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Full-Text Articles in Physical Sciences and Mathematics

Oxidative Stress And Cardiovascular Risk In Type 1 Diabetes Mellitus: Insights From The Dcct/Edic Study, W. Wilson Tang, P. Mcgee, John M. Lachin, D. Li, B. Hoogwerf, S. Hazen, +Several Additional Authors May 2018

Oxidative Stress And Cardiovascular Risk In Type 1 Diabetes Mellitus: Insights From The Dcct/Edic Study, W. Wilson Tang, P. Mcgee, John M. Lachin, D. Li, B. Hoogwerf, S. Hazen, +Several Additional Authors

Epidemiology Faculty Publications

Background--Hyperglycemia leading to increased oxidative stress is implicated in the increased risk for the development of macrovascular and microvascular complications in patients with type 1 diabetes mellitus. Methods and Results--A random subcohort of 349 participants was selected from the DCCT/EDIC (Diabetes Control and Complications Trial/Epidemiology of Diabetes Interventions and Complications) cohort. This included 320 controls and 29 cardiovascular disease cases that were augmented with 98 additional known cases to yield a case cohort of 447 participants (320 controls, 127 cases). Biosamples from DCCT baseline, year 1, and closeout of DCCT, and 1 to 2 years post-DCCT (EDIC years 1 and …


Physical Activity Across The Lifespan And Liver Cancer Incidence In The Nih-Aarp Diet And Health Study Cohort., Hannah Arem, Erikka Loftfield, Pedro F Saint-Maurice, Neal D Freedman, Charles E Matthews Apr 2018

Physical Activity Across The Lifespan And Liver Cancer Incidence In The Nih-Aarp Diet And Health Study Cohort., Hannah Arem, Erikka Loftfield, Pedro F Saint-Maurice, Neal D Freedman, Charles E Matthews

Epidemiology Faculty Publications

While liver cancer rates in the United States are increasing, 5-year survival is only 17.6%, underscoring the importance of prevention. Physical activity has been associated with lower risk of developing liver cancer, but most studies assess physical activity only at a single point in time, often in midlife. We utilized physical activity data from 296,661 men and women in the NIH-AARP Diet and Health Study cohort to test whether physical activity patterns over the life course could elucidate the importance of timing of physical activity on liver cancer risk. We used group modeling of longitudinal data to create physical activity …


Sexually Transmitted Infections Among Hiv-Infected Individuals In The District Of Columbia And Estimated Hiv Transmission Risk: Data From The Dc Cohort, Jose Lucar, Rachel Hart, Nabil Rayeed, Arpi Terzian, Amy Weintrob, Amanda D. Castel, Debra A. Benator, Dc Cohort Executive Committee Jan 2018

Sexually Transmitted Infections Among Hiv-Infected Individuals In The District Of Columbia And Estimated Hiv Transmission Risk: Data From The Dc Cohort, Jose Lucar, Rachel Hart, Nabil Rayeed, Arpi Terzian, Amy Weintrob, Amanda D. Castel, Debra A. Benator, Dc Cohort Executive Committee

Epidemiology Faculty Publications

Background

Washington, DC, has one of the highest rates of HIV infection in the United States. Sexual intercourse is the leading mode of HIV transmission, and sexually transmitted infections (STIs) are a risk factor for HIV acquisition and transmission.

Methods

We evaluated the incidence and demographic factors associated with chlamydia, gonorrhea, and syphilis among HIV-infected persons enrolled at 13 DC Cohort sites from 2011 to 2015. Using Poisson regression, we assessed covariates of risk for incident STIs. We also examined HIV viral loads (VLs) at the time of STI diagnosis as a proxy for HIV transmission risk.

Results

Six point …


Pre- And Post-Diagnosis Physical Activity, Television Viewing, And Mortality Among Hematologic Cancer Survivors., Daniela Schmid, Gundula Behrens, Hannah Arem, Christina Hart, Wolfgang Herr, Carmen Jochem, Charles E Matthews, Michael F Leitzmann Jan 2018

Pre- And Post-Diagnosis Physical Activity, Television Viewing, And Mortality Among Hematologic Cancer Survivors., Daniela Schmid, Gundula Behrens, Hannah Arem, Christina Hart, Wolfgang Herr, Carmen Jochem, Charles E Matthews, Michael F Leitzmann

Epidemiology Faculty Publications

PURPOSE: The associations of physical activity and television (TV) viewing with mortality risk among individuals with hematologic malignancies remain unclear.

METHODS: We examined the relations of physical activity and TV viewing time before and after diagnosis with mortality among 5182 U.S. adults aged 50-71 years from the NIH-AARP Diet and Health Study cohort who survived a first primary hematologic cancer between 1995-1996 and 2011.

RESULTS: For the pre- and post-diagnosis analyses, we confirmed 2606 and 613 deaths respectively. In multivariable-adjusted Cox proportional hazard regression models, comparing high (≥4 hrs/wk) versus low (/wk) activity levels, pre-diagnosis physical activity was associated with …


Impact Of Chronic Sexual Abuse And Depression On Inflammation And Wound Healing In The Female Reproductive Tract Of Hiv-Uninfected And Hiv-Infected Women., Mimi Ghosh, Jason Daniels, Maria Pyra, Monika Juzumaite, Mariel Jais, Kerry Murphy, Tonya N Taylor, Seble Kassaye, Lorie Benning, Mardge Cohen, Kathleen Weber Jan 2018

Impact Of Chronic Sexual Abuse And Depression On Inflammation And Wound Healing In The Female Reproductive Tract Of Hiv-Uninfected And Hiv-Infected Women., Mimi Ghosh, Jason Daniels, Maria Pyra, Monika Juzumaite, Mariel Jais, Kerry Murphy, Tonya N Taylor, Seble Kassaye, Lorie Benning, Mardge Cohen, Kathleen Weber

Epidemiology Faculty Publications

Sexual violence is associated with increased risk of HIV acquisition/transmission in women. Forced sex can result in physical trauma to the reproductive tract as well as severe psychological distress. However, immuno-biological mechanisms linking sexual violence and HIV susceptibility are incompletely understood. Using the Women's Interagency HIV Study repository, a total of 77 women were selected to form 4 groups, stratified by HIV serostatus, in the following categories: 1) no sexual abuse history and low depressive symptom score (below clinically significant cut-off, scores


Colonization Density Of The Upper Respiratory Tract As A Predictor Of Pneumonia-Haemophilus Influenzae, Moraxella Catarrhalis, Staphylococcus Aureus, And Pneumocystis Jirovecii., Daniel E Park, Henry C Baggett, Stephen R C Howie, Qiyuan Shi, Nora L Watson, W Abdullah Brooks, Perch Study Group Jun 2017

Colonization Density Of The Upper Respiratory Tract As A Predictor Of Pneumonia-Haemophilus Influenzae, Moraxella Catarrhalis, Staphylococcus Aureus, And Pneumocystis Jirovecii., Daniel E Park, Henry C Baggett, Stephen R C Howie, Qiyuan Shi, Nora L Watson, W Abdullah Brooks, Perch Study Group

Epidemiology Faculty Publications

Background.

There is limited information on the association between colonization density of upper respiratory tract colonizers and pathogen-specific pneumonia. We assessed this association for Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus, and Pneumocystis jirovecii. Methods.

In 7 low- and middle-income countries, nasopharyngeal/oropharyngeal swabs from children with severe pneumonia and age-frequency matched community controls were tested using quantitative polymerase chain reaction (PCR). Differences in median colonization density were evaluated using the Wilcoxon rank-sum test. Density cutoffs were determined using receiver operating characteristic curves. Cases with a pathogen identified from lung aspirate culture or PCR, pleural fluid culture or …


Mechanistic Mathematical Models: An Underused Platform For Hpv Research, Marc Ryser, Patti Gravitt, Evan R. Myers Jun 2017

Mechanistic Mathematical Models: An Underused Platform For Hpv Research, Marc Ryser, Patti Gravitt, Evan R. Myers

Global Health Faculty Publications

Health economic modeling has become an invaluable methodology for the design and evaluation of clinical and public health interventions against the human papillomavirus (HPV) and associated diseases. At the same time, relatively little attention has been paid to a different yet complementary class of models, namely that of mechanistic mathematical models. The primary focus of mechanistic mathematical models is to better understand the intricate biologic mechanisms and dynamics of disease. Inspired by a long and successful history of mechanistic modeling in other biomedical fields, we highlight several areas of HPV research where mechanistic models have the potential to advance the …


Cancer-Specific Mortality, Cure Fraction, And Noncancer Causes Of Death Among Diffuse Large B-Cell Lymphoma Patients In The Immunochemotherapy Era., Nadia Howlader, Angela B Mariotto, Caroline Besson, Gita Suneja, Kim Robien, Naji Younes, Eric A Engels May 2017

Cancer-Specific Mortality, Cure Fraction, And Noncancer Causes Of Death Among Diffuse Large B-Cell Lymphoma Patients In The Immunochemotherapy Era., Nadia Howlader, Angela B Mariotto, Caroline Besson, Gita Suneja, Kim Robien, Naji Younes, Eric A Engels

Epidemiology Faculty Publications

BACKGROUND

Survival after the diagnosis of diffuse large B-cell lymphoma (DLBCL) has been increasing since 2002 because of improved therapies; however, long-term outcomes for these patients in the modern treatment era are still unknown.

METHODS

Using Surveillance, Epidemiology, and End Results data, this study first assessed factors associated with DLBCL-specific mortality during 2002-2012. An epidemiologic risk profile, based on clinical and demographic characteristics, was used to stratify DLBCL cases into low-, medium-, and high-risk groups. The proportions of DLBCL cases that might be considered cured in these 3 risk groups was estimated. Risks of death due to various noncancer causes …


Variables Associated With Overweight/Obesity Among African-American Women With Hypertension And/Or Diabetes, Monica A. Hamilton, Dnp, Rn, Acns-Bc Apr 2017

Variables Associated With Overweight/Obesity Among African-American Women With Hypertension And/Or Diabetes, Monica A. Hamilton, Dnp, Rn, Acns-Bc

Doctor of Nursing Practice Projects

BACKGROUND

Obesity is the second leading cause of preventable death next to tobacco use. Although it is prevalent in all populations, it disproportionately affects AA women. Overweight/obesity increases AA women’s chances of developing chronic illnesses such as diabetes, hypertension, heart disease, and decreases their life expectancy. The purpose of this study was to explore variables associated with overweight/obese AA women with hypertension and/or diabetes.

METHODS

A secondary data analysis was conducted using a descriptive-correlational design to analyze cross-sectional data obtained from the 2013 Behavioral Risk Factor Surveillance System (BRFSS). The sample consisted of AA women (n =1823). The dependent variable …


Effect Of Immediate Initiation Of Antiretroviral Therapy On Risk Of Severe Bacterial Infections In Hiv-Positive People With Cd4 Cell Counts Of More Than 500 Cells Per Μl: Secondary Outcome Results From A Randomised Controlled Trial., Jemma O'Connor, Michael J Vjecha, Andrew N Phillips, Brian Angus, David Cooper, Fred Gordin, +Several Additional Authors Mar 2017

Effect Of Immediate Initiation Of Antiretroviral Therapy On Risk Of Severe Bacterial Infections In Hiv-Positive People With Cd4 Cell Counts Of More Than 500 Cells Per Μl: Secondary Outcome Results From A Randomised Controlled Trial., Jemma O'Connor, Michael J Vjecha, Andrew N Phillips, Brian Angus, David Cooper, Fred Gordin, +Several Additional Authors

Medicine Faculty Publications

BACKGROUND: The effects of antiretroviral therapy on risk of severe bacterial infections in people with high CD4 cell counts have not been well described. In this study, we aimed to quantify the effects of immediate versus deferred ART on the risk of severe bacterial infection in people with high CD4 cell counts in a preplanned analysis of the START trial.

METHODS: The START trial was a randomised controlled trial in ART-naive HIV-positive patients with CD4 cell count of more than 500 cells per μL assigned to immediate ART or deferral until their CD4 cell counts were lower than 350 cells …


A Comparison Of The Quality Of Informed Consent For Clinical Trials Of An Experimental Hookworm Vaccine Conducted In Developed And Developing Countries., David J. Diemert, Lucas Lobato, Ashley Styczynski, Maria Zumer, Amanda Soares, Maria Flávia Gazzinelli Jan 2017

A Comparison Of The Quality Of Informed Consent For Clinical Trials Of An Experimental Hookworm Vaccine Conducted In Developed And Developing Countries., David J. Diemert, Lucas Lobato, Ashley Styczynski, Maria Zumer, Amanda Soares, Maria Flávia Gazzinelli

Microbiology, Immunology, and Tropical Medicine Faculty Publications

Informed consent is one of the principal ethical requirements of conducting clinical research, regardless of the study setting. Breaches in the quality of the informed consent process are frequently described in reference to clinical trials conducted in developing countries, due to low levels of formal education, a lack of familiarity with biomedical research, and limited access to health services in these countries. However, few studies have directly compared the quality of the informed consent process in developed and developing countries using the same tool and in similar clinical trials. This study was conducted to compare the quality of the informed …


Anti-Müllerian Hormone And Its Relationships With Subclinical Cardiovascular Disease And Renal Disease In A Longitudinal Cohort Study Of Women With Type 1 Diabetes, Catherine Kim, Yuanyuan Pan, Barbara Braffett, Valerie Arends, Michael Steffes, Hunter Wessells, Aruna V. Sarma Jan 2017

Anti-Müllerian Hormone And Its Relationships With Subclinical Cardiovascular Disease And Renal Disease In A Longitudinal Cohort Study Of Women With Type 1 Diabetes, Catherine Kim, Yuanyuan Pan, Barbara Braffett, Valerie Arends, Michael Steffes, Hunter Wessells, Aruna V. Sarma

GW Biostatistics Center

Background

Reproductive age may be a risk factor for vascular disease. Anti-Müllerian hormone (AMH) is produced by viable ovarian follicles and reflects reproductive age. We examined whether AMH concentrations were associated with markers of subclinical cardiovascular disease (CVD) and kidney disease among women with type 1 diabetes.

Methods

We performed a cross-sectional analysis of the Epidemiology of Diabetes Interventions and Complications Study. Participants included women with type 1 diabetes and ≥1 AMH measurement (n = 390). In multivariable regression models which adjusted for repeated measures, we examined the associations between AMH with CVD risk factors, estimated glomerular filtration rate, …


Perspectives On Model Forecasts Of The 2014–2015 Ebola Epidemic In West Africa: Lessons And The Way Forward, Gerardo Chowell, Cecile Viboud, Lone Simonsen, Stefano Merler, Alessandro Vespignani Jan 2017

Perspectives On Model Forecasts Of The 2014–2015 Ebola Epidemic In West Africa: Lessons And The Way Forward, Gerardo Chowell, Cecile Viboud, Lone Simonsen, Stefano Merler, Alessandro Vespignani

Global Health Faculty Publications

The unprecedented impact and modeling efforts associated with the 2014–2015 Ebola epidemic in West Africa provides a unique opportunity to document the performances and caveats of forecasting approaches used in near-real time for generating evidence and to guide policy. A number of international academic groups have developed and parameterized mathematical models of disease spread to forecast the trajectory of the outbreak. These modeling efforts often relied on limited epidemiological data to derive key transmission and severity parameters, which are needed to calibrate mechanistic models. Here, we provide a perspective on some of the challenges and lessons drawn from these efforts, …


"It Makes You Feel Like Someone Cares" Acceptability Of A Financial Incentive Intervention For Hiv Viral Suppression In The Hptn 065 (Tlc-Plus) Study., Elizabeth Greene, Allison Pack, Jill Stanton, Victoria Shelus, Elizabeth E Tolley, Jamilah Taylor, Wafaa M El Sadr, Bernard M Branson, Jason Leider, Natella Rakhmanina, Theresa Gamble Jan 2017

"It Makes You Feel Like Someone Cares" Acceptability Of A Financial Incentive Intervention For Hiv Viral Suppression In The Hptn 065 (Tlc-Plus) Study., Elizabeth Greene, Allison Pack, Jill Stanton, Victoria Shelus, Elizabeth E Tolley, Jamilah Taylor, Wafaa M El Sadr, Bernard M Branson, Jason Leider, Natella Rakhmanina, Theresa Gamble

Pediatrics Faculty Publications

BACKGROUND: HPTN 065 (TLC-Plus) evaluated the feasibility and effectiveness of providing quarterly $70 gift card financial incentives to HIV-infected patients on antiretroviral therapy (ART) to encourage ART adherence and viral suppression, and represents the largest study to-date of a financial incentive intervention for HIV viral suppression. A post-trial qualitative substudy was undertaken to examine acceptability of the financial incentives among those receiving and implementing the intervention.

METHODS: Between July and October 2013, semi-structured interviews were conducted with 72 patients and 12 investigators from 14 sites; three focus groups were conducted with 12 staff from 10 sites. Qualitative data collection elicited …


Pertussis-Associated Pneumonia In Infants And Children From Low- And Middle-Income Countries Participating In The Perch Study., Breanna Barger-Kamate, Maria Deloria Knoll, E Wangeci Kagucia, Christine Prosperi, Henry C Baggett, Daniel E. Park, +31 Additional Authors Dec 2016

Pertussis-Associated Pneumonia In Infants And Children From Low- And Middle-Income Countries Participating In The Perch Study., Breanna Barger-Kamate, Maria Deloria Knoll, E Wangeci Kagucia, Christine Prosperi, Henry C Baggett, Daniel E. Park, +31 Additional Authors

Epidemiology Faculty Publications

BACKGROUND:  Few data exist describing pertussis epidemiology among infants and children in low- and middle-income countries to guide preventive strategies.

METHODS:  Children 1-59 months of age hospitalized with World Health Organization-defined severe or very severe pneumonia in 7 African and Asian countries and similarly aged community controls were enrolled in the Pneumonia Etiology Research for Child Health study. They underwent a standardized clinical evaluation and provided nasopharyngeal and oropharyngeal swabs and induced sputum (cases only) for Bordetella pertussis polymerase chain reaction. Risk factors and pertussis-associated clinical findings were identified.

RESULTS:  Bordetella pertussis was detected in 53 of 4200 (1.3%) cases …


Analysis Of Hiv Diversity In Hiv-Infected Black Men Who Have Sex With Men (Hptn 061), Iris Chen, Gordon Chau, Jing Wang, William Clarke, Mark A. Marzinke, Manya Magnus, +14 Additional Authors Dec 2016

Analysis Of Hiv Diversity In Hiv-Infected Black Men Who Have Sex With Men (Hptn 061), Iris Chen, Gordon Chau, Jing Wang, William Clarke, Mark A. Marzinke, Manya Magnus, +14 Additional Authors

Epidemiology Faculty Publications

Background

HIV populations often diversify in response to selective pressures, such as the immune response and antiretroviral drug use. We analyzed HIV diversity in Black men who have sex with men who were enrolled in the HIV Prevention Trials Network 061 study.

Methods

A high resolution melting (HRM) diversity assay was used to measure diversity in six regions of the HIV genome: two in gag, one in pol, and three in env. HIV diversity was analyzed for 146 men who were HIV infected at study enrollment, including three with acute infection and 13 with recent infection (identified …


The Cost-Effectiveness Of Diabetes Prevention: Results From The Diabetes Prevention Program And The Diabetes Prevention Program Outcomes Study, William Herman Jan 2015

The Cost-Effectiveness Of Diabetes Prevention: Results From The Diabetes Prevention Program And The Diabetes Prevention Program Outcomes Study, William Herman

GW Biostatistics Center

Background

The Diabetes Prevention Program (DPP) was a randomized, controlled clinical trial. It demonstrated that among high-risk individuals with impaired glucose tolerance, diabetes incidence was reduced by 58 % with lifestyle intervention and 31 % with metformin compared to placebo. During the Diabetes Prevention Program Outcomes Study (DPPOS), all DPP participants were unmasked to their treatment assignments, the original lifestyle intervention group was offered additional lifestyle support, the metformin group continued metformin, and all three groups were offered a group-implemented lifestyle intervention. Over the 10 years of combined DPP/DPPOS follow-up, diabetes incidence was reduced by 34 % in the lifestyle …