Effective therapy is now available to safely and
simply treat osteoporosis while reducing your
risk of fracture. The following is a list of the
most widely used treatment options.
Bisphosphonates
(alendronate,
risedronate, etidronate)- Bisphosphonates are
compounds that bind specifically to bone and inhibit
osteoclast (cells responsible for break down of
bone) function. These compounds are used to increase
bone mineralization/density (bone thickness and
strength).
Etidronate
(Didrocal): The first bisphosphonate developed
for the prevention and treatment of osteoporosis.
Etidronate was shown to be effective in decreasing
vertebral fractures in postmenopausal women with
osteoporosis. There is no evidence indicating
that etidronate has a beneficial effect on prevention
of hip or non-vertebral fractures. Etidronate
must be taken in three month cycles if taken continuously
for a prolonged period of time individuals may
have an increased risk of developing osteomalacia
(softening of the bone). Evidence regarding the
effectiveness of etidronate in the prevention
of non-vertebral (spine) fractures is weak, thus
it is generally considered a second line treatment.
Etidronate is however cheap, and covered by most
provinces’ drug benefits plans.
Alendronate
(Fosamax): Alendronate is a highly potent bisphosphonate.
It is effective in preventing vertebral (spine),
hip, and non-vertebral fractures. In a recent
study alendronate was found to decrease new vertebral
(spine) fractures by 90% while decreasing the
incidence of new hip fractures by 63%. Alendronate
has a rapid anti-fracture effect and is a generally
safe and well-tolerated medication. It is important
that patients take alendronate and other bisphosphonates
on an empty stomach (at least 30 minutes before
the first food of the day) because a very small
amount of the drug is actually absorbed.
Risedronate
(Actonel):an amino-bisphosphonate shown to effectively
and safely prevent vertebral and non-vertebral
fractures. Risedronate has a rapid anti fracture
effect. Given over a period of 12 months risedronate
was shown to reduce vertebral fractures by 61%-65%.
Risedronate may be taken once weekly at a dose
of 35mg. The effect of risedronate on hip fractures
in elderly women was specifically evaluated in
a study known as HIP or the Hip Intervention Program.
A significant reduction in the occurrence of hip
fractures was seen in women with osteoporosis.
Risedronate is available in both a once daily
dose (5 mg) as well as a once weekly dose (35
mg). Once weekly risedronate therapy has comparable
effects to once daily risedronate therapy. Risedronate
is a safe and well-tolerated medication. Dosing
instructions are similar to alendronate. Risedronate
is more expensive that etidronate and not covered
on all provinces’ drug benefit plans. For
more information please visit www.betterbones.ca
Selective
Estrogen-Receptor Modulators (SERM’s)
Raloxifene
(Evista): raloxifene is a once daily therapy (60
mg per day) indicated for the treatment and prevention
of postmenopausal osteoporosis. In recent studies
raloxifene has been shown to reduce new vertebral
fractures by 55% after 3 years of treatment. Raloxifene
has a
rapid anti fracture effect in those individuals
who have been diagnosed with osteoporosis. Roloxifene
was shown to decrease the likelihood of vertebral
fractures by 68% in as little as 12 months. Currently,
raloxifene has not been shown to prevent non-vertebral
fractures. The Multiple Outcomes of Raloxifene
Evaluation (MORE) study was not designed to evaluate
the effectiveness of raloxifene on non-vertebral
fractures.
Participants of the MORE study were younger and
had less severe osteoporosis than patients in
other trials. Women were withdrawn from the MORE
trial if they had excessive bone loss. These factors
may have contributed to the very few hip fractures
seen in the study. Raloxifene may be used in combination
with amino-bisphosphonates such as alendronate
or risedronate for patients at risk of hip fractures.
Raloxifene has many added extra-skeletal benefits.
In the MORE trial the use of roloxifene was shown
to lower both total and LDL cholesterol (bad cholesterol),
fibrinogen, lipoprotein A, and homocystine levels.
In the MORE trial it was determined that cardiac
events (heart attacks) were reduced by 40% in
women at an increased risk of heart disease. Additionally
raloxifene was shown to significantly reduce the
occurrence of breast cancer by 84%. Those individuals
who have a history of thrombosis (blood clots)
should not take raloxifene
Calcitonin
Miacalcin:
Salmon calcitonin is effective in the treatment
and management of osteoporosis and in particular
pain following a fracture. Calcitonin may be delivered
as either a nasal spray or injection. The effects
of nasal calcitonin in varying doses were studied
in a recent research study entitled The Prevent
Recurrence of Osteoporotic Fractures (PROOF) study.
Risk of vertebral fracture was significantly reduced
with the 200-IU/day dose, but not with the 100-IU/day
or 400-IU/day doses. Calcitonin was found to reduce
the risk of new vertebral fractures by 62% in
osteoporotic women over the age of 75.
Side effects of Calcitonin treatment were limited
to rhinitis (runny nose). Calcitonin has no negative
effects on bone mineralization and is the preferred
method of treatment in patients with osteomalacia,
renal, or liver diseases. Calcitonin is of significant
benefit to patients with gastrointestinal symptoms
such as acid reflux and are unable to tolerate
oral bisphosphonates. Calcitonin is most commonly
used for the treatment and management of osteoporosis
in postmenopausal women. Due to its extremely
safe side effect profile calcitonin can be used
in premenopausal women who are planning a future
pregnancy. Calcitonin is often used to treat and
manage bone pain associated with vertebral fractures.
It is possible to use Calcitonin in combination
with other medications.
Hormone Replacement
Therapy (HRT)
HRT has been
shown to reduce the risk of fractures in postmenopausal
women. In the Women’s Health Initiative
trial (WHI) 16,608 postmenopausal women aged 50-79
received 0.625 mg of conjugated equine estrogen
with 2.5 mg of medroxyprogesterone acetate or
placebo (water pill) daily. After 5.2 years of
treatment vertebral and hip fractures were reduced
by 34%. However HRT was associated with a 29%
increased risk of developing a cardiac event,
a 41% increased risk of stroke, patients were
twice as likely to experience an embolism (blood
clot) and demonstrated a 26% increased risk of
breast cancer. Benefits did include a 37% decrease
in colorectal cancer. Patients at increased risk
of breast cancer, heart disease, stroke, or thromboembolic
events (blood clots) should be cautioned against
use of HRT. In the WHI the overall benefits of
HRT were outweighed by the overall risks. Discuss
the use of HRT with your physician.
:
Osteoporosis is an area of active investigation
and discovery. The most recent discovery for the
treatment of Osteoporosis is a drug known as parathyroid
hormone.
Parathyroid
Hormone (PTH): PTH is the only treatment
that has been shown to actually build new bone.
Recent studies evaluating the effectiveness of
PTH have shown significant increases in new bone
formation (7%-10% per year).PTH is actually able
to reverse the deterioration of bone quantity
and quality that was once believed to be irreversible.
In a 21-month study conducted to determine the
effectiveness of PTH it was shown to reduce the
risk of vertebral fractures by 65% and 69% and
the risk of non-vertebral fractures by 53% and
54% while using a 20-ug daily and 40ug daily dose
respectively. Increases in bone density in men
have also been seen with PTH therapy. PTH has
received FDA (Food and Drug Administration) approval
in the United States and has also been approved
in Canada. PTH. Side effects include nausea and
headache. PTH is administered for 18 months and
can be followed by other anti-resorptive agents.
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