Use of bisphosphonates in multiple myeloma patients in Denmark, 2005-2015.

PURPOSE To describe use of bisphosphonates in newly diagnosed multiple myeloma patients in Denmark. METHODS Using data from the Danish National Multiple Myeloma Registry, we conducted a population-based cohort study. Among patients newly diagnosed with multiple myeloma from 2005 to 2015, we examined use of bisphosphonates at first- and at progression/second-line anti-myeloma treatment overall, by patient characteristics, and myeloma complications. RESULTS Of 2947 patients starting first-line anti-myeloma treatment, 2207 patients (74.9%) received bisphosphonates. During a median follow-up of 27.6 (quartiles, 10.6-52.5) months, disease progression post-first-line treatment was recorded in 1546 patients, of whom 1065 (68.9%) were treated with bisphosphonates. Altogether, 80.9% of patients with and 37.6% of patients without myeloma bone disease were treated with bisphosphonates at first line and 73.0% and 42.7%, respectively, at progression/second line. Moreover, the proportion of patients treated with bisphosphonates decreased with increasing severity of renal impairment at first and at progression/second-line treatment. CONCLUSION The proportion of patients treated with bisphosphonates as part of first- and second-line anti-myeloma treatment increased with presence of myeloma bone disease and decreased by presence and severity of renal impairment. Overall, 25% of newly diagnosed multiple myeloma patients had no record of bisphosphonate treatment, potentially indicating an unmet need.