years, 643 AF events were identified. No association was found between any retinal microvascular signs and incident AF except for retinal focal arteriolar narrowing (hazard ratio, 1.75; 95% confidence interval, 1.06-2.87) in the overall population. However, in the subgroup analyses by gender, wider CRVE was associated with a higher risk of incident AF in women, but not in men (hazard ratio for every 10-μm increase in CRVE, 1.08 [95% confidence interval, 1.01-1.15] and 0.97 [95% confidence interval, 0.92-1.03], respectively; P = 0.041 for interaction)., Conclusions: No consistent pattern of association was found between retinal microvascular signs and incident AF. We observed an association in women, but not in men, of wider retinal venular calibers with incidence of AF. The reasons for a possible interaction are incompletely understood., (Copyright © 2020 American Academy of Ophthalmology. All rights reserved.)
- Published
- 2021
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18. Association of obesity with arterial stiffness: The Multi-Ethnic Study of Atherosclerosis (MESA).
- Author
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Logan JG, Kang H, Kim S, Duprez D, Kwon Y, Jacobs DR Jr, Forbang N, Lobo JM, and Sohn MW
- Subjects
- Aged, Aged, 80 and over, Body Mass Index, Cardiovascular Diseases diagnosis, Cardiovascular Diseases ethnology, Cross-Sectional Studies, Female, Humans, Male, Middle Aged, Obesity diagnosis, Obesity ethnology, Prognosis, Risk Factors, Time Factors, United States epidemiology, Waist-Hip Ratio, Adiposity ethnology, Cardiovascular Diseases physiopathology, Obesity physiopathology, Vascular Stiffness
- Abstract
Arterial stiffness (AS) and obesity are recognized as important risk factors of cardiovascular disease (CVD). The purpose of this study was to investigate the relationship between AS and obesity. AS was defined as high augmentation index (AIx) and low elasticity (C1, large artery elasticity; C2, small artery elasticity) in participants enrolled in the Multi-Ethnic Study of Atherosclerosis at baseline. We compared AIx, C1, and C2 by body mass index (BMI) (< 25, 25-29.9, 30-39.9, ⩾ 40 kg/m
2 ) and waist-hip ratio (WHR) (< 0.85, 0.85-0.99, ⩾ 1). The obesity-AS association was tested across 10-year age intervals. Among 6177 participants (62 ± 10 years old, 52% female), a significant inverse relationship was observed between obesity and AS. After adjustments for CVD risk factors, participants with a BMI > 40 kg/m2 had 5.4% lower AIx (mean difference [Δ] = -0.82%; 95% CI: -1.10, -0.53), 15.4% higher C1 (Δ = 1.66 mL/mmHg ×10; 95% CI: 1.00, 2.33), and 40.2% higher C2 (Δ = 1.49 mL/mmHg ×100; 95% CI: 1.15, 1.83) compared to those with a BMI < 25 kg/m2 (all p for trend < 0.001). Participants with a WHR ⩾ 1 had 5.6% higher C1 (∆ = 0.92 mL/mmHg ×10; 95% CI: 0.47, 1.37) compared to those with a WHR < 0.85. The WHR had a significant interaction with age on AIx and C2, but not with BMI; the inverse relationships of the WHR with AIx and C2 were observed only in participants < 55 years between the normal (WHR < 0.85) and the overweight (0.85 ⩽ WHR < 0.99) groups. Different associations of WHR and BMI with arterial stiffness among older adults should be further investigated.- Published
- 2020
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19. Development of a COVID-19 Point-of-Care Ultrasound Protocol.
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Huang G, Vengerovsky A, Morris A, Town J, Carlbom D, and Kwon Y
- Subjects
- Betacoronavirus, COVID-19, Critical Care, Humans, SARS-CoV-2, United States, Coronavirus Infections, Echocardiography, Pandemics, Pneumonia, Viral, Point-of-Care Systems
- Published
- 2020
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20. Economic and Humanistic Burden of Cervical Cancer in the United States: Results from a Nationally Representative Survey.
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Shah R, Nwankwo C, Kwon Y, and Corman SL
- Subjects
- Activities of Daily Living, Case-Control Studies, Cohort Studies, Cross-Sectional Studies, Female, Health Expenditures, Health Surveys, Humans, Retrospective Studies, United States, Cost of Illness, Quality of Life, Uterine Cervical Neoplasms economics
- Abstract
Objective: To measure the economic and humanistic burden of cervical cancer in the United States. Materials and Methods: This was a retrospective analysis of Medical Expenditure Panel Survey data (2006-2015). Cervical cancer cases were identified using International Classification of Diseases, Ninth Revision, Clinical Modification code "180" or clinical classification software code "26". The control group included women without any cancer diagnosis. Study outcomes included health care resource use (institutional inpatient and outpatient, emergency room, and physician office visits), costs, limitations in activities of daily living, and quality of life (general health status, 12-Item Short Form Health Survey [SF-12] physical and mental component summary [MCS], EuroQol-5D and Short-Form Six-Dimension health utility, and Patient Health Questionnaire-2 depression severity). Generalized linear models, controlling for sociodemographic and clinical covariates, were conducted to compare outcomes between cases and controls. Results: The analytic cohort included 275,246 cervical cancer cases and 146,061,609 noncancer controls. Cases were significantly older (mean age [years]: 42.03 vs. 36.98) and had a higher Charlson comorbidity burden (mean score: 1.06 vs. 0.46) versus controls. Multivariate analyses suggested that compared to controls, cancer cases had significantly higher costs: institutional outpatient ($1,610 vs. $502), physician visit ($2,422 vs. $1,321), and total health care ($10,031 vs. $4,913). Cases were 1.99 (odds ratio [OR]: 1.991; 95% confidence interval [CI]: 1.23-3.22) and 2.56 (OR: 2.562; 95% CI: 1.78-3.68) times as likely to report activity limitations and poor general health versus controls. Cervical cancer patients had significantly lower SF-12 physical and MCS score, health utility, and higher depression severity. Conclusions: Cervical cancer is associated with significant economic burden, activity limitations, and quality of life impairment among ambulatory women in the United States.
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- 2020
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21. A Routine Activity Approach to Understand Cybergrooming Victimization Among Adolescents from Six Countries.
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Wachs S, Michelsen A, Wright MF, Gámez-Guadix M, Almendros C, Kwon Y, Na EY, Sittichai R, Singh R, Biswal R, Görzig A, and Yanagida T
- Subjects
- Adolescent, Child, Cross-Sectional Studies, Female, Germany, Humans, India, Internet statistics & numerical data, Male, Parenting psychology, Privacy psychology, Republic of Korea, Self Disclosure, Spain, Thailand, United States, Adolescent Behavior psychology, Crime Victims psychology, Cyberbullying psychology
- Abstract
Little attention has been given academically to empirically tested theoretical frameworks that aim at measuring the risk of adolescents falling victim to cybergrooming. To this end, we have applied the routine activity theory (RAT) to investigate whether exposure to motivated offenders (PC/laptop ownership and Internet access in one's own bedroom), capable guardianship (parental mediation strategies of Internet use), and target suitability (adolescents' online disclosure of private information) might predict cybergrooming victimization among adolescents. Using data from a cross-sectional survey of 5,938 adolescents from Germany, India, South Korea, Spain, Thailand, and the United States, ranging in age from 12 to 18 ( M = 14.77, SD = 1.60), we found that PC/laptop ownership and Internet access in one's own bedroom, parental mediation, and online disclosure are all directly associated with cybergrooming victimization. Although instructive parental mediation is negatively related to online disclosure and cybergrooming victimization, restrictive mediation is positively related to both. In addition, online disclosure partially mediated the relationship between parental mediation and cybergrooming victimization. The analyses confirm the effectiveness of applying RAT to cybergrooming. Moreover, this study highlights the need for prevention programs, including lessons on age-appropriate information and communication technology usage and access, to educate parents on using instructive strategies of Internet mediation, and inform adolescents about how to avoid disclosing too much private information online. RAT could function as a theoretical framework for these programs.
- Published
- 2020
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22. Economic-Burden Trajectories in Commercially Insured US Infants With Respiratory Syncytial Virus Infection.
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Chirikov VV, Simões EAF, Kuznik A, Kwon Y, and Botteman M
- Subjects
- Asthma economics, Female, Gestational Age, Hospitalization economics, Humans, Infant, Infant, Low Birth Weight, Infant, Newborn, Infant, Premature, Male, Respiratory Sounds, Respiratory Syncytial Virus, Human pathogenicity, Retrospective Studies, United States, Respiratory Syncytial Virus Infections economics
- Abstract
Background: This study evaluates the long-term respiratory syncytial virus (RSV) burden among preterm and full-term infants in the United States., Methods: Infants with birth hospitalization claims and ≥24 months of continuous enrollment were retrospectively identified in the Truven MarketScan Commercial Claims and Encounters database for the period 1 January 2004-30 September 2015. Infants with RSV infection in the first year of life (n = 38 473) were matched to controls (n = 76 825), and remaining imbalances in the number of individuals in each group were adjusted using propensity score methods. All-cause, respiratory-related, and asthma/wheezing-related 5-year average cumulative costs were measured., Results: Early premature (n = 213), premature (n = 397), late premature (n = 4446), and full-term (n = 33 417) RSV-infected infants were matched to 424, 791, 8875, and 66 735 controls, respectively. After 2 years since RSV diagnosis, all-cause cumulative costs for RSV-infected infants as compared to those for controls increased by $22 081 (95% confidence interval [CI], -$5800-$42 543) for early premature infants, by $14 034 (95% CI, $5095- $22 973) for premature infants, by $10 164 (95% CI, $8835-$11 493) for late premature infants, and by $5404 (95% CI, $5110-$5698) for full-term infants. The 5-year RSV burden increased to $39 490 (95% CI, $18 217-$60 764), $23 160 (95% CI, $13 002-$33 317),$13 755 (95% CI, $12 097-$15 414), and $6631 (95% CI, $6060-$7202), respectively. The RSV burden was higher when stratified by inpatient and outpatient setting and respiratory-related and asthma/wheezing-related costs., Conclusions: The RSV burden extends across cost domains and prematurity, with the greatest burden incurred by the second year of follow-up. Findings are useful in determining the cost-effectiveness of RSV therapies in development., (© The Author(s) 2019. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail: journals.permissions@oup.com.)
- Published
- 2020
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23. Oral corticosteroid exposure and increased risk of related complications in patients with noninfectious intermediate, posterior, or panuveitis: Real-world data analysis.
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Chirikov VV, Shah R, Kwon Y, and Patel D
- Subjects
- Administration, Oral, Data Analysis, Dose-Response Relationship, Drug, Female, Follow-Up Studies, Glucocorticoids administration & dosage, Glucocorticoids adverse effects, Humans, Male, Middle Aged, Panuveitis epidemiology, Prednisone administration & dosage, Propensity Score, Retrospective Studies, Risk Factors, Time Factors, United States epidemiology, Uveitis, Intermediate epidemiology, Uveitis, Posterior epidemiology, Drug-Related Side Effects and Adverse Reactions epidemiology, Panuveitis drug therapy, Prednisone adverse effects, Uveitis, Intermediate drug therapy, Uveitis, Posterior drug therapy, Visual Acuity
- Abstract
Purpose: This study causally examined the dose-response relationship between oral corticosteroids (OCS) exposure and long-term complications among noninfectious uveitis adult patients in the United States., Methods: The study design was longitudinal, retrospective cohort using Truven Health MarketScan claims database years 2000-2015. The index date was the first day after diagnosis on which OCS≥ 5 mg prednisone equivalent was administered. The period following the index date was parsed into quarters for tracking OCS-related complications; follow-up time was censored when patients switched off of OCS monotherapy. Each quarter of follow-up was divided into 4 groups based on the mean cumulative daily OCS dose (< 7.5 mg; 7.5 to < 30 mg; 30 to < 60 mg; and ≥ 60 mg) and covariate balancing propensity scoring was used to balance groups on baseline characteristics in the first quarter post-index. Marginal structural models (MSMs) were employed to account for time-varying endogeneity between temporal changes in mean cumulative OCS dose and the risk of complications. Patients with systemic autoimmune conditions at baseline were excluded., Results: The study sample included 3966 patients with a median follow-up of 2 years. Compared to those receiving < 7.5 mg, patients with higher mean cumulative OCS dose had 10%, 16%, and 28% higher risk, respectively, of any OCS-related complication in any given quarter., Conclusions: A moderate dose-response relationship was found between the long-term use of OCS monotherapy and the risk of developing complications in noninfectious intermediate, posterior, or panuveitis patients. Future research should examine optimal approaches to achieve inflammation control while minimizing OCS exposure.
- Published
- 2019
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24. Consumer Sleep Technologies: How to Balance the Promises of New Technology with Evidence-Based Medicine and Clinical Guidelines.
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Khosla S, Deak MC, Gault D, Goldstein CA, Hwang D, Kwon Y, O'Hearn D, Schutte-Rodin S, Yurcheshen M, and Kirsch DB
- Subjects
- Academies and Institutes, Humans, United States, Evidence-Based Medicine, Sleep
- Published
- 2019
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25. Obstructive Sleep Apnea and Structural/Functional Properties of the Thoracic Ascending Aorta: The Multi-Ethnic Study of Atherosclerosis (MESA).
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Kwon Y, Logan J, Redline S, Duprez D, Jacobs DR Jr, Ouyang P, Hundley WG, Lima J, Bluemke DA, and Lutsey PL
- Subjects
- Aged, Aged, 80 and over, Cardiovascular Diseases ethnology, Female, Humans, Independent Living, Linear Models, Magnetic Resonance Imaging, Male, Middle Aged, Polysomnography, Pulse Wave Analysis, Severity of Illness Index, Sex Characteristics, Sleep Apnea, Obstructive ethnology, United States epidemiology, United States ethnology, Vascular Stiffness, Aorta, Thoracic pathology, Aorta, Thoracic physiopathology, Cardiovascular Diseases epidemiology, Sleep Apnea, Obstructive epidemiology, Vascular Remodeling
- Abstract
Background: Structural and functional properties of the proximal thoracic aorta have important implications in clinical and subclinical cardiovascular disease (CVD). We examined whether obstructive sleep apnea (OSA) is associated with proximal aortic size and aortic stiffness in a multi-ethnic community-based cohort., Methods: The sample included the Multi-Ethnic Study of Atherosclerosis (MESA) Sleep Ancillary study participants without known CVD who underwent cardiac magnetic resonance imaging. The main exposure variable was OSA severity based on the polysomnography-derived apnea hypopnea index (AHI; normal, AHI <5/h; mild, 5≤ AHI <15/h; moderate to severe, AHI ≥15/h). The study outcomes were ascending aortic diameter (AoD, cm), aortic pulse wave velocity (AoPWV, m/s), and ascending aortic distensibility (AAD, %/mm Hg). Analyses were performed in the overall sample and in sex-specific strata, adjusted for multiple potential confounders., Results: The 708 participants were 55.9% female and on average 68 years old (54-93 years). There was a significant trend (p < 0.0001) of greater mean (SD) AoD across the three OSA groups: normal (n = 87), 3.13 cm (0.35); mild (n = 215), 3.25 (0.34); moderate to severe (n = 406), 3.37 (0.36). In adjusted analysis, participants with moderate to severe OSA had a greater mean AoD compared with the normal group: adjusted mean difference (95% CI), 0.12 cm (0.05, 0.20), p = 0.002. This AoD gradient was observed in women but not in men (p for interaction = 0.02). No differences were found in AoPWV or AAD among the OSA groups., Conclusion: In a diverse community-based cohort, moderate to severe OSA (vs. no OSA) was associated with a larger ascending AoD in women., (© 2019 S. Karger AG, Basel.)
- Published
- 2019
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26. Tree species richness predicted using a spatial environmental model including forest area and frost frequency, eastern USA.
- Author
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Kwon Y, Larsen CPS, and Lee M
- Subjects
- Ecosystem, Models, Statistical, Models, Theoretical, Regression Analysis, Spatial Analysis, Trees, United States, Biodiversity, Forecasting methods, Forests
- Abstract
Assessing geographic patterns of species richness is essential to develop biological conservation as well as to understand the processes that shape these patterns. We aim to improve geographic prediction of tree species richness (TSR) across eastern USA by using: 1) gridded point-sample data rather than spatially generalized range maps for the TSR outcome variable, 2) new predictor variables (forest area FA; mean frost day frequency MFDF) and 3) regression models that account for spatial autocorrelation. TSR was estimated in 50 km by 50 km grids using Forest Inventory and Analysis (FIA) point-sample data. Eighteen environmental predictor variables were employed, with the most effective set selected by a LASSO that reduced multicollinearity. Those predictors were then employed in Generalized linear models (GLMs), and in Eigenvector spatial filtering (ESF) models that accounted for spatial autocorrelation. Models were evaluated by model fit statistics, spatial patterns of TSR predictions, and spatial autocorrelation. Our results showed gridded TSR was best-predicted by the ESF model that used, in descending order of influence: precipitation seasonality, mean precipitation in the driest quarter, FA, and MFDF. ESF models, by accounting for spatial autocorrelation, outperformed GLMs regardless of the predictors employed, as indicated by percent deviance explained and spatial autocorrelation of residuals. Small regions with low TSR, such as the Midwest prairie peninsula, were successfully predicted by ESF models, but not by GLMs or other studies. Gridded TSR in Florida was only correctly predicted by the ESF model with FA and MFDF, and was over-predicted by all other models., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2018
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27. Consumer Sleep Technology: An American Academy of Sleep Medicine Position Statement.
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Khosla S, Deak MC, Gault D, Goldstein CA, Hwang D, Kwon Y, O'Hearn D, Schutte-Rodin S, Yurcheshen M, Rosen IM, Kirsch DB, Chervin RD, Carden KA, Ramar K, Aurora RN, Kristo DA, Malhotra RK, Martin JL, Olson EJ, Rosen CL, and Rowley JA
- Subjects
- Humans, Organizational Policy, Polysomnography methods, Polysomnography standards, Self Care standards, Sleep Medicine Specialty instrumentation, Societies, Medical, United States, Polysomnography instrumentation, Self Care instrumentation, Sleep Medicine Specialty standards
- Abstract
Abstract: Consumer sleep technologies (CSTs) are widespread applications and devices that purport to measure and even improve sleep. Sleep clinicians may frequently encounter CST in practice and, despite lack of validation against gold standard polysomnography, familiarity with these devices has become a patient expectation. This American Academy of Sleep Medicine position statement details the disadvantages and potential benefits of CSTs and provides guidance when approaching patient-generated health data from CSTs in a clinical setting. Given the lack of validation and United States Food and Drug Administration (FDA) clearance, CSTs cannot be utilized for the diagnosis and/or treatment of sleep disorders at this time. However, CSTs may be utilized to enhance the patient-clinician interaction when presented in the context of an appropriate clinical evaluation. The ubiquitous nature of CSTs may further sleep research and practice. However, future validation, access to raw data and algorithms, and FDA oversight are needed., (© 2018 American Academy of Sleep Medicine.)
- Published
- 2018
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28. Development and validity of a scale to measure workplace culture of health.
- Author
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Kwon Y, Marzec ML, and Edington DW
- Subjects
- Adult, Factor Analysis, Statistical, Female, Health Care Sector organization & administration, Humans, Male, Manufacturing Industry organization & administration, Middle Aged, Psychometrics, Reproducibility of Results, Surveys and Questionnaires, United States, Workplace, Health Promotion organization & administration, Occupational Health, Organizational Culture
- Abstract
Objective: To describe the development of and test the validity and reliability of the Workplace Culture of Health (COH) scale., Methods: Exploratory factor analysis and confirmatory factor analysis were performed on data from a health care organization (N = 627). To verify the factor structure, confirmatory factor analysis was performed on a second data set from a medical equipment manufacturer (N = 226)., Results: The COH scale included a structure of five orthogonal factors: senior leadership and polices, programs and rewards, quality assurance, supervisor support, and coworker support. With regard to construct validity (convergent and discriminant) and reliability, two different US companies showed the same factorial structure, satisfactory fit statistics, and suitable internal and external consistency., Conclusions: The COH scale represents a reliable and valid scale to assess the workplace environment and culture for supporting health.
- Published
- 2015
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29. Molecular survey of bacterial communities associated with bacterial chondronecrosis with osteomyelitis (BCO) in broilers.
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Jiang T, Mandal RK, Wideman RF Jr, Khatiwara A, Pevzner I, and Min Kwon Y
- Subjects
- Animals, Bacteria classification, Bacteria genetics, Chickens, Lameness, Animal epidemiology, Osteochondrosis epidemiology, Osteochondrosis etiology, Osteomyelitis epidemiology, Osteomyelitis etiology, Phylogeny, Polymerase Chain Reaction, Poultry Diseases epidemiology, RNA, Ribosomal, 16S analysis, RNA, Ribosomal, 16S genetics, Risk Factors, United States epidemiology, Animal Husbandry methods, Bacterial Infections complications, Lameness, Animal etiology, Necrosis, Osteochondrosis veterinary, Osteomyelitis veterinary, Poultry Diseases etiology
- Abstract
Bacterial chondronecrosis with osteomyelitis (BCO) is recognized as an important cause of lameness in commercial broiler chickens (meat-type chickens). Relatively little is known about the microbial communities associated with BCO. This study was conducted to increase our understanding of the microbial factors associated with BCO using a culture-independent approach. Using Illumina sequencing of the hyper-variable region V6 in the 16S rRNA gene, we characterized the bacterial communities in 97 femoral or tibial heads from normal and lame broilers carefully selected to represent diverse variations in age, line, lesion type, floor type, clinical status and bone type. Our in-depth survey based on 14 million assembled sequence reads revealed that complex bacterial communities exist in all samples, including macroscopically normal bones from clinically healthy birds. Overall, Proteobacteria (mean 90.9%) comprised the most common phylum, followed by Firmicutes (6.1%) and Actinobacteria (2.6%), accounting for more than 99% of all reads. Statistical analyses demonstrated that there are differences in bacterial communities in different types of bones (femur vs. tibia), lesion types (macroscopically normal femora or tibiae vs. those with pathognomonic BCO lesions), and among individual birds. This analysis also showed that BCO samples overrepresented genera Staphylococcus, whose species have been frequently isolated in BCO samples in previous studies. Rarefaction analysis demonstrated the general tendency that increased severities of BCO lesions were associated with reduced species diversity in both femoral and tibial samples when compared to macroscopically normal samples. These observations suggest that certain bacterial subgroups are preferentially selected in association with the development of BCO lesions. Understanding the microbial species associated with BCO will identify opportunities for understanding and modulating the pathogenesis of this form of lameness in broilers.
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- 2015
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30. An assessment of the optimal scale for monitoring of MODIS and FIA NPP across the eastern USA.
- Author
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Kwon Y and Larsen CP
- Subjects
- Biomass, Models, Theoretical, United States, Environmental Monitoring methods, Satellite Imagery, Trees
- Abstract
Robust monitoring of carbon sequestration by forests requires the use of multiple data sources analyzed at a common scale. To that end, model-based Moderate Resolution Imaging Spectroradiometer (MODIS) and field-based Forest Inventory and Analysis (FIA) data of net primary productivity (NPP) were compared at increasing levels of spatial aggregation across the eastern USA. A total of 52,167 FIA plots and colocated MODIS forest cover NPP pixels were analyzed using a hexagonal tiling system. A protocol was developed to assess the optimal scale as an optimal size of landscape patches at which to map spatially explicit estimates of MODIS and FIA NPP. The optimal mapping resolution (hereafter referred to as optimal scale) is determined using spatially scaled z-statistics as the tradeoff between increased spatial agreement as measured by Pearson's correlation coefficient and decreased details of coverage as measured by the number of hexagons. Spatial sensitivity was also assessed using land cover assessment and forest homogeneity using spatially scaled z-statistics. Pearson correlations indicate that MODIS and FIA NPP are most highly correlated when using large hexagons, while z-statistics indicate an optimal scale at an intermediate hexagon size of 390 km(2). This optimal scale had more spatial detail than was obtained for larger hexagons and greater spatial agreement than was obtained for smaller hexagons. The z-statistics for land cover assessment and forest homogeneity also indicated an optimal scale of 390 km(2).
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- 2013
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31. Development and evaluation of candidate recombinant Salmonella-vectored Salmonella vaccines.
- Author
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Wolfenden RE, Layton SL, Wolfenden AD, Khatiwara A, Gaona-Ramírez G, Pumford NR, Cole K, Kwon YM, Tellez G, Bergman LR, and Hargis BM
- Subjects
- Animals, Enteritis epidemiology, Enteritis veterinary, Genetic Vectors, Hypersensitivity, Delayed immunology, Hypersensitivity, Delayed veterinary, Recombinant Proteins immunology, Salmonella immunology, Salmonella isolation & purification, Salmonella Infections, Animal epidemiology, Salmonella typhimurium immunology, Salmonella typhimurium isolation & purification, United States epidemiology, Salmonella Infections, Animal immunology, Salmonella Vaccines genetics
- Abstract
Attenuated Salmonella Enteriditis (ΔSE) recombinant vaccine vectors incorporating a Salmonella flagellar filament protein (fliC) subunit, a putative cell-mediated epitope, for expression of the lamB gene (encoding a maltose outer membrane porin), with or without co-expression of a putative immune-enhancing CD154 oligopeptide, were developed and compared with wild-type Salmonella Enteriditis (experiments 1 and 2) or the attenuated ΔSE empty vector (experiment 3) as initial vaccine candidates against Salmonella infection. A total of 3 experiments were performed to assess the infection and clearance rate of each of these constructs. Each construct or Salmonella Enteriditis was orally administered to broiler chicks at day of hatch by oral gavage (~10(8) cfu/chick). In experiments 1 to 3, liver-spleen and cecal tonsils were removed aseptically for recovery of wild-type Salmonella Enteriditis or ΔSE mutants. These experiments suggested that cell surface expression of fliC alone markedly increased the clearance rate of the vector at or before 21d postvaccination in all 3 experiments. In a fourth experiment, broilers were vaccinated with one of the vaccine constructs or the ΔSE empty vector and then challenged with wild-type Salmonella Typhimurium. At 19 d posthatch, 16 d postinfection, neither candidate protected against challenge significantly better than the ΔSE empty vector, although there was significantly less Salmonella recovered from vaccinated chickens as compared with nonvaccinated controls. These experiments indicate that these experimental vaccines did not protect against heterologous challenge or enhance clearance after Salmonella Typhimurium challenge; as such, their value as vaccines is limited. The increased clearance of the candidate vaccines, particularly the vector expressing fliC alone, may have value in that the fliC epitope may decrease the clearance time of other recombinant vectored Salmonella vaccines.
- Published
- 2010
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32. Association between household income and overweight of Korean and American children: trends and differences.
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Kwon Y, Oh S, Park S, and Park Y
- Subjects
- Body Mass Index, Child, Dietary Carbohydrates administration & dosage, Dietary Proteins administration & dosage, Energy Intake, Female, Humans, Life Style, Male, Republic of Korea epidemiology, Restaurants, Risk Factors, Sex Factors, Television, United States epidemiology, Income, Overweight epidemiology
- Abstract
The prevalence of overweight in children has been dramatically increasing worldwide, and socioeconomic status is an important risk factor. The purpose of this study was to examine the hypothesis that household income is negatively associated with overweight in Korean and American girls and boys. In the study, 2117 children 7 to 12 years of age from the Korean National Health and Nutrition Examination Survey between 2001 and 2007 and 3016 children from the US National Health and Nutrition Examination Survey between 2001 and 2006 were included. Overweight is defined as the sex- and age-specific body mass index cutoffs recommended by the International Obesity Task Force. Lower household income significantly increased the risk for overweight in Korean boys, irrespective of adjustments. The negative association between household income and overweight of American boys disappeared after adjusting for the frequency of dining out and TV viewing time. There was no significant association between household income and overweight of Korean and American girls. As household income increased, the intake of energy from protein was increased, but energy from carbohydrates was decreased in Korean boys. On the other hand, as household income increased, energy intake from carbohydrates was increased and energy intake from proteins decreased in American boys. In conclusion, positive association between household income and overweight was found in Korean boys, but not in Korean girls and American boys and girls. Effects solely targeting reduction in income disparities cannot effectively reduce sex disparities in overweight of children., (Copyright 2010 Elsevier Inc. All rights reserved.)
- Published
- 2010
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33. Replicating the positivity effect in picture memory in Koreans: evidence for cross-cultural generalizability.
- Author
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Kwon Y, Scheibe S, Samanez-Larkin GR, Tsai JL, and Carstensen LL
- Subjects
- Adult, Aged, Association Learning, Female, Humans, Korea, Male, Middle Aged, Recognition, Psychology, United States, Young Adult, Aging psychology, Attention, Cross-Cultural Comparison, Emotions, Memory, Short-Term, Pattern Recognition, Visual
- Abstract
Older adults' relatively better memory for positive over negative material (positivity effect) has been widely observed in Western samples. This study examined whether a relative preference for positive over negative material is also observed in older Koreans. Younger and older Korean participants viewed images from the International Affective Picture System (IAPS), were tested for recall and recognition of the images, and rated the images for valence. Cultural differences in the valence ratings of images emerged. Once considered, the relative preference for positive over negative material in memory observed in older Koreans was indistinguishable from that observed previously in older Americans., ((c) 2009 APA, all rights reserved.)
- Published
- 2009
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34. The National Institute on Aging/Alzheimer's Association recommendations on the application of apolipoprotein E genotyping to Alzheimer's disease.
- Author
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Relkin NR, Kwon YJ, Tsai J, and Gandy S
- Subjects
- Alleles, Alzheimer Disease diagnosis, Apolipoprotein E4, Gene Frequency, Genotype, Heterozygote, Humans, Odds Ratio, United States, Alzheimer Disease genetics, Apolipoproteins E genetics, Genetic Testing, National Institutes of Health (U.S.)
- Abstract
In a conference held in Chicago during October 1995, a working group of the National Institute of Aging (NIA) and the Alzheimer's Association (AlzA) drafted consensus recommendations on research and clinical applications of APOE genetic susceptibility testing for Alzheimer's disease (AD). The NIA/AlzA Working Group concluded that in considering future applications of APOE genotyping and other knowledge that has been gained about the genetic basis of AD, the interests of AD patients and their family members must be held paramount. The group acknowledged that a robust association exists between possession of the APOE epsilon 4 allele and the risk of late-onset AD and cited evidence that this allele is more strongly associated with AD than any other form of dementia. They recommended against the use of APOE genotyping to predict the-future development of AD in asymptomatic individuals at this time, and warned against the use of the test in isolation as the sole means for diagnosing AD. The group endorsed the concept of discretionary use of APOE genotyping as an adjunct to other AD diagnostic procedures. However, routine clinical use of the test for this purpose was not recommended at this time. Physicians were advised to weigh any potential benefits of testing against the possibility that genotype disclosure could adversely affect the insurability, employability, and social standing of AD patients and their family members. Adequate provisions for pre-test and post-test counseling and psychosocial support were advised for all future clinical and research applications of APOE genotyping. The group called for the development of improved protocols for AD genetic counseling as well as supplemental measures to assure genetic privacy for AD patients and their family members.
- Published
- 1996
- Full Text
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