BMD blood test: what it checks

Bone mineral density is assessed with a scan, while blood testing looks for clues that may affect bones or influence treatment. Depending on your symptoms and history, a clinician may assess blood cell counts, kidney function, calcium-related measures, vitamin levels, thyroid activity or inflammation. The results are interpreted together with age, medicines, fractures, menstrual or hormonal history and other health conditions. An abnormal result does not by itself confirm osteoporosis.

Ask whether you need to fast, take your usual medicines, or avoid supplements before the sample. Tell the clinician about steroid treatment, anticonvulsants, kidney problems, digestive symptoms and previous fractures. A small blood sample is usually taken from a vein. Results may lead to repeat testing, a bone-density scan, or treatment of an underlying issue such as anaemia, coeliac disease or chronic kidney disease.

Contact a clinician promptly after a fall with severe pain, inability to bear weight, a suspected fracture, sudden muscle spasms or marked weakness. Seek urgent help for chest pain, breathing difficulty, fainting or heavy bleeding. These symptoms are not explained by a routine BMD blood test and need their own assessment.

Ask which markers are being checked, whether fasting is required, when results will be ready, and whether a bone-density scan is also appropriate. Clarify what an abnormal result could mean for your medicines, nutrition and follow-up.