Arch Osteoporos (2014) 9:175 DOI 10.1007/s11657-014-0175-2
ORIGINAL ARTICLE
Body mass index is positively associated with bone mineral density in US older adults Jennifer T. Lloyd & Dawn E. Alley & William G. Hawkes & Marc C. Hochberg & Shari R. Waldstein & Denise L. Orwig
Received: 26 June 2013 / Accepted: 19 August 2013 # International Osteoporosis Foundation and National Osteoporosis Foundation 2014
Abstract Summary Literature has been conflicting as to whether obesity is protective against osteoporosis. Understanding the relationship is particularly important in light of the increasing prevalence of obesity among older adults. Study results confirm a protective association between obesity and osteoporosis in a recent, nationally representative sample of US older adults. Purpose Currently, the majority of US older adults are either overweight or obese. Evidence regarding the relationship between body composition measures and bone mass is conflicting, possibly because different measures of obesity reflect multiple mechanisms. Additionally, there are important age, gender, and racial differences in a risk of osteoporosis and fat mass composition. The objective of this study was to examine the association between body mass index (BMI) and bone mineral density (BMD) in a recent, nationally representative sample of US older adults as well as to see if this relationship differs by age, sex, and race. Methods Data for this study were obtained from the National Health and Nutrition Examination Survey (2005–2008) for adults ages 50 and older (n=3,296). Linear regression models were used to predict BMD of the femoral neck (measured by dual-energy X-ray absorptiometry (DXA)) as a function of BMI (measured height and weight) and a range of study covariates.
D. E. Alley : W. G. Hawkes : M. C. Hochberg : D. L. Orwig Department of Epidemiology and Public Health, School of Medicine, University of Maryland, Baltimore, USA J. T. Lloyd (*) : D. E. Alley : W. G. Hawkes : S. R. Waldstein : D. L. Orwig Doctoral Program in Gerontology, University of Maryland, Baltimore and Baltimore County, USA e-mail: [email protected] S. R. Waldstein Department of Psychology, University of Maryland, Baltimore, USA
Results Every unit increase in BMI was associated with an increase of 0.0082 g/cm2 in BMD (p = 30.00)] was used in bivariate analyses to test the relationship between covariates and BMI groups. The sample excluded underweight individuals (BMI0.79 g/cm2 for men and >0.74 g/cm2 for women, corresponding to a T-score of −1 or higher); osteopenia (BMD, > = 0.59 and < = 0.79 g/cm2 for men and > = 0.56 and < = 0.74 g/cm2 for women, corresponding to a T-score between −1 and −2.5); osteoporosis (BMD,
ORIGINAL ARTICLE
Body mass index is positively associated with bone mineral density in US older adults Jennifer T. Lloyd & Dawn E. Alley & William G. Hawkes & Marc C. Hochberg & Shari R. Waldstein & Denise L. Orwig
Received: 26 June 2013 / Accepted: 19 August 2013 # International Osteoporosis Foundation and National Osteoporosis Foundation 2014
Abstract Summary Literature has been conflicting as to whether obesity is protective against osteoporosis. Understanding the relationship is particularly important in light of the increasing prevalence of obesity among older adults. Study results confirm a protective association between obesity and osteoporosis in a recent, nationally representative sample of US older adults. Purpose Currently, the majority of US older adults are either overweight or obese. Evidence regarding the relationship between body composition measures and bone mass is conflicting, possibly because different measures of obesity reflect multiple mechanisms. Additionally, there are important age, gender, and racial differences in a risk of osteoporosis and fat mass composition. The objective of this study was to examine the association between body mass index (BMI) and bone mineral density (BMD) in a recent, nationally representative sample of US older adults as well as to see if this relationship differs by age, sex, and race. Methods Data for this study were obtained from the National Health and Nutrition Examination Survey (2005–2008) for adults ages 50 and older (n=3,296). Linear regression models were used to predict BMD of the femoral neck (measured by dual-energy X-ray absorptiometry (DXA)) as a function of BMI (measured height and weight) and a range of study covariates.
D. E. Alley : W. G. Hawkes : M. C. Hochberg : D. L. Orwig Department of Epidemiology and Public Health, School of Medicine, University of Maryland, Baltimore, USA J. T. Lloyd (*) : D. E. Alley : W. G. Hawkes : S. R. Waldstein : D. L. Orwig Doctoral Program in Gerontology, University of Maryland, Baltimore and Baltimore County, USA e-mail: [email protected] S. R. Waldstein Department of Psychology, University of Maryland, Baltimore, USA
Results Every unit increase in BMI was associated with an increase of 0.0082 g/cm2 in BMD (p = 30.00)] was used in bivariate analyses to test the relationship between covariates and BMI groups. The sample excluded underweight individuals (BMI0.79 g/cm2 for men and >0.74 g/cm2 for women, corresponding to a T-score of −1 or higher); osteopenia (BMD, > = 0.59 and < = 0.79 g/cm2 for men and > = 0.56 and < = 0.74 g/cm2 for women, corresponding to a T-score between −1 and −2.5); osteoporosis (BMD,
