Obesity Clinical Trials

Americans commonly consume excess amounts of dietary fructose. Added fructose has been shown to have an adverse impact on metabolic health, including increased insulin resistance and type 2 diabetes (T2D) risk. However, the mechanisms that link dietary fructose and metabolic health are poorly understood. Malabsorption or incomplete metabolism of fructose in the small intestine is common in the population. Excess fructose reaches the colon where it may change the structure and function of the gut microbiome, alter bacterial metabolites and trigger inflammatory responses impacting T2D risk. To elucidate whether commonly consumed levels of dietary fructose influence metabolic outcomes through altering the gut microbiome, the research team will randomize 30 participants to a controlled cross-over dietary intervention, in which the participants will consume 12-day isocaloric, added fructose or glucose diets (25% of total calories) separated by a 10-day controlled diet washout period. The research team aims to: 1. Determine the relationships between high fructose consumption, the gut microbiome and metabolic risk. 2. Characterize the causal role(s) that fructose-induced alterations to the gut microbiome have on metabolic risk using a germ-free mouse model. The research team will measure 1) microbiota community structure and function via metagenomic sequencing of stool, 2) fecal metabolites via targeted and untargeted metabolomics, 3) anthropometrics, 4) insulin resistance, serum markers of T2D risk and inflammatory cytokines, 5) fecal microbial carbohydrate oxidation capacity and 6) liver fat via MRI elastography. The research team will use novel statistical approaches, including Distributed Lag Modeling, to understand the complex relationships between diet, the microbiome, metabolites and health outcomes. The research team will then conduct controlled dietary interventions and fecal microbiome transplantation studies in germ-free mice. Donor fecal samples from human participants in both the glucose and fructose arms of the clinical intervention will be transplanted into germ-free and colonized mice to establish a causal relationship between fructose-induced changes to the gut microbiome, liver fat and metabolic and inflammatory changes known to increase risk for T2D. The research team aims to comprehensively assess the structural and functional changes to the gut microbiome brought about by a high fructose diet. Determining the impact of excess fructose on the microbiome will help identify novel means by which fructose contributes to metabolic disease risk. In addition to identifying strategies to improve metabolic health in adults, data from this proposal could help inform targeted approaches to mitigate future disease risk in vulnerable populations that consume high levels of fructose, such as children. Read Less

The researchers will conduct 'Taxi ROADmAP (Realizing Optimization Around Diet And Physical activity)', which also utilizes MOST, and the same 4 obesity intervention components as in SANOS, but targets the overweight/obesity crisis in another at-risk, low socioeconomic status (SES) population, taxi and for-hire vehicle (FHV) drivers (Lyft, Uber, etc.). ROADMAP also utilizes an effectiveness- implementation hybrid type 1 design. Hybrid trials, which blend effectiveness and implementation studies, can lead to more rapid translational uptake and more effective implementation. Taxi and FHV drivers are a growing, multilingual, hard-to-reach, predominantly immigrant and minority essential worker population. There are over 750,000 licensed taxi and FHV drivers in in the U.S. and over 185,000 in New York City (NYC). They have higher rates of overweight/obese range body mass index (BMI) than New Yorkers in general (77% vs 56%) and have high rates of elevated waist circumference, sedentary behavior, poor diets, and health care services underutilization. ROADmAP will test 4 evidence- and theory-based (Social Cognitive Theory \[SCT\]) behavior change intervention components. We will use MOST to identify which of the 4 components contribute most significantly and cost-effectively to weight loss among NYC drivers recruited at workplace health fairs (HFs) and virtually. Objectives are to apply MOST to design an optimized version of a scalable, lifestyle intervention for taxi/FHV drivers, and then to conduct a mixed methods multistakeholder process evaluation to facilitate widespread intervention implementation. Read Less

The proposed 6-month pilot Sequential Multiple Assignment Randomize Trial (SMART) has two aims. The first and primary aim is to determine the feasibility of conducting a full-scale SMART to compare weight-focused (i.e., weight loss) and weight-neutral (i.e., weight loss is not an explicit goal) adaptive biobehavioral interventions for improving cardiometabolic health in Black adults with overweight or obesity (BMI ≥27 kg/m2) plus at least one weight-related cardiometabolic condition (high blood pressure, prediabetes or diabetes, and/or high cholesterol). Biobehavioral interventions are treatment strategies that combine lifestyle-based behavioral interventions such as eating a healthy diet and exercise with medications. In this study, participants will be randomly assigned to receive either weight-focused or weight-neutral health coaching for 7 weeks. At week 8, participants will be identified as either "responders" or "nonresponders" to the initial interventions. The threshold for response in the weight-focused condition is greater than or equal to 3% weight loss. The threshold for response in the weight-neutral condition is engaging in greater than or equal to 150 minutes of moderate physical activity for the 7 days prior to the week 8 study visit. Responders to the initial interventions will continue with health coaching on a biweekly basis for weeks 9-26 of the intervention. Nonresponders will be re-randomized to either intensify the lifestyle-based intervention by receiving a membership to the YMCA and enrolling in group fitness classes or augmenting the health coaching with enhanced medical management in partnership with their established primary care provider. The second aim is to use clinical data from the pilot SMART to estimate treatment effects and the between-person variability in these effects. Because this is a pilot study, these estimates will not be used to make comparisons or draw conclusions on the comparative effectiveness of intervention conditions. Rather, these data will be used to generate preliminary effect sizes that can be used to estimate the sample size required for a full-scale trial. Clinical trial feasibility data will be collected on an ongoing basis throughout the study and clinical data will be collected prior to initiating the intervention (baseline) and at week 8 (response visit) and week 26 (post-intervention visit). Read Less

This study will compare the effectiveness of behavioral and pharmacologic treatment, alone and combined, for improvements in weight loss, cardiovascular risk factors, and psychosocial functioning following metabolic and bariatric surgery. Read Less

The purpose of this study is to examine the hypothesize that 4 weeks of sympathetic nerve activity (SNA) inhibition (oral clonidine) will cause a significant reduction in circulating blood concentrations and endothelial cell expression of inflammatory markers (e.g., TNF-α, IL-6). Our study is a prospective study using a randomized, double-blinded design to test 4 weeks of SNA blockade (oral clonidine) compared with a BP-lowering control condition (diuretic, hydrochlorothiazide) or a placebo. Read Less

The study is testing a new study medicine to treat people living with overweight or obesity. The aim of this study is to see if the medicine is safe, how it works in your body, and what your body does to the study medicine. Participants will either get the study medicine or placebo (a "dummy medicine" similar to the study medicine but without active ingredients) given as an injection under your skin. Which treatment the participants get is decided by chance. The study medicine is a potential new medicine which cannot be prescribed by doctors. Read Less

In addition to chronically elevated MSNA, there is a growing recognition that hypertension in states of insulin resistance and obesity may also be attributed to an increased vascular sensitivity to MSNA (1, 2, 13, 36-38). To study this phenomenon, we quantify vascular sensitivity to MSNA using an innovative, moment-to-moment assessment of the blood pressure response following individual bursts of muscle sympathetic nerve activity (MSNA), (10, 11, 34, 37). This approach is termed 'sympathetic-vascular transduction (SVT).' We will examine the hypothesis that SVT is exaggerated in obesity and insulin resistance and is attenuated by suppression of oxidative stress. Oxidative stress is the overabundance of reactive oxygen species and is another hallmark of hypertension, obesity, and insulin resistance. Oxidative stress can be safely reduced via intravenous infusion of ascorbic acid (Vit C) (4, 28). Therefore, we will use a randomized, double-blinded, placebo-controlled approach to test the hypothesis that elevated SVT will be attenuated by suppression of oxidative stress via ascorbic acid I.V. infusion compared with saline I.V. infusion (placebo) in obese adults with insulin resistance. Our study will identify a unique mechanism that can be targeted to reduce the excessively high prevalence of hypertension and risk for CVD in obesity and insulin resistance. Read Less

This proposal is designed to (1) establish the feasibility of a research strategy for discovering ethnic differences in the frequency of genotypes in patients after bariatric surgery and (2) perform a preliminary evaluation of this research strategy. Our goal is to identify genetic factors that may influence the success of various surgical weight loss interventions and determine whether these factors are associated with specific patient populations. Read Less

This study is a pilot open label crossover trial to assess the feasibility and acceptability of reducing ultra- processed foods (UPF) in a personalized manner from the diets of patients with major depressive disorder who eat a large percentage of UPF. Read Less

The goal of this clinical trial is to determine the physiological basis for the differences in weight regain among adults (25-59 years old) with obesity following participation in a behavioral weight loss program. Eligible participants will undergo a baseline evaluation after which they will enter an up to 20 week behavioral weight loss program with the goal of losing at least 7 percent of their baseline weight within 37 weeks. Participants who meet the weight loss goal will be asked to remain weight stable for 2 weeks after which they will undergo a clinical examination. They will then be observed for 1 year during which they will undergo 2 additional clinical examinations, one 4 months after completing the weight loss program, and the other 12 months after completing the weight loss program. Read Less

The purpose of the present pilot is to evaluate the outcomes of adding a patient coach to support the Optimal Health Weight and Lifestyle (OHWL) Clinic plan developed by PI Dewar, specifically to address barriers and facilitators of adherence to the plan. This will be accomplished via a coach who is not embedded in clinic care and is supported by pilot research funds. Evaluation of the coach activities, conducted by research personnel, will include compiling data from the electronic health record, a short set of patient report and performance measures, and qualitative interviews. Read Less

Background: Time restricted eating (TRE) is a form of fasting in which a person eats only during a set window of time, which is usually between 4 and 10 hours each day. Researchers want to know more about how TRE may affect health. Objective: To learn how TRE affects women with different body sizes. Eligibility: Healthy women aged 18 to 50 years. Design: Participants will have 2 visits: 1 screening visit and one 5-day stay in the clinic. Participants will fast before both visits. They will have a physical exam with blood tests. They will talk to a nutritionist about the foods they eat. They will lay under a clear hood for up to 45 minutes during a test that measures how many calories they burn while resting. Participants will keep a food diary for up to 7 days before their clinic stay. They will apply a continuous glucose monitor the day before they go to the clinic. This is a device that attaches to the skin of the stomach. They will wear this device throughout their clinic stay. All meals will be provided during the clinic stay. Participants will follow TRE on 3 days. They will answer survey questions and have tests during their stay, including: * DXA (dual energy X-ray absorptiometry) scan. Participants will lie on a padded table. Their body will be scanned to measure how much muscle, bone, fat, and other tissues they have. * Stable isotope tracer study. Small amounts of sugar and other substances will be given through a tube attached to a needle inserted into a vein in the arm. Blood samples will be collected. Read Less