Low doses of the medication lasofoxifene can reduce the risk of vertebral and non-vertebral fractures, ER-positive breast cancer, coronary heart disease and stroke in postmenopausal women with osteoporosis. That's the finding of a new study in the latest issue of the New England Journal of Medicine.
Lasofoxifene is a non-steroidal selective estrogen receptor modulator (SERM) that has been shown to decrease bone loss and bone weakening, and reduce cholesterol levels, all common problems in postmenopausal women. However, its impact on other health issues for this population was not well understood.
"This is the first SERM that reduces the risk of all of these conditions at once," says Steven Cummings, M.D., of the San Francisco Coordinating Center at the California Pacific Medical Center Research Institute, and the lead author of the study. "Not only did it reduce vertebral fractures, which was not unexpected, it also reduced the risk of non-vertebral fractures - injuries to the arms, legs, ribs, hips - that are the most common injuries to people with osteoporosis and the main causes of disability."
The researchers followed 8,556 women, ages 59 to 80, over the course of 5 years. Two thirds of the women were given a daily dose of lasofoxifene (either 0.25mg or 0.5mg) and the other third were given a placebo.
The women were given lateral spine radiographs at 12, 24, 36, and 60 months to measure bone density and identify possible fractures. The women also underwent annual mammograms and clinical breast exams to detect breast cancer.
At the end of the five years patients who took lasofoxifene experienced fewer vertebral fractures than the placebo group - a 58 percent reduction in the patients taking 0.5mg a day and 31 percent in the lower dose group - and non-vertebral fractures (24 percent and 10 percent respectively). Those taking lasofoxifene also experienced increases in bone density compared to the placebo group.
Patients taking lasofoxifene experienced a reduction in their risk of estrogen receptor (ER) positive breast cancer (81 percent and 48 percent respectively), and a reduction in LDL (the so-called bad) cholesterol of around 16 percent.
The researchers say the results were not all positive. Patients taking lasofoxifene were at higher risk of experiencing a venous thromboembolic event or blood clot.