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

Completed
Conditions
Obesity
Interventions
Device: Respiratory exchange ratio
Device: Heart rate variability
Device: Body composition
Behavioral: Eating behavior
Behavioral: Physical activity recall
Behavioral: Depression
Behavioral: Body image
Registration Number
NCT04029532
Lead Sponsor
National Taiwan University Hospital
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.

Recruitment & Eligibility

Status
COMPLETED
Sex
Female
Target Recruitment
121
Inclusion Criteria
  • 20-50 years old, premenopausal
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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
Read More

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Non-overweight/obese & normal weightDepressionBody mass index (BMI) \< 24.0 kg/m\^2
Non-overweight/obese & normal weightBody compositionBody mass index (BMI) \< 24.0 kg/m\^2
Non-overweight/obese & normal weightPhysical activity recallBody mass index (BMI) \< 24.0 kg/m\^2
Non-overweight/obese & normal weightRespiratory exchange ratioBody mass index (BMI) \< 24.0 kg/m\^2
Non-overweight/obese & normal weightHeart rate variabilityBody mass index (BMI) \< 24.0 kg/m\^2
Non-overweight/obese & normal weightEating behaviorBody mass index (BMI) \< 24.0 kg/m\^2
Non-overweight/obese & normal weightBody imageBody mass index (BMI) \< 24.0 kg/m\^2
Overweight and obeseEating behaviorBody mass index (BMI) \>= 24.0 kg/m\^2
Overweight and obeseBody compositionBody mass index (BMI) \>= 24.0 kg/m\^2
Overweight and obeseHeart rate variabilityBody mass index (BMI) \>= 24.0 kg/m\^2
Overweight and obeseBody imageBody mass index (BMI) \>= 24.0 kg/m\^2
Overweight and obeseRespiratory exchange ratioBody mass index (BMI) \>= 24.0 kg/m\^2
Overweight and obesePhysical activity recallBody mass index (BMI) \>= 24.0 kg/m\^2
Overweight and obeseDepressionBody mass index (BMI) \>= 24.0 kg/m\^2
Primary Outcome Measures
NameTimeMethod
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.

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.

Secondary Outcome Measures
NameTimeMethod
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.

Trial Locations

Locations (1)

National Taiwan University, College of Medicine, Department of Physical Therapy

🇨🇳

Taipei, Zhongzheng, Taiwan

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