Single BMD and Fracture Hx May Predict Risk of Fracture in Postmenopausal Women

A single assessment of bone mineral density (BMD) conducted by dual-energy X-ray absorptiometry (DXA), combined with a history of other risk factors, may have the ability to predict fracture risk for as long as 20 to 25 years, according to study results published in the American Society for Bone and Mineral Research.

Because most studies have looked at the relationship of BMD and future hip fracture during a 3- to 5-year span, Nicola Napoli, MD, from Campus Bio-Medico University in Rome, Italy, and colleagues examined the Study of Osteoporotic Fractures to analyze whether a single assessment of femoral neck BMD and fracture history was able to predict fracture risk over the course of 20 to 25 years. BMD and risk factors were assessed in 7959 white women aged 67 years or older. Hip fracture follow-ups continued for 25 years, and nonvertebral fracture follow-ups continued for 20 years.

The researchers found that cumulative incidence for hip fracture over the course of 25 years was 17.9%, and the incidence for nonvertebral fracture over the course of 20 years was 46.2%.

Women aged 80 years or older had a higher risk for hip fracture (22.6%) than women younger than 70 years (13.9%). Women aged 80 years and older also had a higher risk for nonvertebral fracture (50.0%) compared with women younger than 70 years (42.6%).

The range for long-term incidence of hip fracture was 29.6% in the lowest BMD quartile and 7.6% in the highest quartile. The long-term incidence range for nonvertebral fracture was 59.7% in the lowest quartile and 32.9% in the highest.

The researchers found that femoral neck BMD was a good predictor for long-term incidence of hip and nonvertebral fractures. Results showed that hip fracture history was more predictive of hip fracture risk (relative hazard, 1.6; 95% CI, 1.1-2.2) compared with nonvertebral fracture history (relative hazard, 1.6). In predicting nonvertebral fracture risk, history of hip fracture and nonvertebral fracture were equal (relative hazard, 1.6).

“We show that hip BMD is a remarkably persistent predictor of hip and nonvertebral fractures over 20 to 25 years and that self-reported history of any fracture also remains predictive over the very long-term,” the researchers said. “By following this cohort of older women for so long, we show directly that lifetime risk of hip fracture in community-dwelling women over age 75 years is extremely high,” the researchers wrote.

“These results strongly support the value of risk assessment and consideration of treatment even in the oldest, highest risk women,” they concluded.

Limitations

• This study does not address the value or optimal frequency of monitoring patients being treated for osteoporosis
• The participants in this study were only non-black women, so study data may not be generalizable to other populations
• Results from this study may underestimate true risks for fractures in untreated populations, because some participants were using bisphosphonates, raloxifene, or hormone therapy
• This study does not examine whether more recent fractures more strongly increase short-term fracture risk
• Although incident fractures were verified, fracture history was self-reported and unverified

Disclosures: DMB reports receiving grant support from Alexion and consulting fees from Amgen, Merck, Asahi-Kasei, and Radius. Dr Nicola Napoli reports receiving consulting fees from Amgen, MSD, UCB, and Eli Lilly. Dr Rachel Wagman is an employee of Amgen.

Reference

Black DM, Cauley JA, Wagman R, et al. The ability of a single BMD and fracture history assessment to predict fracture over 25 years in postmenopausal women: the study of osteoporotic fractures [published online July 18, 2017]. J Bone Miner Res. doi: 10.1002/jbmr.3194