A 65-year-old woman comes to the office to discuss the results of bone density testing. She is worried because her 85-year-old mother recently died while recovering from a hip fracture. The patient does not use tobacco or alcohol and gets regular exercise. Her last menstrual period was 13 years ago, and she is not taking any form of hormone replacement therapy. Vital signs and physical examination are within normal limits. BMI is 19 kg/m2. DXA scan reveals a T-score of −1.8 at the lumbar spine and −1.7 at the hip, consistent with osteopenia. In addition to appropriate calcium and vitamin D supplementation, which of the following is the most appropriate next step in management of this patient?
Postmenopausal osteoporosis | |
Diagnosis |
|
Initial evaluation |
|
Lifestyle therapy |
|
Pharmacologic therapy |
|
*Calculated 10-year risk of hip fracture ≥3% or combined major fracture ≥20%. | |
On DXA testing, the T-score indicates how a patient's bone density compares to an average young adult at peak bone density. A T-score ≥−1.0 is considered normal, between −1.0 and −2.5 is osteopenia, and ≤−2.5 is osteoporosis. This postmenopausal woman has osteopenia and other significant risk factors for fracture, including low BMI and family history of parental hip fracture.
All patients with low bone density (osteopenia or osteoporosis) should get regular weight-bearing exercise, avoid smoking and excessive alcohol intake, and maintain adequate intake of calcium and vitamin D (using supplements as needed). Patients with osteoporosis (by DXA criteria or confirmed osteoporotic fracture) also warrant antiresorptive therapy; bisphosphonates (eg, alendronate) are first-line treatment for most patients.
In addition, patients with osteopenia who are at increased risk of fracture may benefit from bisphosphonate therapy. The 10-year fracture risk can be calculated using the Fracture Risk Assessment Tool (FRAX), which takes into account bone density, age, and other clinical factors. Most experts consider bisphosphonates warranted for those with a risk of hip fracture ≥3.0% or combined major osteoporotic fracture ≥20%.
(Choice B) Menopausal hormone therapy is indicated for significant vasomotor symptoms (eg, hot flashes) in women with no contraindications (eg, breast cancer, venous thromboembolism). Although estrogen has benefits for maintaining bone density, bisphosphonates are preferred for initial treatment of osteoporosis or osteopenia with high fracture risk.
(Choice C) Bone turnover markers (eg, bone-specific alkaline phosphatase, propeptide of type I procollagen) correlate with the rate of bone loss and risk of fracture. However, their clinical use in osteoporosis is complicated by biologic variability and lack of standardization. Fracture risk is better estimated using the FRAX calculator.
(Choice D) Bisphosphonates have little benefit for patients with osteopenia at low fracture risk and carry certain risks (eg, jaw osteonecrosis, pill esophagitis). Therefore, fracture risk should be assessed before determining the need for treatment.
(Choice E) Frequent (eg, at 6-month intervals) bone density testing is recommended for patients with unusually rapid bone loss (eg, systemic glucocorticoid therapy). When follow-up testing is needed for patients with postmenopausal bone loss, a 2-year interval is generally appropriate.
Educational objective:
Patients with osteoporosis (T-score ≤−2.5 or osteoporotic fracture) warrant antiresorptive therapy; bisphosphonates (eg, alendronate) are first-line treatment for most patients. For patients with osteopenia (T-score between −1.0 and −2.5), the 10-year fracture risk can be calculated using the Fracture Risk Assessment Tool (FRAX) to determine if antiresorptive therapy is indicated.