A
presentation at the North American Menopause Society (NAMS) Annual Meeting in
Philadelphia October 11-14, will present
new evidence regarding long term safety and effectiveness of Bisphosphonates
and denosumab in treating postmenopausal osteoporosis.
According to International Osteoporosis Foundation, Osteoporosis is estimated to affect 200 million women worldwide -
approximately one-tenth of women aged 60, one-fifth of women aged 70,
two-fifths of women aged 80 and two-thirds of women aged 90.
Bisphosphonates
and denosumab are the most commonly prescribed treatments for osteoporosis.
There is no cure for osteoporosis and the effects of these drugs wear-off as treatment
ceases, hence prevention is the best bet.
As
Bisphosphonates therapy is started, protection from osteoporosis is gained in
first few months and persists as long as treatment is continued.
If
Bisphosphonate treatment is continued beyond 3 years, increasing risk of
unusual or “atypical” fractures of the femur (thigh bone) is observed. The risk
increases gradually as patient continue to take the drug beyond 3 years: the
risk is 20/100,000 patients at 5 years and 1/1,000 patients at 8-10 years.
If the drug
is stopped, protection from fractures is lost gradually in 3-5 years.
This
combination of increased risk of atypical fractures on continued treatment and
decline in protection from fractures as treatment is stopped led to the
confusing concept of a “bisphosphonate holiday.”
The American Society for Bone and Mineral Research (ASBMR) has recently provided clear
recommendations about “bisphosphonate holidays.”
ASBMR
recommends that, after 3-5 years of treatment with bisphosphonates, a patient risk
of fracture should be evaluated. If the patient remains at ‘high risk’ for
fracture because of low BMD, previous history of hip, spine, or multiple other
fractures, the treatment should not be stopped.
Patient can
continue the same treatment or change to some other drugs like denosumab.
Those
patients who are at ‘low risk’ for fracture, the treatment can be stopped for
3-4 years, but it is not mandatory.
The concept
of ‘drug holiday’ only holds good for Bisphosphonates only, and not for other
drugs like raloxifene, teriparatide, and denosumab because beneficial effects
of these drugs are lost as soon as they are stopped.
Dr. Michael
McClung of the Oregon Osteoporosis Center in Portland, Oregon, who will be
presenting his recommendations on long-term osteoporosis therapy at the NAMS
Annual Meeting said, “Because protection from fractures disappears quickly if
denosumab treatment is stopped, and since there are no currently known safety
issues that limit the duration of denosumab therapy, there is no justification
for a drug holiday with this treatment.”
“Just as we
do not recommend stopping treatment for high blood pressure or diabetes, it is
necessary to have a long-term treatment plan for postmenopausal women with
osteoporosis if the benefits of our therapies are to be realized,” he further
added.
Dr. JoAnn
Pinkerton, NAMS executive director said, “Prevention of osteoporosis should be
a goal for those treating menopausal women, as up to 20% of bone loss occurs
within the first five years of menopause. Once diagnosed with osteoporosis, the
goal becomes lowering the risk of fractures as fractures can be life changing
or life limiting. This presentation will offer valuable insights about the need
for long-term treatment and will change the way health care providers approach
long-term osteoporosis management.”
