This
month we review information related to osteoporosis and what options
women have.
Osteoporosis vs. Osteopenia
Osteoporosis is a disease in which the bones become extremely
porous (at least 70% bone loss in order to be detected on routine
chest films or spinal X-rays), and are subject to fracture. These
bones heal slowly and it occurs especially in women following
menopause and often leads to curvature of the spine from vertebral
collapse. Osteopenia is a clinical condition whereby the generation
of new bone material is insufficient to compensate for normal bone
loss. Osteopenia can be reversed more easily and responds well to
weight bearing exercise and calcium/vit D supplementation (if there
are no metabolic causes).
Diagnostic procedures used to determine bone loss include DEXA
(Dual Energy X-Ray Absorptiometry) more commonly known as a bone
scan test or densinometric CT scan.
Health Tips
Research has identified risk factors that commonly effect post
menopausal women. These include:
-Cigarette smoking
-Alcohol abuse
-Physical inactivity
-Thin habitus
-Diet low in calcium
-Little exposure to sunlight
-Glucocorticoids (7.5 mg/day or more of prednisone for more than 6
mo)
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OSTEOPOROSIS
There has been quite a bit of discussion in the medical literature
and the popular health media about a common bone condition that
primarily affects post menopausal women but can in fact be a problem
for a larger segment of the population. Recent literature has
suggested that even men aged 31 to 87 years can benefit from
pharmacologic intervention to combat osteoporosis.(1) But is it
necessary? To help put things into perspective, we have reviewed
articles published in respected, peer-reviewed, health and medical
journals.
BACKGROUND
In order to gain an understanding of the current concepts in
osteoporosis there are a few terms that need to be described.
Common drugs used to treat osteoporosis include:
Alendronate Sodium,
more commonly known as "FOSAMAX" exists as 10
mg oral. It has been associated with esophagitis and upper GI
upset with an increase in acid reflux symptoms.
Etidronate Disodium,
more commonly known as "DIDRONEL" exists as
400 mg oral. More commonly used in the treatment of moderate to
severe symptomatic Pagets disease of bone. Symptoms
include diarrhea, loose stools, nausea, GI upset, abdominal
discomfort, vomiting and occult blood in stools.
Taken from the
American Hospital Formulary Service Drug Information.
MISCONCEPTIONS OF OSTEOPOROSIS THERAPY.
Most drugs used to treat osteoporosis are termed antiresorptive
drugs. This term misleads as bisphosphonates (DIDRONEL AND FOSAMAX),
actually promote both resorption and bone formation because the two
processes are actually tied together. When the antiresorptive drugs
are given, the rate of bone resorption decreases within weeks but
the rate of bone formation also decreases months later. This
difference in timing is considered the remodeling space. This is why
most bisphosphonate drugs must be combined with Vit D, calcium and
calcitonin to be maximally effective. Some drugs act by increasing
bone formation which include fluoride and intermittent parathyroid
hormone, but they can also increase symptoms of bone pain and induce
hypophosphatemia. The bone that is formed fills in cavities in the
bone that have been left behind by previous resorption.
ESTROGEN REPLACEMENT THERAPY
Hormone replacement therapy (HRT), has often been combined with
other forms of treatment for osteoporosis. Estrogen has been linked
to maintaining bone density in women.(2) Although estrogen
circulating in postmenopausal women is lower because of decreased
secretion from the ovaries (if they haven't been removed), it does
not mean that there can nothing done to prevent bone loss. Although
there has been concern that increasing a woman's exposure to
estrogen beyond menopause may increase the risk in breast cancer, a
study by Nguyen et al. has found that the use of estrogen in
osteoporosis treatment should not elevate the risk of breast cancer
to the level experienced by other non-osteoporotic postmenopausal
women.(3) Before older women begin receiving hormone-replacement
therapy, clinicians should inform them of the increased risk of
blood clots, gallbladder disease, urinary incontinence, and fatal
stroke.
THE BOTTOM LINE
Consult your primary care physician about the options you have
based on DEXA or CT scans of your bones combined with your
medical/physical history. If you feel that your options may not be
to your liking, consider weight bearing exercise (it's free), Vit D
taken with a good calcium supplement. And if you smoke, perhaps this
would also be a good time to quit!
(1) Eric Orwoll, Mark Ettinger, Stuart Weiss, Paul Miller, David
Kendler, John Graham, Silvano Adami, Kurt Weber, Roman Lorenc, Peter
Pietschmann, Kristel Vandormael, and Antonio Lombardi.
Alendronate for the Treatment of Osteoporosis in Men. NEJM 2000 Aug
31;343:604-610
(2) Garnero P, Sornay-Rendu E, Claustrat B, Delmas PD. Biochemical
markers of bone turnover, endogenous hormones and the risk of
fractures in postmenopausal women: the OFELY study. J Bone Miner Res
2000 Aug;15(8):1526-36
(3) Nguyen TV, Center JR, Eisman JA. Association between breast
cancer and bone mineral density: the Dubbo Osteoporosis Epidemiology
Study. Maturitas 2000 Jul 31;36(1):27-34
Additional
References
Hulley S, Grady D, Bush T, et al. Randomized trial of estrogen plus
progestin for secondary prevention of coronary heart disease in
postmenopausal women. JAMA 1998;280:605-613
Byers RJ, Hoyland JA, Braidman IP. Osteoporosis in men: a cellular
endocrine perspective of an increasingly common clinical problem. J
Endocrinol 2001 Mar;168(3):353-62
Hulka BS, Moorman PG. Breast cancer: hormones and other risk
factors. Maturitas 2001 Feb 28;38(1):103-13; discussion 113-6
Eastell R. Treatment of postmenopausal Osteoporosis. NEJM 1998 Jun
12;338(11):736-46