Add a bisphosphonate to raloxifene?
A healthy, asymptomatic woman with a stable bone mineral density of -2.5 on dual energy x-ray absorptiometry (DEXA) has been taking raloxifene (Evista) for seven years along with calcium and vitamin D. She also exercises regularly. Should bisphophonates be added to the Evista? Or should the Evista be stopped and the bisphosphonates used alone for osteoporotic fracture prevention? I have read that there is a synergistic bone building effect when the two drugs are used.
—Steve Olson, MD, MPH, Colebrook, N.H.
Since DEXA scanning shows seven years of stability in this patient, it is likely that the antiresorptive effect of raloxifene is sufficient to prevent the expected decline in density that we all undergo over time. You can verify this beneficial effect by the occasional testing of urinary N-telopeptide, a biomarker that should show a level close to the premenopausal norm. It is not likely that you will build bone by combining two antiresorptives after this duration of therapy, but teriparatide (Forteo) could provide such an effect over 18-24 months if the patient desires greater bone density to reduce future fracture risk.
—Jack Waxman, MD (117-6)