Osteoporosis Diagnosis and Management

Initial Assessment and Risk Stratification

• A T-score of -3.0 indicates established osteoporosis, representing a high fracture risk requiring prompt treatment and closer monitoring, according to the European Journal of Nuclear Medicine and Molecular Imaging 1
• Women aged 65 and older should undergo bone densitometry regardless of additional risk factors, as recommended by the American College of Physicians and the US Preventive Services Task Force 2, 3, 4
• Men aged 50-69 should undergo bone densitometry if they have risk factors for osteoporosis, as recommended by the American College of Physicians 2
• Individuals with low body weight (<70 kg) should undergo bone densitometry, as recommended by the American College of Physicians 2
• Patients on medications that affect bone metabolism, such as glucocorticoids, aromatase inhibitors, GnRH agonists, and androgen deprivation therapy, should undergo bone densitometry, as recommended by the National Comprehensive Cancer Network 5

• The following classification system is used to diagnose bone density:

  T-score	Diagnosis
  > -1.0	Normal
  -1.0 to -2.4	Osteopenia
  ≤ -2.5	Osteoporosis

Monitoring and Follow-up

• Follow-up DEXA scans should be performed on the same machine as the baseline scan to ensure accurate comparisons, as recommended by the European Journal of Nuclear Medicine and Molecular Imaging 1
• Only changes that meet or exceed the least significant change (LSC) of 2.8-5.6% should be considered clinically meaningful, and changes should be evaluated using absolute BMD values in g/cm², not T-scores, according to the European Journal of Nuclear Medicine and Molecular Imaging 1
• The standard interval for bone densitometry is every 2 years for most patients, according to the American College of Physicians 8
• Follow-up DXA should be performed on the same machine as the baseline scan, typically every 2 years, but shorter intervals (1 year) may be considered for men on treatment or at risk for rapid bone loss, and for patients initiating therapy, patients at risk for substantial short-term decreases in mineralization, and patients on glucocorticoid therapy, with absolute BMD values in g/cm² compared on follow-up scans, not T-scores, according to the American College of Radiology and the European Journal of Nuclear Medicine and Molecular Imaging 6, 7, 1, 9
• Patients on glucocorticoid therapy, with conditions associated with rapid bone loss, or with cholestatic liver disease and multiple risk factors may warrant shorter follow-up intervals, such as annual scans, as suggested by the Journal of Hepatology 10

Interpretation of Scan Results and Treatment

• Bone density measurement at the femoral neck using DXA is the best predictor of hip fracture, as reported by the American College of Physicians 8
• Previous fragility fracture, regardless of bone mineral density, is an indication for treatment, according to the American Family Physician, and vertebral fractures detected on DXA vertebral fracture assessment (VFA) are an indication for treatment, even if BMD is not in osteoporotic range 11, 6
• The FRAX tool is used to calculate the 10-year probability of fracture, integrating clinical risk factors with bone mineral density, and treatment is recommended when the 10-year probability of hip fracture ≥3% or a 10-year probability of major osteoporotic fracture ≥20% 6, 7, 4, 1, 12, 11
• Medications associated with bone loss, including glucocorticoids, aromatase inhibitors, GnRH agonists, anticonvulsants, proton pump inhibitors, and certain antidepressants, increase the risk of osteoporosis and may require treatment consideration 4, 5
• Laboratory evaluation for secondary causes of osteoporosis should include basic tests such as ESR, calcium, albumin, creatinine, and TSH, with additional tests like vitamin D and protein electrophoresis when indicated, as recommended by EULAR/EFORT guidelines 13
• Patients with fall-related fractures should undergo bone health evaluation, as recommended by the American Academy of Orthopaedic Surgeons 14
• High-risk patients, such as those with a history of frequent falls, should be evaluated for fracture risk, including DXA scanning, according to EULAR/EFORT guidelines 13