Prevalence of Normal-Weight Obesity in Community-Dwelling Chinese Older Adults: Results from the Beijing Longitudinal Study of Aging

OBJECTIVE: Normal-weight obesity (NWO) is characterized by high body fat percentage (BFP) in individuals with normal body mass index (BMI). This condition may increase the risk of serious health problems, such as cardiovascular diseases, diabetes, insulin resistance, hypertension, and metabolic syndrome. However, the prevalence of NWO in older adults in Beijing remains unclear. This study aimed to investigate the prevalence of overweight and obesity among older adults in Beijing, using three obesity assessment indicators: BMI, waist circumference, and BFP. DESIGN: Cross-sectional study. SETTING AND PARTICIPANTS: Data were obtained from the 2012 Beijing Longitudinal Study of Aging, which used a stratified, sectional, random, and cluster sampling method. METHODS: Questionnaires, physical examinations, and laboratory tests were completed. Obesity was divided into four categories based on combinations of BMI and BFP: non-obese, muscle-type obesity, NWO and fatty obesity. RESULTS: A total of 2393 community-dwelling older adults with an average age of 72.98±8.09 years old were recruited. Of them, 1051 were male (43.92%) and 1245 were living in rural areas (52.03%). The prevalence of overweight and obesity among older people in Beijing was 35.5% and 16.1%, respectively. When the sample was divided according to obesity classification, the proportion of muscular obesity, NWO and adipose obesity was 14.7%, 10.7%, and 41.8%, respectively. The prevalence of central obesity was 62.3%. The prevalence of obesity decreased with age, but it was higher in females than in males as well as among individuals living in urban areas than in individuals living in rural areas. CONCLUSION: The prevalence of NWO was 10.7% among older adults in Beijing and increased with age. Older adults who are female or living in urban areas should be instructed to take measures aimed at reducing body fat and increasing muscle strength.