The expanded National Bone Health Alliance (NBHA) definition of osteoporosis may better identify those at elevated fracture risk and ultimately help identify strategies to reduce the burden of fractures in older adults, according to findings from a Dec. 13 study published in Osteoporosis International. The study evaluated osteoporosis prevalence using the expanded diagnostic criteria. The study authors, N.C. Wright et al., analyzed 2005–2008 data from the National Health and Nutrition Examination Survey (NHANES).
“We found that 16% of men and 29.9% of women 50+ have osteoporosis based on the NBHA diagnostic criteria. Although the expanded definition increases the prevalence compared to BMD alone-based definitions, it may better identify those at elevated fracture risk in order to reduce the burden of fractures in older adults,” the authors wrote.
The study was conducted in response to a published position statement from a 2014 National Bone Health Alliance working group under E. F. Siris, MD, University of Alabama. It argued for such expanded criteria for osteoporosis diagnoses in postmenopausal women and men age 50 and older. At the time, the only means for establishing an osteoporosis diagnosis was T-scores of -2.5 or lower from bone mineral density (BMD) testing at the spine or hip. The premise of the position paper, Dr. Siris said in an email with Rheumatology Network, was that because osteoporosis signifies reduced bone strength that predisposes older people to bone fracture, other factors predicting for fracture besides low BMD testing should be considered diagnostic.
Included among those other factors are 1) prior hip fracture, 2) in the setting of osteopenia, vertebral, pelvic, proximal humerus or in some cases distal forearm fractures, and 3) FRAX scores meeting or exceeding levels indicating need for treatment in the US by the National Osteoporosis Foundation Clinician’s Guide (10 year probability of hip fracture of 3% or greater, or for major osteoporotic fracture 20% or greater).
Wright, et al. observed further that certain low trauma fractures, especially those of the hip and spine, are included in many osteoporosis treatment guidelines, both national and international, out of recognition that these types of fractures are indicative of osteoporosis in the absence of a BMD T-score.
When osteoporosis diagnosis is based on BMD measurements at the femur neck and/or lumbar spine with a T-score of ≤−2.5, the estimated osteoporosis incidence among adults 50 years and older in the US is 10.3%.
In the included study sample of 3,587 adults (1,948 men, 1,639 postmenopausal women) with complete information, about a third of the sample was 50–59 years (30.6%) and 34.9% was between 60 and 69 years of age.
The osteoporosis prevalence rates overall for individuals meeting any of the three NBHA criteria were 16.0% for men and 29.9% for women 50 years and older. The prevalence of osteoporosis with the NBHA diagnostic criteria increased with age, as expected. In men, the estimated prevalence increased from 5.5 to 46.3% between the 50–59 and the 80+ age groups. In women, the prevalence increased from 10.9% in the 50–59 age group to 77.1% in the 80+ age group. The trend was statistically significant for both sexes (p=0.001). The finding, according to Wright et al, underscores “the importance of advancing age as one of the primary risk factors for osteoporosis and fracture.”
The authors concluded, “If there is to be an ongoing public health effort to reduce the burden of fractures in older women and men, the identification of those at elevated fracture risk and the development of management strategies to lower risk where it is found remains an important public health goal.”
“The data suggest that if we are to lower the serious burden of fractures in older Americans (~2 million per year)…all those at risk need to be identified,” Dr. Siris said.
N. C. Wright, K. G. Saag, et al. “The impact of the new National Bone Health Alliance (NBHA) diagnostic criteria on the prevalence of osteoporosis in the USA.” Osteoporosis International. First online Dec. 13, 2016. DOI 10.1007/s00198-016-3865-3.
E. S. Siris , R. Adler et al. “The clinical diagnosis of osteoporosis: a position statement from the National Bone Health Alliance Working Group.” Osteoporosis International. Published online: Feb. 28, 2014. DOI 10.1007/s00198-014-2655-z.