title: Body composition: gender-specific risk factor of reduced quantitative ultrasound measures in older people.
abstract: BACKGROUND
  Body composition has been reported as a significant determinant of bone mineral density. However, data regarding the relationship between the body composition and quantitative ultrasound (QUS) are scarce.
  
  
  METHODS
  This cross-sectional study examined risk factors of reduced QUS measures in older men and women. A total of 699 subjects aged 60 years old and over-458 women and 241 men-who lived in rural communities of Thailand were randomly recruited.
  
  
  RESULTS
  By using broadband ultrasound attenuation at the cutoff point of mean -1.0 SD based on young Thai people, the independent factors associated with reduced QUS measures in men were: poor activity of daily living, older age, and low fat mass. As for older women, the independent factors were the number of years since menopause, lack of regular exercise, lower height, and low fat mass. When using the stiffness index at the cutoff point of mean -1.6 SD based on young Thai people, the independent factors associated with reduced QUS measures in men were older age and low fat mass. Meanwhile, the number of years since menopause and low lean body mass were independent risk factors in women.
  
  
  CONCLUSIONS
  Poor activity of daily living in men or lack of regular exercise in women was found to be a modifiable risk factor of reduced QUS measures. Years since menopause and low lean body mass were significant factors determining reduced QUS measures in women. Fat mass was an independent factor associated with reduced QUS measures both in men and women.
authors: Department of Preventive & Social Medicine, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, 10700, Thailand. sipus@mahidol.ac.th
authors: P
authors: P
authors: Assantachai
authors: S
authors: S
authors: Sriussadaporn
authors: V
authors: V
authors: Thamlikitkul
authors: K
authors: K
authors: Sitthichai