A more active role for gynecologists in the prevention of postmenopausal osteoporosis

Gynecologists often are the only doctors that postmenopausal women see on a regular basis. This should give an optimal basis for screening for osteoporosis and for the initiation of proper treatment if such a condition has been detected. Unfortunately this may not be the case in routine gynecological practice; only half of the women needing bone density assessment and/or bone medication succeeded to get it during primary care gynecological consultation [1]. Patients themselves may not be aware of the risk of osteoporosis, although they judge a hip fracture as a very serious event and are scared about such a prospect. Instead, apparently healthy postmenopausal women may pay visits to their gynecologists e.g. for the exclusion of gynecological cancer. However, the risk of gynecological cancer amounts only to 3.8% (cervical 0.3%, endometrial 2.3% and ovarian cancer 1.2%) for women between 60 and 85 years of age. In contrast, the risk of future bone fracture in this population is 50%!

Although women may be aware of the importance of lifestyle and dietary factors in bone protection, it makes a big difference if also the gynecologist takes up these issues while seeing postmenopausal women. Regular weight-bearing activity (e.g. 30–60 minutes of walking at least three times a week) strengthens bone. Calcium intake should be of order of 1000–1200 mg/day. Some women ask if excessive calcium is dangerous to blood vessels. We can assure them that the body absorbs only that much calcium needed for bone health; extra calcium passes through the gastrointestinal tract without harming any organ. Vitamin D is needed for calcium (and phosphate) absorption, and that is why each postmenopausal woman should take 800 IU of vitamin D per day through the year. We might add that that besides protecting bone, vitamin D supplementation decreases the risk of colon (and breast?) cancer. Further, we should not forget to mention that smoking is deleterious to bone; and encourage stopping it! These issues, which appear rather simple to busy gynecologists and which therefore may become neglected, should be taken up in each consultation with a postmenopausal woman.

One of the most pertinent questions when meeting postmenopausal women is whose bone mineral density (BMD) should be measured. There are no strict rules on this, but established osteoporosis risk factors (e.g. family history, petite size, heavy smoking, insufficient intake of calcium and/or vitamin D, use of heparin, antiepileptics or thyroxine, history of amenorrhea or premature menopause) should lead to the assessment of BMD. Because the long-term use of hormone therapy (HT) reduces the risk of hip and vertebrae fractures by 30–60%[2],[3], a history of no use of HT should lead to BMD assessment. It is also established that BMD declines by 2.3–6.2% in the first year after stopping HT, and thus BMD in these women should be studied within 3–5 years after the cessation of HT [4]. Some bone societies have recommended that all women from the age of 65 years onwards, or from 60 years if risk factors are present, should be studied at least once for BMD but this decision needs individual clinical judgment. BMD should be assessed in weight-bearing hip and lumbar spine which are most prone to fractures.

Interpretation of BMD scans needs training but each gynecologist can learn it. We must demand good quality control for BMD readings and we can compare two BMD readings only if they are obtained with the same equipment. The impact of low bone density on fracture risk depends on the age of the patient; a femoral neck T-score < −2.5 is associated with hip fracture risk in the next decade in 2.8% if a woman is 50 years old but in 18.3% if she is 70 years old at the time of assessment [5].

The initiation of osteoporosis therapy is indicated if total hip or spine T-score is less than −2.5. The therapy is also indicated if T-score is between −2.0 and −2.5 and there is at least one additional risk factor. Moreover, therapy is always indicated, and even without BMD assessment, if a bone fracture has already occurred [6]. In clinical routine we should avoid the use of unnecessary treatments which just increase costs and which may also cause side-effects, and therefore each treatment decision should carefully considered.

We gynecologists should master all bone treatments. HT is often the most useful regimen for osteopenia and even for mild osteoporosis. The bone maintains its sensitivity towards estrogen up to the senium, and even very low doses (estradiol 0.25 mg orally or 14 μg transdermally) are bone-effective [7-9]. Bisphosphonates (aledronate, risedronate, ibandronate, tsoledronate) all reduce bone resorption, whereas strontium ranelate reduces resorption but may also enhance bone formation. Calcitonin is one option and is especially suitable if vertebral fractures have already occurred because it relieves pains. In our comparative trial on osteoporotic elderly women, HT was at least as effective as alendronate to raise BMD in hip and spine, and a combination of HT and alendronate was not more effective than either agent alone [10]. Thus, in regard to bone, there is no reason to combine HT and bisphosphonate.

To sum up, the large number of post-war ‘baby boomers’ are now slightly above 60 years of age. Due to negative reports in the lay press, the use of bone- protecting HT has been declining. Therefore, osteoporosis is–and will continue to be–a growing dilemma in the Western world. We gynecologists should take a more active role in the screening and treatment of osteoporosis, because we often are the only physicians whom postmenopausal women see on a regular basis.