Can a bone density test tell you if you have osteoporosis? Does a high PSA level mean you have prostate cancer? What about hormone tests and menopause? We look at the tests and discuss their real diagnostic value.
PSA levels and prostate cancer
Prostate specific antigen (PSA) is a protein produced by prostate cells in men. The 'normal' value for total PSA is age-dependent — your body makes more PSA as you get older. But total PSA levels above 4.0 ng/mL may indicate prostate disease — infection, enlargement of the prostate gland or cancer. However a PSA test isn’t recommended as a stand-alone diagnostic test for prostate cancer.
Only one in four men with an elevated PSA level will have cancer. And some men who have prostate cancer have normal PSA levels. In order to diagnose prostate cancer, a PSA test needs to be used in conjunction with other tests (rectal examination and biopsy, for example).
Bone density and osteoporosis
Bone mineral density testing isn’t recommended as a general screening tool for osteoporosis. But if you have an increased risk of osteoporosis — you’re a woman aged over 45 and you fracture a bone after minimal trauma: falling from standing, for example — your doctor might refer you for testing to confirm a diagnosis.
The most accurate and reliable procedure for bone mineral density testing is dual energy x-ray absorptiometry (DEXA or DXA), a test in which a small amount of radiation is used to measure the density of the bones in the spine and hip, the most common areas for a fracture.
DEXA compares your bone mineral density to a reference population — most commonly healthy 30-year-old adults of the same sex — in order to give you a T-score. A score of 0 means your bone mineral density is equal to the norm for a healthy adult. A score between +1 and –1 is considered normal or healthy. A T-score of –2.5 or lower indicates osteoporosis.
Bone mineral density tests for all patients aged 70 years and over are covered by Medicare.
FSH levels and menopause
Follicle-stimulating hormone (FSH) stimulates the production of women’s eggs and is important in the regulation of menstruation.
The normal range of FSH depends on the stage of the menstrual cycle, and your age. During perimenopause — the transitional period before menopause which can last many years — FSH levels can fluctuate. After menopause they remain elevated.
However, hormone tests that measure FSH levels are of limited value for diagnosing menopause as results are so variable. Simply assessing symptoms can help establish a diagnosis.