Effects of Daily Low Oxygen Exposure on Weight Status, Body Composition, and Metabolic Health
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 入组人数
- 60
- 试验地点
- 1
- 主要终点
- Change in body weight
研究概览
简要总结
The objective of the proposed double-blind, parallel-arm, randomized clinical trial is to evaluate changes in body weight and composition, assess determinants of energy balance (intake and expenditure), and measure modulators of energy balance, following 8 wk of calorie restriction (-500 kcal/d) in combination with either overnight exposure to normobaric hypoxia (8 h/night, 15% FiO2, ~2640 m) or normoxia (8 h/night, 21% FiO2), using a commercially available, in-home tent system, in adults with obesity.
详细描述
Obesity and associated metabolic conditions are a significant public health burden, costing the U.S. ~$150 billion annually. Obesity is both a disease, affecting 1 in 3 Americans, and a risk factor for other chronic diseases, such as cardiovascular disease, type 2 diabetes, and 13 forms of cancers. Diet and exercise are the cornerstone of obesity prevention and treatment. However, a considerable number of individuals are non-responsive to existing weight-loss interventions and obesity rates continue to rise. Therefore, non-conventional approaches are needed to supplement current weight-loss strategies. Daily exposure to low-oxygen conditions may aid in current weight- loss strategies. Moderate (1500-3500 m) and higher (≥ 3500 m) altitude environments are naturally hypoxic due to the lower atmospheric pressure (for reference, Denver, CO is ~1600 m and Mt. Hood in Oregon is ~3500 m). Studies show that sea-level natives exposed to moderate- or high- altitude continuously for 5 or more days lose weight, which is a consequence of prolonged reductions in blood and tissue oxygenation that lead to increased energy expenditure and decreased appetite. However, implementation of hypoxia as a means for weight loss has been limited, to date, by the logistical constraints of traveling to remote locations or access to an altitude chamber. A safe, less expensive, and more logistically feasible alternative is the use of commercially available, low-oxygen systems at sea level, which create a normobaric hypoxic environment. Whether in-home, overnight, normobaric hypoxic exposure, compared to normobaric normoxic exposure, promotes body mass loss in adults with obesity remains unknown. Furthermore, determinants of energy balance, including energy intake and expenditure, and their relative contribution to normobaric hypoxia-induced weight loss have not been investigated. The objective of the proposed double-blind, parallel-arm, randomized clinical trial is to evaluate changes in body weight and composition, assess determinants of energy balance (intake and expenditure), and measure modulators of energy balance, following 8 wk of calorie restriction (-500 kcal/d) in combination with either overnight exposure to normobaric hypoxia (8 h/night, 15% FiO2, ~2640 m) or normoxia (8 h/night, 21% FiO2), using a commercially available, in-home tent system, in adults with obesity. Chronic (8 weeks), overnight (8 hours/night) low oxygen exposure may provide a non-conventional approach to supplement current weight-loss strategies, inform new strategies to accelerate weight loss, aid long-term weight management efforts, and benefit metabolic health in individuals with obesity.
研究设计
- 研究类型
- Interventional
- 分配方式
- Randomized
- 干预模型
- Parallel
- 主要目的
- Treatment
- 盲法
- Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
入排标准
- 年龄范围
- 22 Years 至 65 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 是
入选标准
- •Obese (BMI between 30-39.9 kg/m2)
- •Born at altitudes below 2,100 meters (~7,000 feet)
- •Currently residing in Tallahassee, Florida or surrounding area
- •Completed a full FDA authorized or approved COVID-19 vaccination series at least 14 days before any in-person human research activity.
- •Not taking any medication(s) that interfere with oxygen delivery/transport for 4 weeks prior to and throughout the entire study (e.g., includes sedatives, sleeping aids, tranquilizers and/or any medication that depresses ventilation, diuretics, alpha and beta blockers).
- •Willing to refrain from smoking, vaping, chewing tobacco, and dietary supplement use throughout the entire study.
- •Willing to have a hypoxic tent set-up in their home and spend 8 consecutive hours per night in the tent for 8 weeks
- •Lives with a family member, partner/spouse, or roommate who can hear and respond in the unlikely event that the blood oxygen, air oxygen, or air carbon dioxide monitoring alarm would sound.
排除标准
- •Living in areas that are more than 1,200 m (~4,000 feet), or have traveled to areas that are more than 1,200 m for five days or more within the last 2 months
- •Individuals who have not completed a full FDA authorized or approved COVID-19 vaccination series at least 14 days before any in-person human research activity.
- •Cardiovascular abnormalities, gastrointestinal disorders, or any condition that interferes with oxygen delivery/transport (e.g., kidney disease, cardiovascular disease, etc.)
- •Oxygen saturation < 95% while awake or oxygen saturation dips below 88% for a total of ≥ 10 min overnight in normoxic conditions
- •Evidence of apnea or other sleeping disorders
- •Evidence of prior high-altitude pulmonary edema (HAPE) or high-altitude cerebral edema (HACE) diagnosis
- •Diagnosis or family history of sickle cell anemia/trait
- •Hematocrit <42% for males, <36% for females
- •Hemoglobin <13 g/dL for males, <12 g/dL for females
- •Blood donation within 8 weeks of beginning the study
- •Present condition of alcoholism, anabolic steroids, or other substance abuse issues
- •Women who are pregnant, lactating, planning to become pregnant, or who have had an irregular menstrual cycle in the past 6 mo.
- •Weight gain or loss > 10% of body weight during the past 6 months
- •Adults unable to consent
研究组 & 干预措施
Normobaric normoxia (NN)
8 weeks of overnight exposure (8 hrs/night) to NN conditions (~21% oxygen; sea level) using a commercially available tent and generator system (Hypoxico, Inc., New York, NY).
干预措施: Normobaric normoxia (NN) (Other)
Normobaric hypoxia (NH)
8 weeks of overnight exposure (8 hrs/night) to NH conditions (~15% oxygen; achieved with nitrogen dilution, equivalent to ~8500 feet elevation) using a commercially available tent and generator system (Hypoxico, Inc., New York, NY).
干预措施: Normobaric hypoxia (NH) (Other)
结局指标
主要结局
Change in body weight
时间窗: 10 weeks (70 days)
Body weight will be measured during the baseline weight maintenance phase (days -14 to 0) and each morning during the study (days 1 to 56) following an overnight fast and morning void, using a calibrated digital scale provided to participants to use at home (A\&D Medical wireless weight scale UC-352BLE, San Jose, CA). Change in body weight will be calculated as: body weight on day 56 - baseline body weight (average of days -14 to 0).
次要结局
- Resting metabolic rate(Days 0 and 56)
- Blood volume(Days -7 and 49)
- Total daily energy expenditure (TDEE)(Days -7 to 0 and 49-56)
- Heart rate variability(10 weeks (70 days))
- Urinary epinephrine(Days -1, 13, and 55)
- Urinary dopamine(Days -1, 13, and 55)
- Fasting blood pressure(Days -7 and 49)
- 4-compartment body composition using DEXA and deuterium dilution(Days -7 and 49)
- Waist circumference(Days -7 and 49)
- Resting substrate oxidation(Days 0 and 56)
- Overnight oxygen saturation (wrist-worn device)(10 weeks (70 days))
- Plasma insulin concentrations(Days 0 and 56)
- Whole-body insulin sensitivity index(Days 0 and 56)
- Thermic effect of glucose(Days 0 and 56)
- 24-hour glucose variability(Days -14-0, 1-14, and 42-56)
- Fasting measures of iron status(Days 0 and 56)
- Barrier Questionnaire(Day 56)
- Ad libitum energy intake(Days 0 and 56)
- Prevalence of acute mountain sickness(Days 0-7, 14, 21, 28, 35, 42, and 56)
- Subjective sleep quality(Days -7-0, 1-14, and 49-56)
- Subjective appetite measures(Days 0 and 56)
- Plasma glucose concentrations(Days 0 and 56)
- 24-hour continuous glucose concentrations(Days -14-0, 1-14, and 42-56)
- Change in body weight(4 weeks after intervention ends)
- Overnight oxygen saturation (index finger pulse oximetry)(10 weeks (70 days))
- Urinary norepinephrine(Days -1, 13, and 55)
- Assessment of sleep(10 weeks (70 days))
- Pittsburgh Sleep Quality Index(Days -1, 14, and 56)
- Psychosocial Factors(Days 0, 14, and 56)
- Heart rate variability(Days 0 and 56)
研究者
Claire Berryman
Assistant Professor
Pennington Biomedical Research Center