Osteoporosis fracture population burden
Osteop Int 2006 May 13; [Epub ahead of print], Pasco JA and others. The population burden of fractures originates in women with osteopenia, not osteoporosis. PMID: 16699736. Please read the abstract for details of this study. I want to just point out a few items that could be of interest to readers that I found in the full article. General summary. A general summary of this study is that it isn't only people with osteoporosis that are at risk for fractures. Indeed, in the Pasco and others study, the population with osteopenia contributed over half the fragility fractures during the study period. So men with osteopenia need to be aware that they are also at risk for fractures. Although the fracture risk is greater for individuals with osteoporosis, there are fewer of them in the population, thus explaining why the group with osteopenia actually contributed the greatest population burden due to fractures. The authors calculated the number of nationwide fractures during five years in Australia (where the study was done) would be 144,184 fractures from women with osteopenia compared to 76,710 arising from women with osteoporosis. Fracture risk and SD BMD decrease. The authors point out that a previous study found that for every standard deviation (SD) decrease in bone mineral density (BMD) there is a 1.5 to 3.0-fold increase in fracture risk. You would not be diagnosed as having osteoporosis if your BMD was, e.g., -2.3 SD from the young adult population. You could, however, have over a 6-fold increase in fracture risk. Five-year probability of study participants remaining fracture-free. The authors found that the probability for remaining fracture-free during the five year study for women with normal BMD was 92%, for women with osteopenia it was 80%, and for those with osteoporosis it was 66%. The importance of a previous fracture. A previous fracture for those with osteopenia was an important added risk factor for future fracture. Note that individuals with BMD in the osteopenia range and a history of a low-trauma fracture qualify for osteoporosis medication in the U.S. This is very important because Pasco and others found that a previous fracture more than doubled the risk for another fracture for individuals with osteopenia. Note that there was no increased risk for fracture for those with a previous fracture who had normal BMD. Other fracture risk factors. The study also found that increasing age and decreasing BMD were significant risk factors for fracture. Authors' suggestions. The authors state, “We have previously estimated the burden of fractures might be reduced by 16-30% in our community through maintenance of vitamin D levels near the summertime mean and vitamin D supplementation has been associated with a reduction in fracture risk in a community setting.” Editor's comments. It is doubtful that many men with osteopenia will actually know that or that they are at much greater risk of fracture because of their osteopenia. But those men with osteopenia and a history of fracture need to be aware that FDA-approved osteoporosis therapy is needed along with precautions to avoid a future fracture, such as arranging rooms to avoid tripping or falling. They also need to get a thorough osteoporosis diagnostic evaluation after a fracture whether their orthopedic surgeon recommends that or not. There is no mention of any study participants taking approved osteoporosis medications during the study. Certainly the women diagnosed with osteoporosis at the beginning of the study did qualify for therapy. I can only guess why they didn't receive it. But it seems obvious that the population fracture burden from those with osteopenia would have been even higher than it was if those with osteoporosis had been taking osteoporosis medications. That because their fracture rate would have been reduced by about one-half according to previous studies, while those with osteopenia (and not taking any approved medications) would have had the same fracture rate.