From the FDA Drug Label
The skeletal effects of teriparatide depend upon the pattern of systemic exposure. Once-daily administration of teriparatide stimulates new bone formation on trabecular and cortical (periosteal and/or endosteal) bone surfaces by preferential stimulation of osteoblastic activity over osteoclastic activity In humans, the anabolic effects of teriparatide manifest as an increase in skeletal mass, an increase in markers of bone formation and resorption, and an increase in bone strength
The next steps for an 86-year-old man with osteoporosis, a T score of -2.9 at the femoral neck, and elevated Parathyroid Hormone (PTH) levels could be to consider treatment with teriparatide to stimulate new bone formation and increase bone strength. However, it is essential to note that the patient's elevated PTH levels should be evaluated and managed accordingly, as teriparatide is a recombinant human parathyroid hormone analog.
- The patient's age and renal function should also be considered, as the drug label notes that no overall differences in safety or effectiveness have been observed between patients 65 years of age and older and younger adult patients, but patients with severe renal impairment may have increased exposure to teriparatide 1.
- The patient's bone health and osteoporosis should be monitored closely during treatment with teriparatide.
From the Research
The next step for this 86-year-old man with osteoporosis and elevated PTH should be evaluation for primary hyperparathyroidism, and treatment for osteoporosis should be initiated with a bisphosphonate, calcium supplementation, and vitamin D, considering the high fracture risk and potential for normocalcemic hyperparathyroidism to contribute to bone loss. This approach is supported by the need to address both the potential underlying cause of the elevated PTH and the high risk of fractures associated with osteoporosis, as indicated by a T score of -2.9 at the femoral neck 2.
Given the patient's age and the presence of osteoporosis, it is crucial to consider the most effective and safest treatment options. The use of bisphosphonates, such as alendronate 70mg weekly or zoledronic acid 5mg IV annually, is a common approach for treating osteoporosis, especially in patients with a high risk of fractures 2. Additionally, ensuring adequate calcium and vitamin D supplementation is essential for bone health, with recommended daily intakes of 1000-1200mg of calcium and 800-1000 IU of vitamin D 3, 2.
The evaluation for primary hyperparathyroidism should include serum calcium measurements on multiple occasions, 24-hour urine calcium collection, and possibly parathyroid imaging studies if hyperparathyroidism is confirmed. The presence of elevated PTH with normal calcium levels suggests the possibility of normocalcemic hyperparathyroidism, which can contribute to bone loss and should be further investigated 4, 5.
Referral to an endocrinologist and possibly a parathyroid surgeon would be appropriate if primary hyperparathyroidism is confirmed, as treating the underlying condition may improve bone density. It is also important to consider secondary causes of elevated PTH, such as vitamin D insufficiency, chronic kidney disease, or medication effects, although vitamin D levels appear normal in this case 3, 6.
In terms of specific treatment for osteoporosis, the choice between available options, including bisphosphonates and potentially anabolic therapies like teriparatide, should be based on the patient's overall health status, fracture risk, and potential side effects of the medications 2. The most recent and highest quality evidence should guide the decision-making process, prioritizing the patient's morbidity, mortality, and quality of life outcomes.