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Factors Associated With Obesity in Adult Women: Respiratory Exchange Ratio, Heart Rate Variation and Body Image

Factors Associated With Obesity in Adult Women: Respiratory Exchange Ratio, Heart Rate Variation and Body Image

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT04029532
Enrollment
121
Registered
2019-07-23
Start date
2019-04-01
Completion date
2020-01-14
Last updated
2020-08-12

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Obesity

Keywords

Respiratory exchange ratio, Body image, Heart rate variability

Brief summary

The prevalence of obesity all over the world has increased year by year, and how to effectively prevent and treat obesity has become an important health care issue. Many adjustable and nonadjustable causes of obesity have been proposed, such as unbalanced eating habits, lack of physical activity, psychological factors, and genes. The practice guidelines recommended lifestyle modification interventions which include diet control combined with regular exercise as the core treatment for obesity, but the effects on different ethnic groups are not ideal. In order to provide more choices for future weight loss intervention, it would be important to find out more risk factors for obesity. Previous studies have shown that lower sympathetic activity assessed by heart rate variability was related to obesity; obese men have higher respiratory exchange rates which might indicate they are more likely to use carbohydrates as a source of energy, and therefore, fat cannot be effectively consumed and led to an accumulation in the body. Furthermore, previous studies showed that Asians are less satisfied with their body image than other races, and women are more dissatisfied than men. Poor body image will lead to a series of effects, such as changes in eating habits, hormonal changes, depression, etc., eventually forming a vicious circle of obesity. However, most aforementioned Asians in these studies are immigrants living in overseas areas such as the Americas, and cannot fully represent the ethnic groups in Asia. Therefore, the purpose of this study are (1) to investigate the physiological and psychological factors influence obesity in adult women, including respiratory exchange rate, heart rate variability, and body image, and (2) to examine the correlations among these risk factors and different degree of obesity.

Detailed description

Methods: This is a cross-sectional design study. Subjects were recruited from Taipei city. Inclusion criteria are women aged between 20 and 50 years old and have willing to participate to this study. Subjects will be excluded as follows: (1) taking medications that affect weight or hormones; (2) fluctuation of weight exceeds 2 kg within 3 months before the enrolled in study; (3) any condition that causes the subject fail to complete the test paper, such as: cognitive problems; (4) diagnosed with mental illness; (5) pregnancy or menopause. The assessments include: obesity-related indicators (height, weight, waist and hip circumference, percentage of body fat), respiratory exchange ratio, heart rate variability, body image (multi-directional self-body relationship questionnaire (MBSRQ), figure rating scale (FRS)), physical activity (Seven-days Physical Activity Recall, 7-d PAR), eating behavior (Three-Factor Eating Questionnaire, revised 18-item, TFEQ-18), and depression (Mongomery-Asberg Depression Rating Scale, MADRS). Statistical analysis will be performed by using SPSS version 18 (SPSS Inc, Chicago: SPSS Inc.), and significant level would be set at 0.05. Analysis of variance (ANOVA) will be used to examine the differences of all measured variables among different degrees of obesity groups. In addition, we will use multiple linear regression analysis to examine whether overweight and obesity are significantly related to respiratory exchange rate, heart rate variability and body image.

Interventions

DEVICERespiratory exchange ratio

Ask participants to supine on bed, using a ventilator hood cover upon their head. Measure respiratory exchange ratio for 15 minutes.

DEVICEHeart rate variability

Ask participants to supine on bed for 10 minutes, connect electrodes on their right wrist. Measure heart rate variability for 5 minutes.

DEVICEBody composition

Ask participants to supine on bed for 10 minutes, connect electrodes on their right wrist and right foot. Measure body composition.

BEHAVIORALEating behavior

Fill in questionnaire (Three-Factor Eating Questionnaire, revised 18-item, TFEQ-18).

Fill in questionnaire (Seven-days Physical Activity Recall, 7-d PAR).

BEHAVIORALDepression

Fill in questionnaire (Mongomery-Asberg Depression Rating Scale, MADRS).

BEHAVIORALBody image

Fill in questionnaire (multi-directional self-body relationship questionnaire (MBSRQ), figure rating scale (FRS)).

Sponsors

National Taiwan University Hospital
Lead SponsorOTHER

Study design

Observational model
CASE_CONTROL
Time perspective
CROSS_SECTIONAL

Eligibility

Sex/Gender
FEMALE
Age
20 Years to 50 Years
Healthy volunteers
Yes

Inclusion criteria

* 20-50 years old, premenopausal

Exclusion criteria

* Taking medications that affect weight or hormones * Fluctuation of weight exceeds 2 kg within 3 months before the enrolled in study * Any condition that causes the subject fail to complete the test paper, such as: cognitive problems * Diagnosed with mental illness * Pregnancy or menopause

Design outcomes

Primary

MeasureTime frameDescription
Body image (evaluative component)After filling in multi-directional self-body relationship questionnaire (MBSRQ), lasting 5 minutes.Figure rating scale (FRS) is used. Nine figures of women (from lean to obese) is provided, participants are asked to choose which figure fits her present and ideal appearance the most. Scoring 1-9 points, greater value indicates poorer body image.
Respiratory exchange ratio (RER)After filling in all questionnaires, lasting 15 minutes.Ask participants to supine on bed, using a ventilator hood cover upon their head. Measure respiratory exchange ratio for 15 minutes. Device used: Vmax® Encore Metabolic Cart, Carefusion Corporation, Yorba Linda, California (CA). Normal range: 0.7-1.0, greater value indicates more carbohydrates oxidation, while smaller value indicates more fat oxidation.
Heart rate variability (HRV)After measuring respiratory exchange ratio, lasting 15 minutes.Ask participants to supine on bed for 10 minutes, connect electrodes on their right wrist. Measure heart rate variability for 5 minutes. Device used: SS1C, Enjoy Research Inc., Taiwan. High frequency (HF): greater value indicates active parasympathetic activity. Low frequency-high frequency ratio (LF/HF): greater value indicates active sympathetic activity.
Body imageAfter filling in basic data questionnaire, lasting 10 minutes.Fill in questionnaire (multi-directional self-body relationship questionnaire (MBSRQ)). There are 69 questions, each question scores 1-5 points. Sum up all points, greater value indicates better body image.

Secondary

MeasureTime frameDescription
Body fat percentageAfter measuring heart rate variability, lasting 5 minutes.Ask participants to supine on bed for 10 minutes, connect electrodes on their right wrist and right foot. Measure body fat percentage. Device used: Maltron BioScan 920-2. Greater value indicates higher body fat percentage.
Physical activityAfter filling in body image questionnaire, lasting 5 minutes.Fill in questionnaire (Seven-days Physical Activity Recall, 7-d PAR). Participants are asked to recall average time spent in a week on sleeping and activities of different intensities (Unit: metabolic equivalent of tasks (METs)). Sleeping, mild activity, moderate activity, vigorous activity, very vigorous activity are calculated as 1, 1.5, 4, 6, 10 METs respectively. Sum up all METs, divided by 7, we can obtain average daily energy expenditure. Greater value indicates more physical activity done.
Eating behaviorAfter filling in physical activity questionnaire, lasting 5 minutes.Fill in questionnaire (Three-Factor Eating Questionnaire, revised 18-item, TFEQ-18). This questionnaire includes 18 questions, scoring 1-4 points, except question 18 (1-8 points). Sum up all points, greater value indicates better eating behavior.
DepressionAfter filling in eating behavior questionnaire, lasting 5 minutes.Fill in questionnaire (Mongomery-Asberg Depression Rating Scale, MADRS). This questionnaire includes 10 questions, scoring 0-6 points. Sum up all points, greater value indicates more depressed.

Countries

Taiwan

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026