Ventilatory Constraint, Breathing Pattern and Ventilatory Responses in Obese Postmenopausal Women

This study has been completed.
Sponsor:
Information provided by:
National Taiwan University Hospital
ClinicalTrials.gov Identifier:
NCT01034098
First received: December 16, 2009
Last updated: NA
Last verified: December 2009
History: No changes posted
  Purpose

The purpose of this study was to examine the dynamic lung volumes in obese post-menopausal women (without hormone replacement therapy) during exercise and their correlations with dyspnea.


Condition
Obesity
Postmenopausal Women

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Cross-Sectional
Official Title: Ventilatory Constraint, Breathing Pattern and Ventilatory Responses in Obese Postmenopausal Women

Resource links provided by NLM:


Further study details as provided by National Taiwan University Hospital:

Primary Outcome Measures:
  • Dynamic lung volume: end-expiratory lung volume (EELV), end-inspiratory lung volume (EILV) [ Time Frame: At least 1 year post-menopause ] [ Designated as safety issue: Yes ]

Secondary Outcome Measures:
  • Pulmonary function [ Time Frame: At least 1 year post-menopause ] [ Designated as safety issue: Yes ]
  • Breathing pattern [ Time Frame: At least 1 year post-menopause ] [ Designated as safety issue: Yes ]
  • Ventilatory response [ Time Frame: At least 1 year post-menopause ] [ Designated as safety issue: Yes ]
  • Visual analog scale (VAS) for dyspnea and leg fatigue [ Time Frame: At least 1 year post-menopause ] [ Designated as safety issue: Yes ]

Enrollment: 50
Study Start Date: December 2005
Study Completion Date: April 2007
Primary Completion Date: April 2007 (Final data collection date for primary outcome measure)
Groups/Cohorts
Post-menopausal women
Post-menopausal women (without hormone replacement therapy)

Detailed Description:

Obesity-related changes in lung volumes have shown to affect breathing mechanisms. During exercise, altered breathing mechanisms increase potential for expiratory flow limitation and compromise exercise capacity. Estrogen and progesterone are potent respiratory stimulants, and their effects in the physiologic regulation of breathing are down-regulated after menopause. Therefore, we theorized that the combined obesity and reduced sex hormone levels after menopause work as a double jeopardy to cause mechanical ventilatory constraint which aggravates dyspnea sensation during exercise, and thus a reduction in exercise capacity. The purpose of this study was to exam the dynamic lung volumes in obese post-menopausal women (without hormone replacement therapy) during exercise and their correlations with dyspnea.

From doctoral referral and advertisement, 24 obese (BMI ≧ 27 kg/m2) and 26 lean post-menopausal women were recruited for the study. Pulmonary function and body composition were measured at rest. A maximal flow volume loop (MFVL) was obtained at baseline. All subjects then performed an incremental exercise test on a cycle ergometer with workload increasing 25 watts every 3 min. During exercise, at each workload, the tidal exercise FV loops were obtained and an inspiratory capacity (IC) maneuver was conducted to assess changes in end-expiratory lung volume (EELV) and end inspiratory lung volume (EILV). Dyspnea and leg fatigue were assessed using the Borg scale. Analysis of variance with repeated measurements was used to test the significance of the mean differences between the two groups during exercise. Linear regression analysis was used to determine whether changes in dynamic lung volumes during exercise were related to changes in Borg scores. Statistical significance was established at p<0.05.

  Eligibility

Ages Eligible for Study:   50 Years to 69 Years
Genders Eligible for Study:   Female
Accepts Healthy Volunteers:   Yes
Sampling Method:   Probability Sample
Study Population

Postmenopausal women (for at least 1 year) who aged below 69 y/o without hormone replacement therapy

Criteria

Inclusion Criteria:

  • Postmenopausal women (for at least 1 year)
  • Age below 69 y/o
  • Not receiving hormone replacement therapy

Exclusion Criteria:

  • Cardiopulmonary disease
  • Musculoskeletal disease affecting results of maximal exercise test
  Contacts and Locations
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, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT01034098

Locations
Taiwan
School and Graduate Institute of Physical Therapy, National Taiwan University
Taipei, Taiwan
Sponsors and Collaborators
National Taiwan University Hospital
Investigators
Principal Investigator: Li-Ying Wang, Ph.D. School and Graduate Institute of Physical Therapy, National Taiwan University
  More Information

No publications provided

Responsible Party: Li-Ying Wang, School and Graduate Institute of Physical Therapy, National Taiwan University
ClinicalTrials.gov Identifier: NCT01034098     History of Changes
Other Study ID Numbers: 9461701144
Study First Received: December 16, 2009
Last Updated: December 16, 2009
Health Authority: Taiwan: Department of Health

Keywords provided by National Taiwan University Hospital:
Obesity
Postmenopausal women
Mechanical ventilatory constraints
Dynamic lung volume
Expiratory flow limitation

Additional relevant MeSH terms:
Obesity
Body Weight
Nutrition Disorders
Overnutrition
Overweight
Signs and Symptoms

ClinicalTrials.gov processed this record on October 20, 2014