Preventing bone loss in women

An injection of a drug called ibandronate given every three months seems to be an effective new treatment for preventing bone loss in postmenopausal women. Ibandronate, also known by the brand-name Bondronat, belongs to a class of bone-boosting drugs called bisphosphonates. The four-times-a-year treatment may offer an effective and convenient alternative to oestrogen replacement therapy for preventing the bone-thinning condition of osteoporosis. In osteoporosis, bones become thin, weak and are more likely to break. This happens because after menopause the oestrogen that helps reduce bone absorption is no longer available.Researchers from Haugesund, Norway, conducted a clinical trial of three doses of ibandronate in preventing postmenopausal osteoporosis. The study included 629 postmenopausal women, categorised according to time since menopause and their lumbar spine bone mineral density (BMD) at the time of entry into the trial. The women were randomly assigned to receive 0.5, 1, or 2 milligrams of ibandronate - or an inactive placebo - by injection every 3 months. All of the women were also given daily calcium supplements.After 1 year, ibandronate produced increases in average spine BMD of 1.0 percent, 1.8 percent, and 2.5 percent among those given 0.5 mg, 1 mg, and 2 mg respectively. In contrast, women given placebo injections had a 0.4 percent loss of BMD. Significantly greater gains in BMD in the hip were also seen with all three doses of ibandronate compared with placebo. Women who already had thinning bones and who were given 2 mg of ibandronate had the highest gain in bone density. While the drug has already been shown to prevent fractures in postmenopausal women, the researchers said that this is the first study demonstrating the efficacy and tolerability of intermittent intravenous injections of a bisphosphonate in preventing bone loss in early postmenopausal women.