Longitudinal assessment of bone mineral density changes after heart transplant: Implications for DXA screening frequency

Abstract

We evaluated the rate of bone mineral density (BMD) loss after heart transplant using dual-energy X-ray absorptiometry (DXA) to determine the optimal DXA surveillance frequency. This retrospective study involved 153 heart transplant recipients aged 50 years or greater, followed for up to 5,614 (median 1,111) days after transplant. Mixed-effects models with random intercepts were used to evaluate BMD changes over time. We found that males had higher BMD at each site before transplant (p < 0.05 for all). Patients with normal BMD pretransplant had a greater rate of BMD loss compared to patients who had low BMD pretransplant at the femoral neck. The rate of BMD loss was fastest at the femoral neck in patients with normal BMD pretransplant, with an estimated annual femoral neck BMD decrease of 0.00905 g/cm². The expected time for a patient to have a significant change in BMD is 1,332 days (95% confidence interval [909, 2,493] days).