Vertebral fracture risk ‘predicted by four simple variables’
MedWire News: Vertebral fracture risk can be predicted using just four clinical variables with greater simplicity and accuracy than with the World Health Organization (WHO) fracture risk assessment tool (FRAX), concludes a team of Japanese researchers.
The FRAX was developed in 2008 to assign a 10-year absolute fracture risk based on clinical risk factors such as age, prior clinical fracture, current smoking, alcohol use, parental history of hip fracture, glucocorticoid use, rheumatoid arthritis, and bone mineral density (BMD).
To assess potential risk factors for predicting 4-year vertebral fracture risk, Saeko Fujiwara, from the Radiation Effects Research Foundation in Hiroshima, and colleagues conducted the Adult Health Study, in which 2613 men and women in Hiroshima with a mean age of 65 years were followed-up prospectively for 4 years.
Lateral and posterior-anterior spine radiographs were semiquantitatively analyzed to determine the prevalence and incidence of spine fractures, and participants were interviewed during biennial health examinations on incident nonvertebral fragility fractures in the hip, proximal humerus, and forearm/wrist.
In all, 215 participants experienced at least one incident vertebral fracture during the study period, while 75 participants had multiple incident vertebral fractures. Furthermore, 79 individuals experienced at least one nonvertebral fragility fracture, with 32 hip, 35 forearm/wrist, and 16 humerus fractures. A total of 281 individuals experienced either an incident vertebral and/or nonvertebral fracture.
The team reports in the journal Bone that a model including spine fracture status alongside WHO risk factors offered greater prognostic information on future fracture risk than a model that used the WHO risk factors alone, at a gradient of risk/standard deviation (GR/SD) of 2.73 versus 2.54.
The highest gradient of risk on univariate analysis was associated with age, BMD, prior clinical fracture, and spine fracture status, and a model including only these variables had a GR/SD of 2.67.
The researchers conclude: "Our study therefore demonstrates that the use of prevalent vertebral fracture status along with age, BMD, and prior clinical fracture has the capacity to predict future fracture risk at least as well as or better than the risk factors included in the WHO tool but with greater simplicity.
"Our findings provide the degree to which spine fracture burden offers future fracture risk prediction, show the importance of having such information as part of the routine evaluation for osteoporosis, and provide a practical approach for utilizing this information in Japan."
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By Liam Davenport