BACKGROUND Approximately 2,700 lung transplants are performed annually in the United States. These patients are at increased risk of developing low bone mineral density (BMD) (osteopenia/osteoporosis) and subsequent fractures. Dual-energy X-ray absorptiometry (DXA) is the most common method used for screening for low BMD; however, the optimal surveillance frequency for low BMD using DXA is unknown. METHODS We evaluated the change in femoral neck, total femur, L1, L2, L3, and L4 BMD after lung transplant in a retrospective cohort of 259 patients (69.9% male) who were followed with serial DXA scans for a median of 725 (interquartile range [361-1,116]) days after transplant. Generalized linear mixed-effects models adjusting for sex, time, time-squared, baseline osteopenia/osteoporosis, active rejection, and their interaction terms were used to model the rate of change of BMD at each site. The final multivariable models for the femoral neck, L1, and L4 BMD measurements had random slopes and intercepts, and the models for the total hip, L2, and L3 measurements had random slopes. RESULTS Sixty-five percent of the patients undergoing lung transplants had osteopenia or osteoporosis before transplant. Men exhibited higher baseline BMD levels compared to women at all sites (p < 0.001 for all). After the transplant, the greatest rate of BMD decrease was at the femoral neck. Although patients with low BMD had significantly lower baseline BMDs (p < 0.001 for all), they experienced a slower rate of BMD decrease at all sites compared to patients with normal BMD at baseline (p < 0.001 for all). All patients received corticosteroids. Patients with low BMD at baseline had significantly higher odds of receiving bisphosphonate therapy (odds ratio = 3.95, 95% confidence interval [CI] [1.44, 13.51], p = 0.003). We estimated that a significant change in the femoral neck BMD would be expected to occur within 409 days (95% CI [131, 708]) and again at 867 days (95% CI [551, 1,216]) after lung transplant. CONCLUSIONS Patients undergoing lung transplant should be screened annually with DXA for the first 2 years after transplant, consistent with the current International Society for Heart and Lung Transplantation guidelines.

中文翻译：

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使用双能 X 射线吸收测定法 （DXA） 对肺移植后患者进行低骨密度 （BMD） 筛查的优化监测频率。


背景 美国每年大约进行 2,700 例肺移植手术。这些患者发生低骨密度 （BMD） （骨质减少/骨质疏松症） 和随后骨折的风险增加。双能 X 射线吸收测定法 （DXA） 是用于筛查低 BMD 的最常用方法;然而，使用 DXA 对低 BMD 的最佳监测频率尚不清楚。方法 我们评估了肺移植后股骨颈、股骨总、L1、L2、L3 和 L4 BMD 的变化，回顾性队列纳入了 259 例患者 （69.9% 为男性），这些患者在移植后进行了连续 DXA 扫描，中位数为 725 天 （四分位距 [361-1,116]） 天。使用调整性别、时间、时间平方、基线骨质减少/骨质疏松症、主动排斥反应及其交互项的广义线性混合效应模型来模拟每个部位 BMD 的变化率。股骨颈、L1 和 L4 BMD 测量的最终多变量模型具有随机斜率和截距，而全髋、L2 和 L3 测量的模型具有随机斜率。结果 65% 的肺移植患者在移植前患有骨质减少或骨质疏松症。与女性相比，男性在所有部位都表现出更高的基线 BMD 水平 （p < 0.001）。移植后，骨密度下降率最高的是股骨颈。尽管低 BMD 患者的基线 BMD 显着较低 （p < 0.001），但与基线时 BMD 正常的患者相比，他们在所有部位的 BMD 下降速度较慢 （p < 0.001）。所有患者均接受皮质类固醇治疗。基线时 BMD 低的患者接受双膦酸盐治疗的几率显著更高 （比值比 = 3。95,95% 置信区间 [CI] [1.44， 13.51]，p = 0.003）。我们估计，股骨颈 BMD 预计将在肺移植后 409 天 （95% CI [131， 708]） 和 867 天 （95% CI [551， 1,216]） 再次发生显着变化。结论 接受肺移植的患者在移植后的前 2 年应每年进行 DXA 筛查，这与当前的国际心肺移植学会指南一致。