Bone health counseling begins in adolescence, new guidance states
Talk to women of all ages about bone health, says new ACOG guidance
Your practice includes adolescent patients, young women of reproductive age, those in perimenopause, and newly menopausal women. Which group should receive counseling about bone health?
All of them, according to a new practice bulletin from the American College of Obstetricians and Gynecologists (ACOG).1 The new guidance calls for clinicians to address bone health with all patients, beginning at puberty and adolescence when girls are at their peak bone-building stage.
A skeletal disorder characterized by loss of bone mass, deterioration of microarchitecture, and a decline in bone quality, osteoporosis leads to increased vulnerability to fracture. The condition is five times more prevalent among women than among men, and women have twice the fracture rate of men, according to current statistics.1 Risk of fracture comes at a high price; in 2005, the cost for direct care of the estimated 2 million osteoporosis-related fractures in the United States was projected at $17 billion, with hip fractures accounting for about 72% of the cost.2
Adolescence is a critically important window for bone development, as more than half of an individual's peak bone mass is accrued during adolescence, says Catherine Gordon, MD, MSc, director of the Division of Adolescent Medicine at Hasbro Children's Hospital and professor of pediatrics at the Warren Alpert Medical School of Brown University, both in Providence, RI.
Puberty and early adolescence is prime time for bone building. The acquisition of bone that occurs during childhood and adolescence constitutes 90% of adult bone mass. Most bone growth and bone mineral content is gained in the 2-4 years before and after peak height velocity; the mean age of peak height velocity in females is estimated at 11.8 (plus or minus 1.0) years.3
"I was pleased to see that the recent ACOG bulletin on osteoporosis included adolescents and young women as patients in whom bone health should be considered," says Gordon. "The report thoroughly reviews groups of patients who may be 'at risk' for bone loss, as well as the importance of proper nutrition — with adequate calcium and vitamin D — weight-bearing exercise, and avoidance of lifestyle issues, such as smoking and excessive alcohol, that are deleterious to bone."
The Institute of Medicine recommends 1,300 IU (international units) of daily calcium for girls ages 9-18; 1,000 IU per day for women ages 19–50; and 1,200 IU per day for women over age 50.4 The institute also has increased the recommended dietary allowance of vitamin D from 200 to 400 IU to 600 IU per day for most people, and from 600 IU to 800 IU per day after age 70.4
The 2010 Dietary Guidelines for Americans call for everyone 9 years old and older to consume three cups of low-fat dairy foods as part of a healthful diet.5 However, teen girls fall short of the mark; it is estimated adolescent females consume about 1.7 servings a day.6
Use patient handouts to educate teens on the importance of proper intake. The "Milk Matters" campaign developed by the National Institute of Child Health and Human Development offers several free publications and materials about the importance of calcium for children and teens. (Visit the web page to download material at http://1.usa.gov/ScWISx.)
It is important to recognize that it's more difficult to establish a diagnosis of osteoporosis in an adolescent or young adult, as World Health Organization criteria for osteoporosis exist only for postmenopausal women, Gordon says. A bone mineral density (BMD) Z-score, which compares the patient's BMD to the mean BMD of women her age, is the key data point to consider in younger patients, says Gordon. Osteoporosis cannot be defined based on a densitometry result alone, Gordon notes. Evidence of skeletal fragility, such as a low trauma fracture, must be established as well in an adolescent, she observes.
How about contraception?
What role does contraception play in bone health? According to Contraceptive Technology, combined oral contraceptives (COCs) have a favorable impact on bone for high-risk women.7 Women who have hypothalamic amenorrhea have low levels of circulating estrogens; research indicates COC use increases BMD.8
The use of depot medroxyprogesterone acetate (DMPA) for contraception suppresses ovarian production of estradiol, an inhibitor of bone resorption.9 This finding has led to concern that DMPA use might put women at risk for osteoporosis. The Food and Drug Administration added a "black box" warning in 2004 to the contraceptive injection depot medroxyprogesterone acetate (DMPA, Depo-Provera, Pfizer, New York City; Medroxyprogesterone Acetate Injectable Suspension USP, Teva Pharmaceuticals USA, North Wales, PA) advising that prolonged use might result in BMD loss. However, a 2008 ACOG committee opinion stated that concerns about the effects of DMPA on bone mineral density shouldn't prevent clinicians from prescribing the method, nor should its use be limited to two years.10 The US Medical Eligibility Criteria for Contraceptive Use ranks use of DMPA as Category 1 (no restriction on use) in women 18 to 45 years of age and Category 2 (advantages of the method generally outweigh theoretical or proven risks) in younger women.11
Midlife signals changes
When might bone mineral content start to wane? Look to midlife, when the bone turnover process shifts to greater resorption than formation in women and men. The rate of bone loss as years advance is controlled by such factors as genetic predisposition and endogenous estrogen levels. The time of most rapid bone loss in women occurs with the decline in estrogen levels associated with menopause; science defines this period of rapid bone loss beginning one year before the final menses and lasting about three years. During this time, there is an estimated 6% and 7% bone loss at the femoral neck and lumbar spine, respectively.12
Clinicians look to dual-energy X-ray absorptiometry (DXA) of the lumbar spine and hip as the gold standard for diagnosing osteoporosis, with BMD screening beginning at age 65 for all women. Postmenopausal women younger than 65 should be screened only with DXA if they have significant risk factors for osteoporosis and/or bone fracture, the ACOG guidance states.1 (See box, below, for when to use dual-energy X-ray absorptiometry screen before age 65.)
When to screen BMD in women under 65 Screen bone mineral density (BMD) in postmenopausal women younger than age 65 if any of the following are noted:
From: American College of Obstetricians and Gynecologists. Osteoporosis. Practice Bulletin. Obstet Gynecol 2012; 120(3):718-734. |
As an addition to screening, FRAX, a fracture risk assessment tool developed by the World Health Organization, can help to further predict a person's risk of bone fracture in the next 10 years. It can be used to determine if a patient is at high risk for fracture if her initial scan indicates low bone mass. The assessment tool is based on such risk factors as age, body mass index, history of fracture, daily alcohol intake, and whether a patient smokes, has rheumatoid arthritis, or has any other secondary causes of osteoporosis. (To learn more about the tool, visit its web site, http://bit.ly/bXtKw5.)
Anita Nelson, MD, professor in the Obstetrics and Gynecology Department at the David Geffen School Of Medicine at the University of California in Los Angeles, says, "I think is important that those who care for women be aware of the fracture risk assessment tool model to identify those women with osteopenia — but not osteoporosis — who need treatment to prevent fractures. Remember, there is a version of FRAX that can use the women's body mass index as a proxy if she has not had a DXA scan."
According to the ACOG guidance, in the absence of new risk factors, dual-energy X-ray absorptiometry screening should not be performed more frequently than every two years.1 The fracture risk assessment tool assessment should be used on an annual basis to monitor the effect of age on fracture risk, it advises.
Counsel on prevention
What can you do to help patients prevent poor bone health? Counsel women with osteoporosis or who are at risk about lifestyle changes to reduce the risk of bone loss and osteoporotic factors. Advise about the importance of performing weight-bearing exercises and muscle-strengthening exercises to reduce the risk of fractures and falls, taking the appropriate amount of vitamin D and calcium, stopping smoking and avoiding secondhand smoke, reducing alcohol intake, and adopting fall-prevention strategies. (Visit the National Institutes of Health Osteoporosis and Related Bone Diseases National Resource Center, http://1.usa.gov/98TKLI for patient resources. Under "Popular Publications," select "Bone Health and Osteoporosis: What It Means to You," then under "Publication Available In," select "PDF." The booklet also is available in Spanish and Chinese.)
References
- American College of Obstetricians and Gynecologists. Osteoporosis. Practice Bulletin. Obstet Gynecol 2012; 120(3):718-734.
- Burge R, Dawson-Hughes B, Solomon DH, et al. Incidence and economic burden of osteoporosis-related fractures in the United States, 2005–2025. J Bone Miner Res 2007; 22:465-475.
- Baxter-Jones AD, Faulkner RA, Forwood MR, et al. Bone mineral accrual from 8 to 30 years of age: an estimation of peak bone mass. J Bone Miner Res2011; 26:1,729-1,739.
- Institute of Medicine. Dietary Reference Intakes for Calcium and Vitamin D. Accessed at http://bit.ly/hK2KJS.
- U.S. Department of Agriculture, U.S. Department of Health and Human Services. Dietary Guidelines for Americans, 2010. Seventh ed. Washington, DC: U.S. Government Printing Office; 2010.
- Cook AJ, Friday JE. Pyramid Servings Intakes in the U.S. 1999-2002. Accessed at http://1.usa.gov/QLgLNd.
- Nelson AL, Cwiak C. Combined oral contraceptives (COCs). In: Hatcher RA, Trussell J, Nelson AL, et al. Contraceptive Technology: 20th revised edition. New York: Ardent Media; 2011.
- Hergenroeder AC, Smith EO, Shypailo R, et al. Bone mineral changes in young women with hypothalamic amenorrhea treated with oral contraceptives, medroxyprogesterone, or placebo over 12 months. Am J Obstet Gynecol 1997; 176(5):1,017-1,025.
- Bartz D, Goldberg AB. Injectable contraceptives. In: Hatcher RA, Trussell J, Nelson AL, et al. Contraceptive Technology: 20th revised edition. New York: Ardent Media; 2011.
- ACOG Committee Opinion No. 415: Depot medroxyprogesterone acetate and bone effects. Obstet Gynecol 2008;112:727-730.
- Centers for Disease Control and Prevention. US Medical Eligibility Criteria For Contraceptive Use, 2010. MMWR Recomm Rep 2010; 59 (RR04);1-6.
- Greendale GA, Young JT, Huang MH, et al. Hip axis length in mid-life Japanese and Caucasian U.S. residents: no evidence for an ethnic difference. Osteoporos Int 2003; 14:320-325.
You have reached your article limit for the month. Subscribe now to access this article plus other member-only content.
- Award-winning Medical Content
- Latest Advances & Development in Medicine
- Unbiased Content