Aim of monitoring is to increase adherence to therapy and to verify response to therapy

Bone Mineral Density (BMD) Measurement

• Recommended every 1-3 years after initiation of therapy until findings are stable and every 2 years thereafter 
• Central dual energy X-ray absorptiometry (DXA) of the spine or hip is the gold standard for serial BMD assessment
  
  • Should be done every 2 years
  • If spine, hip or both cannot be assessed, 33% radius site can be used
• Patient follow-up ideally should be done within the same facility using the same machine 
• Age-, disease- and treatment-related BMD changes can be monitored using quantitative computed tomography (QCT) measurement of trabecular BMD 

Bone Turnover Markers

• Bone resorption markers may be measured before starting therapy and 3 or 6 months after starting treatment
• Bone formation markers may be measured before starting therapy and 6 months later
• High levels of bone resorption markers are associated with an increased risk of osteoporotic fractures
  
  • Resorption markers may be used for assessing fracture risk in selected patients when BMD and clinical risk factors are not sufficient to make treatment decisions

Vertebral Imaging

• Repeat vertebral imaging is indicated for patients with the following:
  
  • Documented height loss
  • Presence of vertebral pain
  • Changes in posture
  • Chest X-ray abnormalities
  • Due for reevaluation of treatment with possible withdrawal of therapy
  • Presence of vertebral fracture during off-treatment interval

• Postmenopausal women who have been taking oral bisphosphonates for >5 years or IV bisphosphonates for >3 years should be reassessed for presence of fractures prior to initiation and during therapy
  • Bisphosphonate therapy can be continued beyond 3-5 years in patients ≥75 years old, on high-dose oral glucocorticoid treatment, with prior history of hip or vertebral fracture, or who sustained a low-trauma fracture during therapy
• If fractures occurred, treatment with bisphosphonates may be continued or may consider the use of other agents
• If fracture-free, assess BMD T-score or fracture risk
  • If with hip BMD T-score of <-2.5 or with high fracture risk, consider continuing bisphosphonate therapy or may change into other alternative agents
  • If with normal bone mass and still no fractures, may consider withholding treatment and advise patient to follow up for fracture risk assessment every 1.5-3 years

Specialist Referral

• Consider a referral to a specialist when: 
  • Multiple fragility fractures are experienced
  • A non-major trauma fracture is sustained by a patient with normal BMD 
  • With a very low BMD (T-score < -3)
  • Continued bone loss or recurrent fractures happen in a patient on therapy but has no clear causes of bone loss that are treatable
  • Osteoporosis has uncommon features, is severe, or rare secondary conditions are present, eg hyperparathyroidism, increased prolactin
  • A condition is present that makes management difficult, eg chronic kidney disease, malabsorption