Evaluation of bone mineral density and fat-lean distribution in patients with multiple myeloma in sustained remission

To study the usefulness of bone mineral density (BMD) in the follow-up of myeloma (MM) patients, BMD was evaluated in 44 MM patients in sustained remission for at least 2 years (35.4 +/- 10.5 months) after high-dose or conventional chemotherapy in a retrospective study. Patients never received bisphosphonates before or during the follow-up. Patients underwent lumbar spine (LS) BMD and a whole body (WB) BMD testing before therapy and at least once in the remission period. At baseline, mean LS BMD was 0.863 +/- 0.026 g/cm2, mean lumbar Z-score was -1.45 SD. LS BMD significantly increased from baseline by 5 +/- 1.8%, 9.3 +/- 1.7%, and 14 +/- 1.9% at 1, 2, and 3 years, respectively. The percentage of patients with a T-score below 2.5 SD decreased from 39% at baseline to 18.5% at 3 years. Compared with baseline, WB BMD decreased by -2.8 +/- 0.5%, -2.6 +/- 0.7%, and -1.7 +/- 0.6% at 1, 2, and 3 years, respectively. Mean percentage change of the fat compartment increased from baseline by +28.4 +/- 7.1% at the trunk, and +17.1 +/- 5% in peripheral areas at 3 years. In conclusion, in MM patients in remission after chemotherapy, LS BMD progressively increased after a mean follow-up of 3 years. These patients never received bisphosphonates, so this increase was related to the anti-myeloma treatment. The major effect on BMD was observed at the LS, which is primarily composed of trabecular bone containing the bone marrow. Interestingly, a drastic increase of the fat content was also observed. These results underlined that BMD and fat-lean evaluation could be of interest in the follow-up of MM patients.