OSTEOPOROSIS IN OLDER WOMEN: PRACTICAL APPROACHES
From Johns Hopkins University School of Medicine’s Current Topics in Geriatrics
| OLD BONES: WHAT’S NEW —Michele F. Bellantoni, MD, Associate Professor of Medicine, Division of Geriatric Medicine
and Gerontology, Johns Hopkins University School of Medicine, Baltimore, MD
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| Screening for osteoporosis: risk factors—female sex; with age, increased risk for fracture; osteoporosis, in clinical terms,
means risk for clinically significant fracture (impairs mobility; causes pain, kyphosis, and deformity); family history (hip
fracture in parent key); behaviors, including alcohol abuse, phosphate-containing beverages (cause calcium malabsorption),
immobility, and tobacco use; premature menopause from surgery, autoimmune conditions and chemotherapy; medical
conditions—eg, rheumatoid arthritis (steroid use and underlying inflammatory processes impair bone metabolism), thyroid
disease (untreated hyperthyroidism causes active bone resorption; overreplacement with thyroxine causes accelerated
bone loss); celiac disease (15% of celiac patients have severe osteoporosis as only clinical manifestation; consider in “idiopathic
osteoporosis”; screen with serum test for endomysial antibodies); spectrum of gastrointestinal (GI) malabsorption;
age-related vascular disease (associated with renal insufficiency and diabetes); hyperparathyroidism (condition of aging; serum
calcium often high normal initially, but later marked hypercalcemia develops in setting of dehydration; manage with
bisphosphonates to halt rapid bone loss); myelomas (primarily cancer of aging; symptoms chronic fatigue, weight loss, diffuse
osteoporosis, and pathologic fractures); medications—phenytoin impairs vitamin D metabolism (manage with aggressive
vitamin D repletion [1000 to 1200 IU daily]); chemotherapies, including breast and prostate cancer therapies; aromatase
inhibitors (cause bone loss)
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| Assessing bone health: bone densitometry—standard of practice; bone mass best predictor of fracture, and screening part of
preventive health care; looking at lumbar spine and hip; in lumbar spine, must include ≥2 vertebrae to obtain accurate assessment;
deformed vertebrae in degenerative spine disease, particularly in posteroanterior image, must be excluded from interpretation;
if >1 SD difference between consecutive vertebrae, one that looks deformed must be excluded; if unable to get 2
vertebrae, cannot interpret spine; challenge for provider to determine which numbers clinicially significant; fractured and collapsed
vertebrae very dense and must be excluded; focus on hip and femur neck; Ward’s area has lowest bone mineral density
(BMD) in hip (does not predict fracture); forearm sites (quick and easy to scan; positioning simple); Medicare reimbursement
allows for hip and spine together (central bone density) or separate code for forearm; computed tomography (CT)—not approved
by Food and Drug Administration (FDA) for monitoring rate of change; radiation and cost high; dual-energy x-ray
absorptiometry (DEXA)—Medicare reimbursement $150; most cost-effective; portable DEXA device for forearm for use
in health fairs and ultrasonography for heel useful screening tools; caveats—because of discordance of bone loss with aging,
young adult may begin to lose BMD vertebral body before forearm or heel (less trabecular bone, more cortical bone and more
dense compacted bone); DEXA technology limited (unable to obtain architecture of bone); bone strength not measure of density,
just its architecture; microscopic CT and magnetic resonance imaging on horizon; DEXA not effective for monitoring
change; when obtaining DEXA, need to see images before deciding that screen useful; deformed spine cannot be read (vertebral
bodies must be straight, reasonably shaped, and without heavy density); in hip, part of lesser trochanter must be visible; if
hip not positioned same way from one scan to next, can get different BMD; BMD is ratio (numerator bone mineral content,
and denominator area of bone being measured; area of bone measured changes when hip repositioned); femoral neck box and
area of interest must be positioned similarly; patient with severe osteoarthritis can still have BMD of hip measured (challenge
measuring rate of change)
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| World Health Organization (WHO) definitions: T and Z scores used in report; T score—comparison of patient’s BMD
with normal peak BMD; each bone site has different peak (in general, at 25-30 yr of age); osteopenia—T score -1 to 1 SD
below normal to -2.5 SD; osteoporosis—T score <-2.5 SD; numbers developed before bisphosphonate therapy and before
better understanding of epidemiology of fractures for age and medical conditions that affect fracture; T score should not be
only consideration for when to treat and how to manage condition; Z score—comparison of patient’s BMD with people of
same age; useful to determine need for extensive evaluation for secondary causes of osteoporosis, eg, Z score <-1.5 to -2 SD,
consider vitamin D deficiency or celiac disease; take-home message—WHO definitions of osteopenia and osteoporosis
based on DEXA no longer determine when to treat with prescriptive therapies (eg, bisphosphonates); 50% of fractures occur
in women whose DEXA results show osteopenia
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| Interpretation of DEXA: age biggest factor (for same BMD, 55-yr-old and 75-yr-old have different absolute fracture risk,
with older adult having almost double fracture risk); report forthcoming on how to predict absolute fracture risk, considering
BMD, age, corticosteroid use, prevalent adult fracture, and parent with hip fracture; pitfalls in interpretation—
spine may have falsely elevated BMD due to degenerative processes of aging and vertebral compression; consider clinical
history—height loss >1.5 in clinically significant; usually due to degenerative spine disease, not osteoporosis, but
consider osteoporosis and asymptomatic vertebral compression factures; assessment of vertebral fractures—now approved
by Medicare for reimbursement under certain clinical guidelines (height loss, history of fracture, or T score within
range for osteopenia or osteoporosis); consists of lateral image of spine with computer algorithm to predict fracture, primarily
anterior compression of vertebral bodies; assessment required upgrading of DEXA machines, causing changes in
BMD for spine, hip, and forearm; consider first reading from upgraded machine new baseline; information about change
in machine should be provided in report; serial DEXA—perform baseline and follow-up on same machine; look for
change in absolute BMD, not T scores (upgrades to software change normative database and T scores); rate of change
based on absolute BMD; significant change 3% (each device and center different); clinically important in serial BMD is
whether progression of loss halted, not increasing BMD; with bisphosphonate therapy, fracture reduction equal, whether
BMD same or increased; BMD decrease should prompt medical evaluation for underlying cause; number one cause in
older adults vitamin D deficiency
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| Screening guidelines and recommendations: standard of care for preventive practice—United States Preventive Services
Task Force (USPSTF) recommends DEXA as part of clinical practice for all women >65 yr of age and women 60
yr of age with risk factors; treat asymptomatic women with low BMD with goal of reducing risk for fracture; National
Osteoporosis Foundation—currently recommends treatment with bisphosphonates if T score -2 to -1.5 SD below normal
with risk factors ( recommendation changing, so look at absolute risk); also screen all men 70 yr of age; for man with
height loss of 1.5 in or 70 yr of age, single DEXA reasonable preventive health measure; fracture is clinical issue that
should prompt DEXA; also screen adults with high-risk medical conditions (eg, celiac disease)
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| Medical evaluation for underlying cause: physical examination—body habitus for leanness; reproductive health; diet
(phosphate-containing beverages, alcohol, and caffeine); medications; physical activity (immobility causes rapid bone
loss); diagnostic studies—basic (serum calcium, 25 vitamin D level in adults who do not have renal failure, parathyroid
hormone [PTH]); bone biomarkers not useful, except in setting of rapid bone turnover (hyperthyroidism or hyperparathyroidism);
in GI malabsorption, check for vitamin D and PTH (often elevated; secondary hyperparathyrodism); in renal
failure, check 1,25 dihydroxy vitamin D level (active form of Vitamin D)
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| Management: nutrition key; calcium (1500 mg daily) and vitamin D supplementation (800 IU daily); recommend usual
healthy diet, not aggressive supplementation; folic acid; physical activity (to prevent fragility fractures and nerve damage);
based on data from Women’s Health Initiative, can no longer recommend estrogen for bone health; prevention in
osteopenic 50-yr-old woman, drug therapy for osteoporosis; mainstay bisphosphonates with calcium and vitamin D; intravenous
(IV) bisphosphonates undergoing clinical trials (concern about renal toxicity); need interdisciplinary approach
to osteoporosis (nutrition and management of pain and immobility; primary care provider in lead for screening and treatment)
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| PANEL DISCUSSION —Colleen Christmas, MD, Assistant Professor of Medicine, Johns Hopkins University School of
Medicine, Baltimore, MD, and Dr. Bellantoni
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| Repeat DEXA once patient established on bisphosphonate: 2-yr interval for BMD testing recommended for postmenopausal
women on drug therapy; aime for no loss of BMD (not gain); no randomized controlled trial showing one bisphosphonate
better than others
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| Results of DEXA performed at different times: issue of different devices, different operators, and not attentively positioning
bone sites of interest; for well trained operators who understand positioning, error rate 3%; if operator does not understand
importance of positioning and does not calibrate machine before starting day, error much greater
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| When to stop drug therapy in patients near end of life: bisphosphonates show reduction in vertebral fractures of 50% at
12 mo (in studies performed on ambulatory patients); nursing home patients different cohort; consider patient’s entire
clinical picture, including comorbidities and functional status; speaker recommends minimal supplementation for nursing
home and ambulatory population (provide calcium in diet)
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| DEXA for younger lean woman: USPSTF guidelines for screening; not routinely done in women until age 65 yr or age 60
yr if with risk factors; fracture in adult raises clinical suspicion for osteoporosis; normal bone should not fracture from
fall at ground level (suggests fragility of bone); evidence that patients with osteoporosis and fracture undertreated and
sustain subsequent fractures; once patient has fracture, start on bisphosphonates, calcium, vitamin D, and exercise
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| When to repeat DEXA in patients 65 yr of age with normal BMD: no medical literature to guide decision; if individual’s
health not changed, speaker would not perform DEXA for at least 5 yr, but checks patient’s height yearly as vital sign
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| Side effects of bisphosphonates: osteonecrosis of jaw reported but uncommon (primarily seen after dental procedures)
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| Low testosterone in men with osteoporosis: no evidence that replacing testosterone reduces risk for fracture; testosterone
not FDA-approved for bone health
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| Intolerance to bisphosphonates in patients with significant osteoporosis: speaker looks at clinical outcome of fracture (not
BMD alone) to make decision; speaker uses subcutaneous parathyroid derivatives in patients with multiple fractures who
are intolerant to bisphosphonate or continue to fracture on bisphosphonate; FDA approval for parathyroid derivative limited
to use for 2 yr
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| Patient with >3% decline in DEXA score: already on bisphosphonate, calcium, and vitamin D with other causes (eg, celiac
disease) ruled out; speaker analyzes scores to ensure DEXA truly showing loss; speaker often finds DEXA not well done
or not comparably positioned; when continued loss seen, usually see vitamin D deficiency, evidence of malabsorption, or
improper (eg, postprandial) dosing of bisphosphonates; speaker continues therapy, even if she thinks DEXA data inaccurate,
but switches to subcutaneous parathyroid derivatives if therapy ineffective and degree of osteoporosis significant
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| Role of combination of bisphosphonates with calcitonin-salmon (Miacalcin) or raloxifine: no data to support use of combination
of antiresorptive agents for prevention of fractures (combination therapy not recommended); trial of combination
of subcutaneous parathyroid derivatives with bisphosphonates under way, but BMD data insufficient for clinical
practice recommendations
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| IV bisphosphonates: FDA reviewing data soon; speaker not switching average patient from oral to IV bisphosphonates because
of case reports of renal insufficiency; continue oral therapy if patient tolerating it well; also no data yet as to whether
IV bisphosphonates can cause osteonecrosis; speaker more comfortable using oral bisphosphonates initially; speaker
would use IV bisphosphonate in tertiary referral population, ie, individuals with significant GI disorders and severe osteoporosis,
where aggressive vitamin D and calcium repletion used
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| Work-up for vitamin D in renal insufficiency: speaker obtains 1,25 dihydroxyvitamin D level when renal insufficiency requires
referral to nephrologist or creatinine clearance <30 mL/min
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| Recommendations for vitamin D repletion: controversial, even as to amount to give healthy aging adult and how to replace
in deficiency; small amount of literature suggesting that more intensive dosing (10,000 to 50,000 IU of ergocalciferol
weekly for 4 wk) achieves desired level faster; can then replete with 800 IU of cholecalciferol daily
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| Testosterone replacement and BMD outcomes: small trials under way, but most do not show benefit from testosterone;
unlikely to find benefit in prevention of fractures; some good data in one trial (Orwoll 2000) showing alendronate in men
has benefit similar to that of bisphosphonates in women
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| Duration of bisphosphonate therapy: clinical trials under way to determine duration (no definitive answer yet); early literature
from company-sponsored open-label studies shows continued fracture benefit at 10 yr
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| Renal function threshold for bisphosphonates: oral form contraindicated when creatinine clearance <30 mL/min and in
renal dialysis patients (oral and IV forms); be aggressive with calcium and vitamin D; speaker has used selective estrogen
receptor modulators (SERMs) in very limited manner because of vascular issues; can also use calcitonin; PTH contraindicated
in patients with renal failure because they often have secondary or tertiary hyperparathyroidism
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Educational Objectives
| The goal of this program is to educate the listener about the risk factors, screening, diagnosis, prevention, and treatment of
osteoporosis. After hearing and assimilating this program, the clinician will be better able to:
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 | 1. Assess patients for risk factors for osteoporosis.
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| 2. Interpret dual-energy x-ray absorptiometry (DEXA) scores to determine bone mineral density (BMD).
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| 3. Cite the World Health Organization definitions of osteopenia and osteoporosis.
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| 4. Discuss the United States Preventive Task Force and National Osteoporosis Foundation screening guidelines and recommendations.
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| 5. Implement optimal prevention and treatment strategies for patients at risk for, or with established, osteoporosis.
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\Discussed on This Program
Alendronate sodium [Fosamax]
Alendronate sodium/cholecalficerol [Fosamax Plus D]
Calcitonin-salmon [Miacalcin, others]
Calcium [several formulations and trade names]
Ergocalciferol (D2 ) [Calciferol Drops, Drisdol, Drisdol Drops]
Etidronate disodium [Didronel, Didronel IV]
Folic acid (folacin; pteroylglutamic acid; folate) [Folvite]
Levothyroxine sodium (T4 ; L -thyroxine) [several trade names]
Phenytoin [Dilantin Infatab, Dilantin-125]
Raloxifene [Evista]
Risedronate sodium [Actonel]
Risedronate sodium and calcium carbonate [Actonel with Calcium]
Teriparatide acetate (rDNA origin; parathyroid hormone) [Forteo]
Testosterone (several formulations and trade names)
Vitamin D
Suggested Readings
Asomaning K et al: The Association between Body Mass Index and Osteoporosis in Patients Referred for a Bone Mineral
Density Examination. J Womens Health (Larchmt) 15:1028, 2006; Bobba RS et al: Tolerability of different dosing regimens
of bisphosphonates for the treatment of osteoporosis and malignant bone disease. Drug Saf 29:1133, 2006; Bolland
M et al: Osteonecrosis of the jaw and bisphosphonates--putting the risk in perspective. N Z Med J 119:U2339, 2006; Davis
GC et al: A bone health intervention for older adults living in residential settings. Res Nurs Health 29:566, 2006; Lane N:
Osteoporosis—is there a rational approach to fracture prevention? Bull Hosp Jt Dis 64:67, 2006; Nohara T et al: Accelerated
decrease in bone mineral density in women aged 52-57 years. Tohoku J Exp Med 210:341, 2006; Orwoll E et al: Alendronate
for the treatment of osteoporosis in men N Engl J Med 343:604, 2000; Spencer EH et al: Vitamin and mineral
supplement use among US medical students: a longitudinal study. J Am Diet Assoc 106:1975, 2006; Vestergaard P: Current
pharmacological options for the management of primary hyperparathyroidism. Drugs 66:2189, 2006;
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial relationship
with the manufacturer or provider of any commercial product or service discussed. For this issue, the faculty reported
nothing to disclose.
Drs. Bellantoni and Christmas spoke at the Johns Hopkins University School of Medicine’s Current Topics in Geriatrics,
held February 9-11, 2006, in Baltimore, MD, and sponsored by the Johns Hopkins University School of Medicine. The Audio-Digest
Foundation thanks the speakers and the sponsor for their cooperation in the production of this program.
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