The Assessment of Bone Health in a Clinical Setting

Patients are referred for assessment of their bone health routinely have a bone density (BD) scan (DXA) and many also have a bone marker (BM) measurement, either NTx ( breakdown product of bone) or PINP ( formation product of bone). Patients diagnosed with osteoporosis are usually treated with a bisphosphonate drug which can halt or at least decrease the rate of bone loss.

BMs are measured pre- and post -treatment to assess adherence and effectiveness of treatment. BD measured by DXA is also used for this but in clinical practice is not recommended at intervals of less than 2 years. BMs show a much earlier clinical meaningful change - typically 2-6 months, vs BD -typically 2 years, thereby aiding swift knowledge of response or lack of response to treatment.

Although DXA remains the gold standard for initial assessment of bone health by measuring BD, BMs have an increasing role to play in patient follow up.

We propose to interrogate available data to explore whether utilizing BMs can provide monitoring information up to 5 years post-treatment thereby increasing the follow up time of the next DXA scan. This would ensure patients are not being subjected to scans using x-rays unduly and that a DXA scan is only performed when clinically needed. Additionally we want to investigate if BM levels pre-treatment reflect the response to treatment of the marker and BD, prediction of BM levels from age, fracture history, treatment, and does site of fracture affect BM and BD.

Previous work by other investigators has covered some of this ground but has not come up with definitive answers.

The study is expected to take 5 years and will not involve additional investigations compared to standard care.