Osteopenia: When Does Decreased Bone Density Become a Disease Requiring Treatment?

Osteoporosis is routinely treated with bisphosphonates to prevent fractures. A new study suggests that osteopenia should be treated too. But questions remain.  Bisphosphonate drugs have been shown to increase bone density and prevent fractures in postmenopausal women with osteoporosis (remember Sally Field in those ads for Boniva?) but what about women with milder decreases in