Predicting various fragility fractures in women by forearm bone densitometry: A follow-up study

Summary

This is a follow-up of a previous study on the predictive power of bone mineral measurements; two more observation years have been added. A group of women (n=1076) had their forearm bone mineral content (BMC) measured from 1970–1976. All fractures that occurred in 1975–1987 (13 years) were recorded. Four hundred sixty-nine fragility fractures occurred during the collection period. Again, it was found that BMC at the distal end of the forearm is a good predictor of future fracture before the age of 70. The measurement at the proximal site (forearm shafts), however, in contrast to our previous study, has a capacity of predicting fracture also in the age group 70–80. BMC measurements were good predictors of vertebral crush fractures and trochanteric hip fracture but lesser predictors of fractures of the distal end of the forearm. In age groups 40–70, BMC was a stronger predictor of fracture than age, and the risk associated with a 1 SD decrease of BMC 6 was 3.2 for a hip fracture as compared with those without any fragility fracture, even when adjusted for age. In addition to BMC, low body weight was a fracture predictor. Body weight 5 kg below age-adjusted mean increased the risk of a trochanteric hip fracture by 30%. The data are used in hypothetical calculations of the effects of screening.