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Body composition in Chinese subjects: relationship with age and disease
1Department of Medicine, The Chinese University of Hong Kong, Hong Kong, Hong Kong. jeanwoowong@cuhk.edu.hk
Archives of Gerontology and Geriatrics
|July 26, 2008
Summary
Body composition changes with aging in Chinese adults. Dual energy absorptiometry reveals BMI is less sensitive than body composition for detecting obesity or malnutrition, especially in older adults and those with chronic obstructive airways disease (COAD).
Area of Science:
- Gerontology
- Anthropometry
- Clinical Nutrition
Background:
- Accurate body composition data is crucial for assessing health in diverse populations.
- Existing reference values may not be applicable to Chinese adults, particularly the elderly.
- Chronic Obstructive Airways Disease (COAD) may impact body composition, necessitating specific reference data.
Purpose of the Study:
- Establish normal body composition reference values for adult Chinese, including the elderly.
- Investigate the influence of aging and COAD on body composition.
- Compare the efficacy of Body Mass Index (BMI) against body composition measurements for identifying obesity and malnutrition.
Main Methods:
- Dual-energy X-ray absorptiometry (DXA) was used to measure body composition.
- Study included 160 men and 407 women (aged 20-88 years), comprising volunteers and patients with COAD.
- Data analysis focused on age-related changes and comparisons between BMI and DXA-derived metrics.
Main Results:
- Significant differences in body composition were observed compared to Caucasian populations.
- Height and lean mass decreased linearly with age in both sexes.
- BMI demonstrated limited sensitivity (50-60%) in detecting obesity or undernutrition compared to body composition analysis.
Conclusions:
- Body composition changes significantly with aging in Chinese adults.
- DXA-based body composition measurements are superior to BMI for assessing obesity and undernutrition.
- Ethnic-specific reference values are essential for accurate health assessments.
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