Osteoporosis

Dr. T. Joshi, MD

Osteoporosis is a silent disease until is complicated by fractures- fractures

occurring with minimal trauma or without any trauma

About 50% of white women and 20% of men will have an osteoporosis-related fracture in their lifetimes.

Kyphosis

KyphosisKyphosis with Hypogonadism

Three-dimensional micro-CT images of trabecular bone in the distal radius of a woman • with normal bone density (top) and• with osteoporosis (bottom). Note the thinning and loss of

trabeculae, which lead to loss of resistance to fracture

What is Osteoporosis ? • Low bone mass involving

trabecular bone microarchitecture and connectivity

• and a thinning of cortical bone,• Decreased bone strength and an

increased risk of fracture.

When is the peak bone mass ? • 20s and 30s. Then it declines.

Risk Factors:• Non Modifiable: Advanced age,

female sex, firs degree relative, white or Asian ancestry, and Postmenopausal

• Modifiable: Smoking, alcohol, low body weight, sedentary life style

• Conditions : Anorexia, copd, CKD, Hyperparathyroidism, Hypogonadism, monoclonal gammapathy, Intestinal Malabsorption, Rheumatoid Arthritis, Thyrotoxicosis

• Medications: Steroids, Carbamazepine, Depot medroxyprogesterone acetate, phenytoin, Leuprolide

Question:1• A 74-year-old woman is evaluated during a follow-up visit. One month ago, she was

diagnosed with giant cell arteritis and began treatment with prednisone, 60 mg/d. She also takes calcium and vitamin D (25-hydroxy vitamin D) supplementation.

• On physical examination, temperature is 37.0 °C (98.6 °F), blood pressure is 122/79 mm Hg, pulse rate is 66/min, and respiration rate is 12/min. BMI is 22. The remainder of the examination is unremarkable. Bone mineral density test results reveal a T score of -1.5 at the spine.

• In addition to tapering steroids, which of the following is the most appropriate treatment for the patient?

A) AlendronateB) CalcitoninC) Estrogen hormone replacement therapyD) Hydrochlorothiazide and sodium restrictionE) Substitute calcitriol (1,25-dihydroxy vitamin D) for vitamin D (25-hydroxy

vitamin D)

Explanation

• Answer: Alendronate• According to the recommendations of the American

College of Rheumatology, prevention of corticosteroid-induced osteoporosis in postmenopausal women ≥50 years of age, who otherwise have low risk for fracture, is warranted and should include the addition of calcium, vitamin D, and a bisphosphonate such as alendronate if corticosteroid treatment is expected to continue for at least 3 months at a dose of ≥7.5 mg/d.

Q: 2

Laboratory studies:

Albumin 4.0 g/dL (40 g/L)

Calcium 8.7 mg/dL (2.2 mmol/L)

Creatinine 0.7 mg/dL (61.9 µmol/L)

Phosphorus 2.9 mg/dL (0.94 mmol/L)

Parathyroid hormone 176 pg/mL (176 ng/L)

A 66-year-old woman comes to the office for management of osteoporosis discovered on a screening dual-energy x-ray absorptiometry (DEXA) scan. The patient has no personal history of fractures and no family history of parathyroid disease or low bone mineral density. She has hypertension treated with lisinopril but takes no other medications or supplements.On physical examination, vital signs are normal; BMI is 22. Dentition is good. Other than mild kyphosis, physical examination findings are unremarkable.The DEXA scan showed T-scores of −2.1 in the lumbar spine, −3.0 in the femoral neck, and −2.5 in the total hip. Radiographs of the lateral spine show no compression fractures.

Which of the following is the most appropriate next step in management?

A) Measurement of 1,25-dihydroxyvitamin D levelB) Measurement of 25-hydroxyvitamin D levelC) ParathyroidectomyD) Repeat DEXA scan in 1 year

Answer: B ; 25 1,25 at kidney; so 1,25 level may be normal

Question: 3• A 55-year-old man is reevaluated during a follow-up examination for a wrist

fracture and anemia. The patient is otherwise asymptomatic. He was treated in the emergency department 2 weeks ago after he slipped in his driveway and sustained a right wrist fracture; mild iron deficiency anemia was detected at that time. He had normal results of a routine screening colonoscopy 5 years ago. Since his emergency department evaluation, 3 stool samples have been negative for occult blood. He takes no medication.

• On physical examination, vital signs are normal; BMI is 19. Other than a cast on his right wrist, all other findings are normal.

• Hemoglobin level is 11.9 g/dL (119 g/L), and 25-hydroxyvitamin D level is 17 ng/mL (42 nmol/L). Results of a comprehensive metabolic profile and urinalysis are normal.

• A dual-energy x-ray absorptiometry (DEXA) scan shows T-scores of −1.6 in the lumbar spine, −2.2 in the femoral neck, and −1.9 in the total hip.

• Which of the following is the most appropriate next step in management?

A) Begin alendronateB) Begin teriparatideC) Repeat DEXA scan in 1 yearD) Screen for celiac disease

Answer: – D

Key Points

Prevention• Ensure that individuals of all ages receive an adequate

intake of calcium and vitamin D.• Ensure regular physical activity at all ages to optimize peak

bone mass and minimize subsequent bone loss, and counsel patients to avoid cigarette smoking.

Screening• Screen women aged 65 years or older with DEXA. Initiate

screening in younger patients and in men if they are at increased risk for osteoporosis or fracture.

Key Points

Diagnosis• Ask patients about diet, lifestyle, medications, family

history, falls, and prior fractures, and do a focused physical exam looking for evidence of secondary causes of osteoporosis.

• Perform DEXA in patients with suspected osteoporosis.

• Check calcium, phosphate, creatinine , CBC, thyroid and liver studies in most patients. Consider additional testing when clinically indicated.

Key PointsTherapy• Ensure oral calcium intake of 1200 mg/d and vitamin D intake of 800

IU/d.• Use bisphosphonates as first-line treatment, starting with

alendronate or risedronate.• Consider second-line agents in patients who cannot tolerate or do not

respond to bisphosphonates including raloxifene, teriparatide, and denosumab.

• Consider therapy with nasal calcitonin for women who have been postmenopausal for at least 5 years and for whom other agents have failed or in those with acute pain from osteoporotic fractures.

• Repeat DEXA 1 to 2 years after initiation of therapy to document response.

ACP Smart Medicine Approach

Screen women age 65 and older and men age75 and older with DEXA at least once,

Use FRAX to identify younger patients for screening. Repeat negative screens in 2 years if result will change management

• DXA Scan

DXA scan

Compression fracture of L2

Case Vignette

• A 62-year-old healthy woman presents for routine care.

• She has no history of fracture, but she is worried about osteoporosis because her mother had a hip fracture at 72 years of age.

• She exercises regularly and has taken over-the-counter calcium carbonate at a dose of 1000 mg three times a day since her menopause at 54 years of age.

• This regimen provides 1200 mg of elemental calcium per day.

• She eats a healthy diet with multiple servings of fruits and vegetables and consumes one 8-oz serving of low-fat yogurt and one glass of low-fat milk almost every day.

• She recently heard that calcium supplements could increase her risk of cardiovascular disease and wants your opinion about whether or not she should receive them.

• What would you advise?

Recommended Dietary Intake of Elemental Calcium for Healthy Persons.

Bauer DC. N Engl J Med 2013;369:1537-1543

Well-Absorbed Dietary Sources of Calcium.

Bauer DC. N Engl J Med 2013;369:1537-1543

Widely Available Calcium Supplements.

Bauer DC. N Engl J Med 2013;369:1537-1543

Recommendationsendations

• The healthy postmenopausal woman described in the vignette reports a current total daily intake of 2240 mg of elemental calcium: a dietary intake of about 1040 mg (approximately 300 mg from nondairy sources and 740 mg from dairy products) and supplements that provide 1200 mg of calcium.

• Since her calcium intake is substantially greater than the IOM recommendation of 1200 mg per day for postmenopausal women, I would recommend that she increase her dietary calcium intake by 200 mg per day and discontinue her calcium supplements.

• If increasing her dietary intake is not feasible, she can reduce her calcium carbonate supplementation to one 500-mg tablet each day.

• She should be informed that supplement use, but not increased dietary intake, modestly increases the risk of nephrolithiasis, and she should be advised about a potential increased risk of cardiovascular events, although the evidence of the latter is currently inconsistent and inconclusive.

• If she continues to supplement her dietary calcium intake, she should be advised to take calcium carbonate with meals to optimize absorption.

References

• ACP Smart Medicine• National Osteoporosis Foundation, guidelines

2014• American College of Rheumatology• Annals of Internal Medicine• New England Journal of Medicine