Update: A 55-Year-Old Woman With Osteopenia

In a December 2006 Clinical Crossroads article,¹ Steven R. Cummings, MD, discussed a 55-year-old woman with low bone mineral density (BMD). Ms Q had her first BMD study in 2000, when her T score was −1.4 at the spine and −0.6 at the total hip. Having taken postmenopausal hormone therapy for breast cancer risk reduction since 1999, as was the practice until trials demonstrated that it had the opposite effect,² she continued taking daily estrogen and medroxyprogesterone acetate. In 2001, Ms Q began to experience trouble with her balance. A neurological examination revealed that she had had several tiny strokes. An evaluation revealed a small atrial septal defect and a weakly positive test for antiphospholipid antibody. As a result, Ms Q discontinued hormone therapy, was prescribed dose-adjusted warfarin, and began physical therapy; her next neurological examination result was normal. Ms Q had BMD testing in 2003 and again in 2005. Between tests, her total hip T score declined from −0.7 to −1.0 and her anterior-posterior spine (L1-L4) declined from −1.9 to −2.3. Ms Q is an avid golfer (when weather permits) and takes 1500 mg of calcium and a multivitamin daily.

Dr Cummings emphasized the importance of continued exercise for Ms Q. He encouraged her to continue playing golf, particularly without the aid of a cart. Though he was unsure of the benefits of calcium and vitamin D supplements, he saw no significant risks from her continuing them. Recognizing her decreased T score between BMD tests in 2000 and 2005, Dr Cummings believed this could be attributed to her discontinuation of estrogen therapy. He recommended that Ms Q have her BMD tested in the next 1 or 2 years to determine if it was rapidly declining; if so, he recommended that she begin investigating pharmacological options. Dr Cummings explained that estrogen was the only drug proven to reduce the risk of fracture in women like Ms Q, but given her history of stroke, Ms Q would not be a good candidate. As a result, he advised her against beginning any pharmacological therapy at the time but suggested she reassess her BMD in the near future.

In 2007, Ms Q again underwent BMD testing. Her results showed that her BMD has not significantly changed since her 2005 test.

I remember being happy with the results of my most recent BMD test because I didn't get worse. What a relief to hear that!

Since the article was written, I haven't broken any bones and I’ve continued to take calcium and vitamin D. I’ve also been pretty good about strength training. I’m doing some light weight exercise for my upper body and about 3 to 4 times per week, I do an exercise where I stand up on my toes. I’ve also been very good about practicing my balance—I stand on one leg in order to put pressure on the other leg.

I have not been very good about setting up a walking or running regimen. I do walk about 30 minutes per day during my commute to work, but I don't have a consistent workout for 30 minutes, 4 times per week. I do play golf, and I have been walking, but as soon as it gets hot out, I’ll probably use the cart. I know I’ve got to get better at this, but life has just been too busy! I’m certainly not giving myself high marks right now.

I’m trying to change my mind-set about exercise. I’m trying to use walking to “deal with stress” instead of walking to “deal with exercise.” I’m hoping that by changing my purpose, I might get myself out there more, but sometimes it just feel like one more thing I have to schedule.

My mother is 93 years old and has severe arthritis and osteoporosis in her back. Recognizing this just reinforces what I need to do in order to keep myself in the best shape possible. It's hard to dismiss a concern like this when your future is just staring you in the face.

Since Ms Q's case was discussed, a computer algorithm, FRAX, has been developed to estimate the risk of fracture; it is available on the Web at http://www.shef.ac.uk/FRAX/. It estimates 10-year risk of hip or major osteoporotic fracture (hip, wrist, humerus, and clinical vertebral fracture) based on several risk factors and femoral neck BMD. In retrospect, Ms Q's age (55 years), femoral neck bone density (T score = −1.9), and absence of the specified risk factors indicated a 1.2% risk of hip fracture and 7.8% risk of major osteoporotic fracture over 10 years. The National Osteoporosis Foundation has subsequently issued guidelines that include a recommendation to consider pharmacologic therapy if the 10-year risk of hip fracture exceeds 3% or the risk of major osteoporotic fracture exceeds 20% (http://www.nof.org/professionals/Clinicians_Guide.htm). These estimates should provide Ms Q and her physician further reassurance that she does not need pharmacologic therapy and that the best course remains the regular exercise that she is trying to maintain.

Recent meta-analyses have confirmed the value of vitamin D supplementation, at least 800 IU/d, for prevention of fractures in elderly women, particularly those living in institutions, but there is still no evidence that supplementation will reduce fracture risk for healthy middle-aged women such as Ms Q.^{3 - 5} Observational studies suggest that increasing 25-hydroxyvitamin D levels might reduce risk of cardiovascular disease, which may be of particular value to Ms Q.⁶ However, this possibility needs testing in randomized trials.

Ms Q's BMD appears to have stabilized, as expected, as time has passed since stopping estrogen therapy. She may wish to repeat the measurement in 2 years.