Low bone density and fractures before and after pediatric lung transplantation

Abstract

Introduction: Children undergoing lung transplant are at risk for low bone mineral density (BMD) and fractures. The effect of lung transplantation on bone health in pediatric patients is unknown.

Materials and methods: We performed a retrospective chart review of all patients ages 2-21 years who underwent lung transplantation at our hospital from January 2000 to January 2015.

Results: 51 patients were studied. At the time of transplant evaluation, BMD Z-score was -2.2 ± 1.4, and 59% of patients had low BMD. BMD Z-score declined in the first year after treatment and returned to near-baseline by the third post-transplant year. Fractures occurred in 9 patients (18%) before and 15 patients (29%) after transplant. Bisphosphonate use was associated with improvement in BMD Z-score and lower mortality risk.

Conclusions: Pediatric patients had a high prevalence of low BMD at the time of lung transplant evaluation. BMD Z-scores declined in the year after transplant and returned to the pre-transplant level by the third post-transplant year while remaining below normal levels. Fractures were common at sites associated with significant morbidity. These findings support efforts to optimize bone health before and after pediatric lung transplantation, and future studies are needed to evaluate the role of bisphosphonates in these patients.

Keywords: Bisphosphonate; Bone mineral density; Fracture; Lung transplantation; Pediatric.

Figure 1

Changes in absolute BMD at the spine and hip after lung transplantation.

Figure 2

Changes in BMD Z-score at the spine and hip after lung transplantation. Unadjusted results are presented in panel 2a. Multivariable adjusted results after adjustment for 25(OH)D, height Z-score, and number of rejection episodes are presented in panel 2b.