Men's Osteoporosis Support GroupBone mineral density and fractures Osteoporos Int. 2009 Apr 22. [Epub ahead of print]. Bone fragility in male glucocorticoid-induced osteoporosis is not defined by bone mineral density. Hayashi K and others. PMID: 19387764. This Japanese study involved 87 men who were taking >/=5 mg of prednisolone, a glucocorticoid, for more than six months who were compared to age- and body mass index-matched controls to test how effective bone mineral density (BMD) measurement was at predicting vertebral fracture (VF) risk. The results showed that use of glucocorticoids (GCs) was an independent risk factor for VFs, odds ratio 10.93, P < 0.001. [Comment: This means men on GC therapy are about 11 times more likely to fracture than the age- and BMI-matched controls not taking GCs]. Additionally the authors found, "Multiple regression analysis adjusted for age and BMI showed that spinal BMD in the GC group was not associated with prevalent VFs, even after adding current and past maximum GC doses as independent variables." The authors concluded: "These results show that lumbar BMD values are not associated with prevalent VFs in GC-treated male patients, suggesting that bone fragility in male GC users is affected by bone quality rather than by BMD." Editor's comments. There are many articles on this site regarding the risk of osteoporosis in individuals who take GCs--and it is highly elevated. Here is an Update with the guidelines for treating and/or preventing glucocorticoid-induced osteoporosis. The important finding in this article is that BMD is not a perfect indicator of fracture risk, especially in people taking GCs. I have discussed the bone quality issue in another Update in 2008. In summary there can be both qualitative and quantitative changes in the bone when individuals have osteoporosis. The quantitative changes are measured by BMD testing with dual-energy X-ray absorptiometry, DXA. But the only way to measure bone quality is with a biopsy and microscopic evaluation of the results. This study shows that bone quality can be a causal agent for fractures, even when BMD appears normal with bone density tests. Bottom line for men taking GCs: After six months of GC therapy of greater than 5-mg/day you are 11 times more likely to suffer a VF than than similar men who aren't on GC therapy. This even though your DXA is still normal. The only way to prevent these fractures is to start preventive therapy with one of the approved osteoporosis medications. So be sure to discuss this with your physician if you are starting high-dose GC therapy.
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