Approved research

Biochemical evaluation of secondary osteoporosis: A UK Biobank study

Lay summary

Osteoporosis is a common disorder characterised by reduced bone strength and an increased susceptibility to broken bones. Osteoporosis may occur secondary to other potentially treatable medical conditions, and the study aim is to determine the usefulness of blood tests for diagnosing these secondary causes of osteoporosis. This study will be undertaken by comparing whether subjects with osteoporosis, as diagnosed by the presence of low bone mineral density (BMD) values and/or fractures, have more frequent blood test abnormalities compared to subjects without osteoporosis. These findings will establish which blood tests are of help for the clinical assessment of osteoporosis. Osteoporosis represents a global health burden, and in the UK causes more than 300,000 fractures every year, with annual hospital costs of greater than £1.9 billion (National Osteoporosis Society). The goal of this study is to identify laboratory tests that can be used to diagnose osteoporosis caused by potentially treatable medical conditions such as hypogonadism, vitamin D deficiency and primary hyperparathyroidism. This objective is therefore in keeping with the aims of the UK Biobank, which are to improve ?the prevention, diagnosis and treatment of a wide range of serious and life-threatening illnesses ? including?osteoporosis?? (UK Biobank website). We propose to evaluate the frequency of abnormal osteoporosis related biomarkers, which are currently included in the UK Biobank panel (e.g. serum calcium, alkaline phosphatase, creatinine, vitamin D, and testosterone) to assess whether alterations in these biomarkers occur more commonly in the following participant groups: 1. Participants with low impact fractures compared to participants without low impact fractures. 2. Participants from the DXA-assessment cohort who have osteoporotic bone mineral density (BMD) values compared to participants with osteopaenic (i.e. mildy reduced) or normal BMD values. We propose to evaluate the following participants: 1. Participants who provided information on experiencing a fracture after a simple fall (>49,000 participants; data-field 3005) 2. DXA-assessment cohort participants who have had spine, hip and whole-body BMD measured (~10,000 participants; category 125) For our primary analysis, 'osteoporosis' is defined as a femoral neck BMD T-score of =-2.5, based on NHANES III gender-specific data. We will define 'severe osteoporosis' as low BMD and the presence of a low trauma fracture since age 40. These definitions are in line with the WHO osteoporosis working group.