Co-ordinated research project: comparative international studies of osteoporosis using isotope techniques

Poor bone health is a major public health problem of worldwide concern. No country is immune. One of the main concerns - osteoporosis - is a bone disease that usually affects older people (primarily post-menopausal women), leading to hip fractures, vertebral compression fractures, and other related problems.In 1994 the IAEA (henceforth the 'Agency') started a 5-year Co-ordinated Research Programme (CRP) which addresses one particular measure of bone health - bone mineral density (BMD). The main concept underpinning this CRP is that good bone health in later years is primarily determined by the attainment of a sufficiently high BMD during early adulthood. The 'core' objective of the Agency's CRP is to investigate how BMD varies with the age, sex, ethnicity and geographical origin of the subjects over the age range from 15 to 50 years. This is being done in the hopeful expectation that, by looking at a large number of population groups with different lifestyle, nutritional and other parameters, it might be possible to obtain some new insights into which factors are important for attaining a high value of BMD during early adulthood, and for being able to maintain it at a sufficiently high level into old age. The Second Research Co-ordination Meeting (RCM) for participants in the CRP - which is the subject of the present report - was held at the University of California San Diego (UCSD), USA. An overview of the data on BMD reported by the participants during the meeting. It is concluded that the CRP participants have gathered an impressive amount of data over the last 2 years. Given the fact that some age groups contain relatively small numbers of subjects, the statistical uncertainties are still relatively large. Nevertheless, there do appear to be quite marked differences in BMD across the centres, approaching approximately 10%. If confirmed, this could represent a major difference in fracture risk for the future, if all other factors (bone quality, weight, fall predisposition) were equal. Comparison of the data from the different centres participating in the CRP following standardisation by the ESP and the collection of at least 25 subjects in each 5-year category of age and sex will therefore be of great interest. More information on the progress achieved by individual participants, and on their future plans for implementation of the CRP, is presented in their respective country reports