Treatment is only indicated for patients with a Bone Mineral Density showing osteoporosis (T score of worse than -2.5). Although osteopenia (T score -1 to -2.5) is a risk factor for future fracture, there are currently no trials showing benefit of treatment in these patients as a group.
The following general recommendations for the treatment of osteoporosis including, secondary prevention of fragility fracture are currently considered 'best practice'. This is not a comprehensive clinical treatment guideline. Seek advice if unsure via Nicola Ward, Fracture Prevention Service, BOPDHB, 07 557 5570 or 027 8013 723.
For all situations listed below, ensure adequate calcium and vitamin D intake.
Bisphosphonate is recommended unless contraindicated (or considered inappropriate for other reasons e.g. limited life expectancy).
Choose any one of Risedronate (no special authority required), Alendronate, Zoledronic acid
(see below for differentiating factors). Etidronate is no longer recommended.
NB: Pharmaceutical manufacturers of bisphosphonates do not recommend bisphosphonates if calculated creatinine clearance (Cockroft and Gault) <30ml/min (risedronate) or <35ml/min (alendronate, zoledronic acid).
If a patient experiences a further fracture on anti-osteoporosis treatment, it is not necessarily an indication that the treatment should be changed or discontinued. Check adherence and exclude secondary causes of osteoporosis. Decision to continue or change treatment may be influenced by a number of factors including length of time patient has been on treatment and degree of worsening of BMD measurements. Consult if unsure, via HIA e-Referral or contact Fracture Prevention service as above.
How to choose between bisphosphonates?
The following three bisphosphonates have similar licensed indications. The evidence base differs for each one but a class effect is generally assumed.
*Find the 'Alendronate Tab 70 mg - with or without Cholecalciferol' Special Authority Form under the 'Musculoskeletal System' heading on the Pharmac 'Special Authority Forms' webpage.
**Find the 'Zoledronic acid inj 0.05 mg per ml, 100ml' Special Authority Form under the 'Musculoskeletal System' heading on the Pharmac 'Special Authority Forms' webpage.
Treatment duration & drug holidays:
Treatment review is essential as there may be an increased incidence of rare adverse effects with long-term bisphosphonate use. Review risedronate and alendronate after 5 years and zoledronic acid after 3 years.
After a total of 10 years for risedronate and alendronate or 6 years for zoledronic acid, stop bisphosphonate but continue adjunctive therapies i.e. vitamin D, dietary advice, falls prevention.
When treatment is discontinued, fracture risk should be reassessed every two years or after a new fracture (regardless of when this occurs).
Second Line Therapy
Teriparatide is a fragment of parathyroid hormone, administered by once-daily subcutaneous injection, that may be used in patients with established osteoporosis and recurrent fracture and following at least 12 months of antiresorptive therapy.
Denosumab is a monoclonal antibody directed against RANK-ligand, administered by subcutaneous injection every 6 months, for treatment of osteoporosis. Denosumab is not yet reimbursed in New Zealand.
Selective estrogen receptor modulators (SERMS)
SERMS (e.g. raloxifene) could be considered as an alternative to oestrogen therapy in postmenopausal women, although raloxifene does not prevent hip or other non-vertebral fractures.
Strontium ranelate is not recommended because of its adverse cardiovascular profile.
If considering treatment with Teriparatide please ensure patient meets Pharmac special authority criteria*** for eligibility, and if the patient is eligible refer to the Fracture Prevention Service via Health in Ageing eReferral (Annotate referral with Fracture Prevention Service).
***Find the 'Teriparatide' Special Authority Form under the 'Musculoskeletal System' heading on the Pharmac 'Special Authority Forms' webpage.
Disclaimer: This site is intended to be flexible and frequently updated. While every effort has been made to ensure accuracy, all information should be verified.