A recent major osteoporotic fracture (MOF) in women aged <65 years is associated with an increased risk for another MOF for up to 10 years, with the first 2 years following the initial fracture presenting the highest risk. The results were published in the Journal of Bone and Mineral Research.
Investigators sought to determine the effect of previous fracture, according to recent (<2 years) and remote (≥2 years) incidence, and fracture site on incident fracture risk predictions using the Fracture Risk Assessment Tool (FRAX®) which can estimate the 10-year fracture probability for MOF.
Eligible participants were women aged ≥40 years with baseline dual-energy x-ray absorptiometry (DXA) scans from January 1, 1996, to March 31, 2016. Participants had ≥5 years of coverage before and ≥2 years of observation, with a maximum of 10 years. Data were obtained from the Manitoba Bone Mineral Density (BMD) Program registry.
The study population included 33,465 women aged less than 65 years, (mean age, 55.3 years) and 33,806 women aged ≥65 (mean age, 73.4 years). The prevalence of MOF in the preceding 2 years was significantly lower in the younger group of women compared with the older group (5.7% vs 7.0%, respectively) and was also lower for MOF occurring >2 years earlier (6.3% vs 12.2%, respectively).
Regarding fractures in the initial 2 years of observation, when MOF risk was stratified by fracture site and time since fracture, the only statistically significant effect of recency in women aged <65 years was for vertebral fracture (P < .001), with an odds ratio (OR) of 5.94 (95% CI, 3.72-9.49) when it occurred in the previous 2 years, vs 1.24 (95% CI, 0.64-2.44) when it occurred >2 years earlier. For women aged ≥65 years, the only significant time dependency was for previous hip fracture (P = .033), with OR 1.91 (95% CI, 1.32-2.76) when this occurred in the prior 2 years vs 1.04 (95% CI, 0.66-1.61) when this occurred >2 years previously.
Regarding fractures occurring within 10 years, 5057 incident MOF (1633 and 3424 for women aged 40-64 years and ≥65 years, respectively) and 1576 incident hip fractures occurred (217 and 1359 for women aged 40-64 years and ≥65 years, respectively). In women aged <65 years, recent MOF was associated with an increased risk for subsequent MOF that exceeded the risk for women who had no previous fracture or a fracture that occurred >2 years previously. This increased risk was sustained for up to 10 years.
A comparison of the observed 10-year fracture probability with FRAX-predicted probability showed good calibration, according to the study authors. An effect of fracture within the previous 2 years was found after a vertebral fracture in women aged <65 years (calibration ratio 1.61; 95% CI, 1.18-2.04) and after a humerus fracture (calibration ratio 1.48; 95% CI, 1.05-1.92), which investigators said was an indication that FRAX underestimated the true fracture probability. However, FRAX did not significantly underestimate MOF probability in any analysis in women aged ≥65 years.
Study limitations acknowledged by the investigators included the possibility of early same-site fractures (within 3-6 months) being excluded from the study, and lifestyle factors could not be assessed. Additionally, the Manitoba BMD Registry population is almost exclusively (>97%) White and the analysis was in women only, therefore the results may not apply to other ethnicities or men.
The investigators concluded the risk of MOF and hip re-fracture remained elevated over 10 years. “Our findings present further evidence for the excess fracture risk associated with recent fracture,” stated the researchers, noting this effect was not consistent across fracture sites.
“A first fracture should continue to be regarded as a major risk factor for a second fracture and calls for a thorough clinical evaluation and appropriate initiation of nonpharmacologic interventions, medications, and falls prevention to reduce that risk,” they said.
Disclosure: Some of the study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Leslie WD, Morin SN, Lix LM, et al. The effect of fracture recency on observed 10-year fracture probability: a registry-based cohort study. J Bone Miner Res. Published online February 11, 2022. doi:10.1002/jbmr.4526