Ob/Gyns are well trained to care for more than 99% of women with osteopenia and osteoporosis. Yet most women at risk are not being diagnosed or treated. Since recent publication of randomized clinical trials, however, we have clearer direction on the decisive diagnosis and management questions.
Who should have a bone mass test?
Ob/Gyns know best
Ob/Gyns were significantly more likely to order bone densitometry than internists and family physicians. However, any physician, including Ob/Gyns, who believed (mistakenly) that calcium-plus-vitamin D effectively treats osteoporosis or that osteoporosis should not be diagnosed by densitometry used screening less frequently than physicians without those beliefs.
Any woman should have bone density testing if it might influence her medical care. Osteoporosis is notoriously difficult to diagnose without densitometry.1
Besides identifying women at risk of fracture due to osteopenia or osteoporosis who are good candidates for drug therapy, testing can help motivate women to stop smoking, exercise, and take calcium and vitamin D to prevent bone loss. Just as women should know their weight, serum cholesterol, blood pressure, and mammographic findings, hypoestrogenic women should know their T-score.
The issue of relative costs and benefits of bone density testing is complex and continues to evolve. Although national organizations have guidelines (TABLE 1), it is not clear if their sensitivity and specificity are optimal for identifying appropriate candidates for screening.
A reliable, quick tool identifies who to test
Cadarette SM, Jaglal SB, Murray TM, McIsaac WJ, Lawrence L, Brown JP. Evaluation of decision rules for referring women for bone density by dual-energy X-ray absorptiometry. JAMA. 2001;286:57–63.
A 3-item Osteoporosis Risk Assessment Instrument was more sensitive and specific in identifying screening candidates than the National Osteoporosis Foundation (NOF) criteria, according to an analysis of screening algorithms used in 2,365 menopausal women in the Canadian Multicentre Osteoporosis Study. A simple calculation based on age, weight, and estrogen use (TABLE 2) was clinically applicable.
In my practice, I focus on all women who have been hypoestrogenic for 12 to 24 months regardless of age, women with a previous low-trauma fracture, and women who weigh less than 132 pounds. Evidence is mounting that early treatment of bone loss is the best way to prevent future fracture. Well before osteoporosis is detected, significant structural integrity of the spine and hip has been lost.
It is my belief that guidelines will ultimately recommend bone mineral testing for all hypoestrogenic and menopausal women. This practice will help start pharmacologic therapy early in the disease, maximally protecting bone and reducing fracture risk. A large-scale randomized prospective trial of bone mineral density testing with long-term follow-up will be needed to crystallize this recommendation.
- Make use of prevention drugs
- Test any woman over 50 who has any fracture
Criteria, risk factors for densitometry
|The National Osteoporosis Foundation, the North American Menopause Society, the American College of Obstetricians and Gynecologists, and the American Association of Clinical Endocrinologists concur on these criteria and risk factors for bone mineral density testing:|
|CRITERIA FOR SCREENING|
|Age 65 years or older|
|Age less than 65 years with risk factors (see below)|
|If densitometry results will influence use of drug treatment|
|Diseases and treatments associated with osteoporosis (eg, rheumatoid diseases, chronic glucocorticoid therapy)|
|Diseases associated with osteoporosis|
|Body weight less than 127 pounds|
|Low-trauma fracture in a first-degree relative|
|Use of chronic glucocorticoid therapy|
Rapid risk assessment: Test bone density if score is 9 or more
|The Osteoporosis Risk Assessment Instrument advises testing all women age 65 or older, and menopausal women starting at age 55 who weigh less than 154 pounds and are not taking estrogen.|
|Older than 74||15|
|Less than 60 kg (132 pounds)||9|
|60 to 70 kg (132 to 154 pounds)||3|
|Not currently using estrogen||2|
|Source: Cadarette SM, Jaglal SB, Kreiger N, McIsaac WJ, Darlington GA, Tu JV. Development and validation of the Osteoporosis Risk Assessment Instrument to facilitate selection of women for bone densitometry. CMAJ. 2000;162:1289–1294.|
When should treatment start?
Fracture begets fracture, treatment reduces risk
Delmas PD, Genant HK, Crans GG, Stock JL, Wong M, Siris E, Adachi JD. Severity of prevalent vertebral fractures and the risk of subsequent vertebral and nonvertebral fractures: results from the MORE trial. Bone. 2003;33:522–532.