Try the modernized ClinicalTrials.gov beta website. Learn more about the modernization effort.
Working…
ClinicalTrials.gov
ClinicalTrials.gov Menu

Effects of Obesity in the Aged

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details.
 
ClinicalTrials.gov Identifier: NCT05028309
Recruitment Status : Recruiting
First Posted : August 31, 2021
Last Update Posted : November 24, 2021
Sponsor:
Information provided by (Responsible Party):
Tony Babb, University of Texas Southwestern Medical Center

Brief Summary:

The overall objective of this application is to investigate the effects of obesity on lung function, exercise tolerance, and DOE in older obese adults as compared with older adults without obesity, using a novel probe for mechanically unloading the thorax at rest and during exercise. The investigators will use 1) continuous negative cuirass pressure, and 2) assisted biphasic cuirass ventilation to decrease obesity-related effects in older obese adults. Our approach will be to examine respiratory function, exercise tolerance, and DOE with and without mechanical unloading in older obese men and women (65-75 yr), including those with respiratory symptoms (defined by a score of 1 or 2 on the modified Medical Research Council Dyspnea Scale), as compared with older adults without obesity.

Specific Aims: The investigators will test the following hypotheses in older adults with and without obesity:

Aim 1) Obesity will decrease respiratory function but to a greater extent in older obese adults with respiratory symptoms, (as evidenced by altered pulmonary function and breathing mechanics at rest); Aim 2) Obesity will decrease exercise tolerance (as evidenced by peak V•O2 in ml/min/kg, i.e., physical fitness), but not cardiorespiratory fitness (as evidenced by peak V•O2 in % of predicted based on ideal body wt), except in older obese adults with respiratory symptoms where both may be reduced during graded cycle ergometry.

Aim 3) Obesity will increase DOE but to a greater extent in older obese adults with respiratory symptoms as evidenced by increased ratings of perceived breathlessness (sensory & affective dimensions) during exercise.

Aim 4) Mechanical unloading of the thorax will improve respiratory function, submaximal exercise tolerance, and DOE in older obese adults, but to a greater extent in older obese adults with respiratory symptoms.


Condition or disease
Obesity Aging

Show Show detailed description

Layout table for study information
Study Type : Observational
Estimated Enrollment : 72 participants
Observational Model: Cohort
Time Perspective: Prospective
Official Title: Effects of Obesity in the Aged
Actual Study Start Date : November 24, 2021
Estimated Primary Completion Date : July 31, 2025
Estimated Study Completion Date : July 31, 2025

Group/Cohort
Older Nonobese Men
Older nonobese men defined by percent body fat 15≤ %bodyfat ≤ 27.
Older Nonobese Women
Older nonobese women defined by percent body fat 20 ≤ %bodyfat ≤ 30.
Older Obese Men
Older obese men defined by percent body fat 30 ≤ %bodyfat ≤ 50 and have a score of zero on the mMRC ("I only get breathless with strenuous exercise").
Older Obese Women
older obese women defined by percent body fat 35 ≤ %bodyfat ≤ 55 and have a score of zero on the mMRC ("I only get breathless with strenuous exercise").
Older Obese Men + Respiratory Symptoms
Older obese men defined by percent body fat 30 ≤ %bodyfat ≤ 50 with respiratory symptoms (defined as individuals with a modified Medical Council Dyspnea Scale, mMRC, score of 1 ["I get short of breath when hurrying on the level or walking up a slight hill"] or 2 [I walk slower than people of the same age on the level because of breathlessness or have to stop for breath when walking at my own pace on the level"]).
Older Obese Women + Respiratory Symptoms
Older obese women defined by percent body fat 35 ≤ %bodyfat ≤ 55 with respiratory symptoms (defined as individuals with a modified Medical Council Dyspnea Scale, mMRC, score of 1 ["I get short of breath when hurrying on the level or walking up a slight hill"] or 2 [I walk slower than people of the same age on the level because of breathlessness or have to stop for breath when walking at my own pace on the level"]).



Primary Outcome Measures :
  1. Change in Pulmonary Function: Lung Volumes [ Time Frame: Outcome measures will be assessed within 24-48hrs after completion of each study condition (baseline, control, continuous, and dynamic) ]
    Pulmonary function is comprised of several physiological variables but this study will primarily measure Lung Volume: FRC (liters) and TLC (liters)

  2. Change in Exercise Tolerance - Peak VO2 [ Time Frame: Outcome measures will be assessed within 24-48hrs after completion of each study condition (baseline, control, continuous, and dynamic). ]
    Exercise Tolerance is represented by several physiological variables but the primary variable is Maximal oxygen uptake (L/min and percent predicted)

  3. Change in Dyspnea on Exertion [ Time Frame: Outcome measures will be assessed within 24-48hrs after completion of each study condition (baseline, control, continuous, and dynamic). ]
    Dyspnea on Exertion is represented using the Borg Scale which provides Ratings of Perceived Breathlessness (RPB) during constant load exercise cycling. The Borg Scale measures from 0-10, where 0 = no breathlessness and 10 = maximal breathlessness.

  4. Changes in PANAS Questionnaire [ Time Frame: Outcome measures will be assessed within 24-48hrs after completion of each study condition (baseline, control, continuous, and dynamic). ]
    Positive and Negative Affect Schedule. This scale consists of a number of words that describe different feelings and emotions.

  5. Modified Medical Research Council Dyspnea Scale (mMRC Dyspnea Scale) [ Time Frame: Outcome measures will be assessed immediately after completion of mMRC questionnaire (during study visit 2) ]
    Investigate the qualities of respiratory sensations (e.g., "effort of breathing", "breathing heavy", "breathing shallow") during exercise before and after mechanical unloading of the chest wall

  6. Dyspnoea-12 [ Time Frame: Outcome measures will be assessed immediately after completion of Dyspnoea-12 questionnaire (during study visit 2) ]
    This questionnaire is designed to help us learn more about how their breathing is troubling them.

  7. ASI [ Time Frame: Outcome measures will be assessed immediately after completion of ASI questionnaire (during study visit 2) ]
    The Anxiety Sensitivity Index (ASI) is a 16 item scale containing items specifying different concerns someone could have regarding their anxiety.

  8. HADS [ Time Frame: Outcome measures will be assessed immediately after completion of HADS questionnaire (during study visit 2) ]
    HADS (Hospital Anxiety and Depression Scale) aims to measure symptoms of anxiety (HADS Anxiety) and depression (HADS Depression). HADS score: 0-7 = normal; 8-10 = mild; 11-14 = moderate; 15-21 = severe

  9. SDS-MC [ Time Frame: Outcome measures will be assessed immediately after completion of MC-SDS questionnaire (during study visit 2) ]
    The Marlowe-Crowne Social Desirability Scale (MC-SDS) is a 33-item self-report questionnaire that assesses whether or not respondents are concerned with social approval.

  10. IPAQ [ Time Frame: Outcome measures will be assessed immediately after completion of IPAQ questionnaire (during study visit 2) ]
    International Physical Activity Questionnaires (IPAQ) is a 27-item self-reported measure of physical activity

  11. WSQ [ Time Frame: Outcome measures will be assessed immediately after completion of WSQ questionnaire (during study visit 2) ]
    Workforce Sitting Questionnaire (WSQ) is to estimate how much time they usually spend sitting in each of the following activities on a working day and a non-working day.

  12. SF-12 [ Time Frame: Outcome measures will be assessed immediately after completion of SF-12 questionnaire (during study visit 2) ]
    SF-12 is a health-related quality-of-life questionnaire


Secondary Outcome Measures :
  1. Changes in forced vital capacity (FVC) [ Time Frame: Outcome measures will be assessed within 24-48hrs after completion of each study condition (baseline, control, continuous, and dynamic) ]
    FVC is the total amount of air (liters) exhaled during the forced expiratory volume (FEV) lung function test during spirometry.

  2. Changes in forced expiratory volume (FEV) [ Time Frame: Outcome measures will be assessed within 24-48hrs after completion of each study condition (baseline, control, continuous, and dynamic) ]
    FEV is the amount of air (liters) a person can exhale during a forced breath. The amount of air exhaled is measured during the a lung function test during spirometry.

  3. Changes in forced expiratory volume in 1 second (FEV1) [ Time Frame: Outcome measures will be assessed within 24-48hrs after completion of each study condition (baseline, control, continuous, and dynamic) ]
    FEV1 is the maximum amount of air (liters) that the a participant can forcibly expel during the first second following maximal inhalation. The FEV1 is measured during the a lung function test during spirometry.

  4. Changes in FEV1/FVC Ratio [ Time Frame: Outcome measures will be assessed within 24-48hrs after completion of each study condition (baseline, control, continuous, and dynamic) ]
    The FEV1/FVC (%) ratio is a calculation often used to determine the presence of obstructive or restrictive lung diseases such as chronic obstructive pulmonary disease (COPD).

  5. Changes is peak flow [ Time Frame: ChangesOutcome measures will be assessed within 24-48hrs after completion of each study condition (baseline, control, continuous, and dynamic) between conditions (visits 3-6) compared to baseline between cohorts ]
    Peak flow measurement is done with a peak flow meter. It measures the maximum (or peak) speed at which air (liters/sec) can be blown out of the lungs. This measurement provides a general idea of how narrow the lung airways are. It can also show how much the airways are changing over time if measured each day.

  6. Pulmonary Function: Diffusing Capacity [ Time Frame: Outcome measures will be assessed within 24-48hrs after completion of each study condition (baseline, control, continuous, and dynamic) ]
    Diffusing Capacity: Diffusing capacity of lung for carbon monoxide(DLco) (ml/mmHg/min)

  7. Exercise Tolerance: Work Rate [ Time Frame: Outcome measures will be assessed within 24-48hrs after completion of each study condition (baseline, control, continuous, and dynamic) ]
    Associated variables such as work rate (W)

  8. Exercise Tolerance: Minute Ventilation [ Time Frame: Outcome measures will be assessed within 24-48hrs after completion of each study condition (baseline, control, continuous, and dynamic) ]
    Associated variables such as pulmonary ventilation (L/min)

  9. Exercise Tolerance: Operational Lung Volumes [ Time Frame: Outcome measures will be assessed within 24-48hrs after completion of each study condition (baseline, control, continuous, and dynamic) ]
    Associated variables such as operational lung volumes (EELV and EILV as a % of TLC)



Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.


Layout table for eligibility information
Ages Eligible for Study:   65 Years to 75 Years   (Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Sampling Method:   Non-Probability Sample
Study Population
Volunteers included in the study will be men and women between 65-75 years of all racial and ethnic origins. Participants will be in good physical and mental health (by medical history and screening) and meet inclusion criteria.
Criteria

Inclusion Criteria:

  • Otherwise healthy older adults 65-75 years of age with normal lung function; men 30< %body fat ≤50 and women 35< %body fat ≤55; and ability to perform pulmonary and exercise test. Other inclusion criteria include the following:
  • Nonsmokers who have no history of smoking
  • No personal history of significant mental illness
  • No weight loss dietary restrictions
  • No current or past history of significant substance or alcohol abuse
  • No history, evidence, or uncontrolled symptoms of heart disease
  • No history of uncontrolled hypertension
  • No current medications that may interfere with exercise capacity
  • No recent history or indication of asthma
  • No musculoskeletal abnormality that would preclude exercise
  • No documented sleep disorders (e.g., SDB &/or sleep apnea)
  • No serious health conditions that would preclude study goals or participation in exercise (per PI & medical staff & preliminary or follow up testing; including significant other diseases, occult asthma, prior surgeries-especial lung or abdominal, or history of chemotherapy that could affect lung or heart function)
  • No metabolic disorders (e.g., diabetes).
  • Only postmenopausal women will be included.
  • Women on hormone replacement therapy will be allowed to participate if the dosage remains similar during the entire protocol.

Exclusion Criteria:

  • Volunteers with a mMRC score of 3 or 4 will be excluded due to likeliness of underlying disease.
  • Individuals participating in regular vigorous conditioning exercise such as running, jogging, aerobics, cycling, or swimming more than two times per week will be excluded. However, if subjects have an exceedingly high exercise capacity (greater than 2 SD of predicted), they will be excluded.
  • Maximal cycle ergometry test will be used to determine if further participation in testing is appropriate for the participant (e.g., normal exercise test, exclude presence of provokable ECG changes suggestive of heart disease, or dangerous arrhythmias or exercise induced hypertension or bronchoconstriction. If the participant develops an abnormal ECG or shows other signs of exercise intolerance or if signs of cardiovascular disease are noted during the exercise test, it will be terminated and the participant will be referred to their personal physician for further evaluation (see DMSP).
  • Premenopausal women will be excluded.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT05028309


Contacts
Layout table for location contacts
Contact: Research Nurse 214-345-6574 IEEMLung@TexasHealth.org
Contact: Jorge Granados, Ph.D. 214-345-6503 JorgeGranados@TexasHealth.org

Locations
Layout table for location information
United States, Texas
Institute for Exercise and Environmental Medicine, UT Southwestern and Texas Health Resources Recruiting
Dallas, Texas, United States, 75231
Contact: Raksa Moran, BSN    214-345-6574    IEEMLung@texashealth.org   
Sponsors and Collaborators
University of Texas Southwestern Medical Center
Investigators
Layout table for investigator information
Principal Investigator: Tony G Babb, Ph.D. UT Southwestern Medical Center
Layout table for additonal information
Responsible Party: Tony Babb, PROFESSOR, Cardiopulmonary Laboratory Director, Effie and Wofford Cain Chair in Cardiopulmonary Research, Institute of Exercise and Environmental Medicine, Division of Pulmonary and Critical Care Medicine, University of Texas Southwestern Medical Center
ClinicalTrials.gov Identifier: NCT05028309    
Other Study ID Numbers: STU-122010-108
First Posted: August 31, 2021    Key Record Dates
Last Update Posted: November 24, 2021
Last Verified: November 2021

Layout table for additional information
Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No
Additional relevant MeSH terms:
Layout table for MeSH terms
Obesity
Overnutrition
Nutrition Disorders
Overweight
Body Weight