Trends in osteoporosis and low bone mass in older US adults, 2005-2006 through 2013-2014.

This study examined trends in osteoporosis and low bone mass in older US adults between 2005 and 2014 using bone mineral density (BMD) data from the National Health and Nutrition Examination Survey (NHANES). Osteoporosis and low bone mass appear to have increased at the femur neck but not at the lumbar spine during this period.

INTRODUCTION: Recent preliminary data from Medicare suggest that the decline in hip fracture incidence among older US adults may have plateaued in 2013-2014, but comparable data on BMD trends for this time period are currently lacking. This study examined trends in the prevalence of osteoporosis and low bone mass since 2005 using BMD data from NHANES. The present study also updated prevalence estimates to 2013-2014 and included estimates for non-Hispanic Asians.

METHODS: Femur neck and lumbar spine BMD by DXA were available for 7954 adults aged 50 years and older from four NHANES survey cycles between 2005-2006 and 2013-2014.

RESULTS: Significant trends (quadratic or linear) were observed for the femur neck (mean T-score and osteoporosis in both sexes; low bone mass in women) but not for the lumbar spine. The trend in femur neck status was somewhat U-shaped, with prevalences being most consistently significantly higher (by 1.1-6.6 percentage points) in 2013-2014 than 2007-2008. Adjusting for changes in body mass index, smoking, milk intake, and physician's diagnosis of osteoporosis between surveys did not change femur neck trends. In 2013-2014, the percent of older adults with osteoporosis was 6% at the femur neck, 8% at the lumbar spine, and 11% at either site.

CONCLUSIONS: There was some evidence of a decline in femur neck BMD between 2005-2006 and 2013-2014, but not in lumbar spine BMD. Changes in the risk factors that could be examined did not explain the femur neck BMD trends.