Grant: Operating Grant

One in 4 women and at least 1 in 8 men over age 50 has osteoporosis, affecting over two million Canadians. Osteoporotic fractures are caused by poor bone strength, determined by bone density, structure and ability to resist force. Together, these properties constitute bone quality. Osteoporosis is currently diagnosed with two-dimensional bone density scans that predict less than a third of those who fracture. High and low resolution CT scanners each give three-dimensional information on bone quality. However, it is unknown which bone measures are best for diagnosing osteoporosis and which CT scanner provides the most useful information. The goal of this study is to compare high and low resolution CT scanners to identify bone quality measures that best estimate someone's risk for fracture(s). A 5-year multiple centre study will be conducted to measure bone quality using the two technologies at the beginning of the study in over 1000 men and women who are part of the Canadian Multicentre Osteoporosis Study. Detailed fracture information will be collected from participants over the 5 years of follow-up and from the past fifteen years. Bone quality measures from high and low resolution CT scanners will be compared in terms of their ability to predict fractures and to detect someone who had a fracture. The study will also examine how bone quality measures can provide added value to the current standard of care: the use of bone density plus basic risk factors for osteoporosis. To strengthen the results of the study, the analyses will be repeated 200 times using a computer model to see if the same results arise. The information from this study will guide improved diagnosis of osteoporosis by selecting the most informing bone quality measures and seeing how they can complement bone density scans. It will also generate a large nationwide data set available to Canadian researchers who can then examine how exercise, nutrition, drugs and other diseases affect bone quality.