With updated guidelines released in 2024, four experts clear up some confusing areas of osteoporosis and osteopenia treatment.

Myth: MHT is less effective than other osteoporosis therapies

Fact: MHT is as effective for preventing fractures as other anti-resorptive drugs

“MHT has the same magnitude fracture reduction as other common drugs I use, so bisphosphonates and denosumab,” says rheumatologist Professor Peter Wong, Medical Director and Chair of the Healthy Bones Australia Medical & Scientific Advisory Committee and Chair of the Guidelines Review Committee.

Professor Bronwyn Stuckey, consultant endocrinologist at Sir Charles Gardner Hospital, Medical Director of the Keogh Institute for Medical Research and Clinical Professor in the University of Western Australia’s medical school, agrees.

She cites research that looked at “all the potent anti-resorptive therapies, and showed that oestrogen therapy stacks up against all of them.”

So, are there any differences?

Dr Sonia Davison, lead endocrinologist at Jean Hailes for Women’s Health and Past President of the Australasian Menopause Society, says menopausal hormone therapy and tibolone are as effective as bisphosphonates, denosumab and teriparatide for preventing vertebral fractures. For hip fracture prevention, MHT, bisphosphonates and denosumab are effective, while tibolone is not as effective, she adds.

Myth: It’s okay to delay a denosumab dose

Fact: Denosumab must be administered every six months without delay

Professor Wong explains that unlike bisphosphonates, which kill osteoclasts, denosumab “just sends them to sleep.”

“So you’ve got this pool of osteoclasts that will come screaming back the moment you stop the denosumab, so you actually get enhanced bone resorption. And it’s well recognised now there is a risk of rebound vertebral fractures, often multiple,” Professor Wong says.

Healthy Bones Australia recommends that patients who miss their six-monthly injection should get it as soon as practical—preferably within four to six weeks of the missed dose.

If you know patients will miss a dose (e.g. if they’re going overseas), Professor Stuckey advises erring towards giving it early rather than delaying it.

Practice tip: You do not need to test calcium, vitamin D and renal function before every denosumab injection, Professor Stuckey says. Testing is recommended before initiating treatment, and repeat testing every one to two years is reasonable.

Myth: You can have a drug holiday from denosumab

Fact: Drug holidays are possible with bisphosphonates but not denosumab

Professor Wong explains that bisphosphonates have an in vivo half-life of years, so a drug holiday may be possible in some circumstances.

“If someone’s been on a bisphosphonate for, say, five years and you stop it, it’s going to have an in vivo effect for, depending on the bisphosphonate, probably a couple more years. So if you’ve successfully moved someone out of the osteoporotic range—maybe they’re in the mildly osteopenic range—and you want to stop a bisphosphonate, that’s probably okay.”

“And then you would monitor them with, say, a DXA scan every couple of years. If the BMD’s stable, that’s great. If the BMD falls or they have another fracture, then time to review.”

You cannot have a drug holiday with denosumab because of the rebound vertebral fracture risk, he stresses.

Myth: All older people should take calcium and vitamin D supplements

Fact: Supplementation is only advised in specific groups

While the guidelines note there is good evidence that adequate vitamin D status and calcium intake are important for maintaining bone and muscle function long-term, they do not recommend supplementation in generally healthy older people.

They do recommend routine calcium and vitamin D supplementation for frail older people living in nursing homes, along with adequate protein intake.

Supplementation is also advised in people being treated for osteoporosis if they get less than 1300 mg of calcium per day from their diet, or their serum vitamin D (25-hydroxyvitamin D) is less than 50 nmol/L.

Dr Davison says it’s better to get calcium from diet where possible. She recommends people check their intake using the table at Healthy Bones Australia.

“If they can only have 700mg through diet, just add one calcium supplement a day. That’s about 600mg, and then they’re covered.”

Vitamin D deficiency is common, and she aims for 75 to 125 nmol/L (or 50 as minimum), noting daily or weekly administration is appropriate.

Professor Stuckey stresses calcium and vitamin D supplementation alone is not sufficient to treat osteoporosis or osteopenia after menopause.

Myth: You need to run bone turnover markers before patients on osteoporosis drugs have a tooth extracted

Fact: This is not necessary

Dr Elliott says a lot of dentists ask for bone turnover markers before they’ll do an extraction, but there’s no point because it won’t change your management.

The guidelines recommend making sure patients at high risk of medication-related osteonecrosis of the jaw (MRONJ) get a dental review before starting osteoporosis medication. Bisphosphonates have a long half-life, they point out, so there is not much benefit to stopping them before a dental extraction. Patients on denosumab who need an invasive dental procedure should have it just before their next six-monthly injection, they advise.

Dr Davison says the risk of MRONJ is less than one in 1,400 for both bisphosphonates and denosumab, and atypical femoral fractures are also uncommon.

“Three per 10,000 after five years of bisphosphonate use and 13 per 10,000 after eight years of bisphosphonate use,” she says. “It’s higher in Asian women, higher in diabetes, with glucocorticoid use, and if they’ve had an atypical fracture before.”

Women should not avoid these medications because they’re worried about rare risks, she stresses. “We just need to counsel them appropriately and get advice from someone like me if you need it.”

Professor Wong asks people about their dental health and hygiene habits before initiating an intravenous bisphosphonate or denosumab.

“If there’s any issues, I get a friendly dentist to look at them first. For an oral bisphosphonate, I don’t bother because the risk is much lower.”

“If someone needs a dental extraction and they’re on a bisphosphonate, then it’s good dental hygiene, perioperative antibiotics for the extraction, and just wait and see. The risk is low.”

Professor Stuckey explains both MRONJ and atypical femoral fractures are linked with prolonged suppression of bone turnover—particularly of resorption—which can impact bone healing after a dental extraction or stress fracture.

She says patients who develop MRONJ may benefit from teriparatide and should be referred to a specialist.