Department of Radiology, University of Washington, Seattle.
JAMA Intern Med. 2013 Sep 9;173(16):1514-21. doi: 10.1001/jamainternmed.2013.8725.
The symptomatic benefits of spinal augmentation (vertebroplasty or kyphoplasty) for the treatment of osteoporotic vertebral compression fractures are controversial. Recent population-based studies using medical billing claims have reported significant reductions in mortality with spinal augmentation compared with conservative therapy, but in nonrandomized settings such as these, there is the potential for selection bias to influence results.
To compare major medical outcomes following treatment of osteoporotic vertebral fractures with spinal augmentation or conservative therapy. Additionally, we evaluate the role of selection bias using preprocedure outcomes and propensity score analysis.
DESIGN, SETTING, AND PARTICIPANTS: Retrospective cohort analysis of Medicare claims for the 2002-2006 period. We compared 30-day and 1-year outcomes in patients with newly diagnosed vertebral fractures treated with spinal augmentation (n = 10,541) or conservative therapy (control group, n = 115,851). Outcomes were compared using traditional multivariate analyses adjusted for patient demographics and comorbid conditions. We also used propensity score matching to select 9017 pairs from the initial groups to compare the same outcomes.
Spinal augmentation (vertebroplasty or kyphoplasty) or conservative therapy.
Mortality, major complications, and health care utilization.
Using traditional covariate adjustments, mortality was significantly lower in the augmented group than among controls (5.2% vs 6.7% at 1 year; hazard ratio, 0.83; 95% CI, 0.75-0.92). However, patients in the augmented group who had not yet undergone augmentation (preprocedure subgroup) had lower rates of medical complications 30 days post fracture than did controls (6.5% vs 9.5%; odds ratio, 0.66; 95% CI, 0.57-0.78), suggesting that the augmented group was less medically ill. After propensity score matching to better account for selection bias, 1-year mortality was not significantly different between the groups. Furthermore, 1-year major medical complications were also similar between the groups, and the augmented group had higher rates of health care utilization, including hospital and intensive care unit admissions and discharges to skilled nursing facilities.
After accounting for selection bias, spinal augmentation did not improve mortality or major medical outcomes and was associated with greater health care utilization than conservative therapy. Our results also highlight how analyses of claims-based data that do not adequately account for unrecognized confounding can arrive at misleading conclusions.
对于骨质疏松性椎体压缩性骨折的治疗，脊柱增强（椎体成形术或后凸成形术）的症状益处存在争议。最近使用医疗计费索赔的基于人群的研究报告称，与保守治疗相比，脊柱增强可显著降低死亡率，但在这些非随机环境中，选择偏差有可能影响结果。
比较骨质疏松性椎体骨折采用脊柱增强或保守治疗后的主要医疗结果。此外，我们还通过术前结果和倾向评分分析评估选择偏差的作用。
设计、地点和参与者：对 2002-2006 年期间医疗保险索赔进行回顾性队列分析。我们比较了 30 天和 1 年新诊断为椎体骨折的患者接受脊柱增强（n=10541）或保守治疗（对照组，n=115851）的结果。使用传统的多元分析方法，根据患者的人口统计学和合并症调整结果。我们还使用倾向评分匹配从初始组中选择 9017 对来比较相同的结果。
脊柱增强（椎体成形术或后凸成形术）或保守治疗。
死亡率、主要并发症和医疗保健利用率。
使用传统的协变量调整，增强组的死亡率明显低于对照组（1 年时为 5.2%比 6.7%；风险比，0.83；95%CI，0.75-0.92）。然而，尚未接受增强治疗的增强组患者（术前亚组）在骨折后 30 天的医疗并发症发生率低于对照组（6.5%比 9.5%；比值比，0.66；95%CI，0.57-0.78），这表明增强组的病情较轻。在更好地考虑选择偏差后进行倾向评分匹配后，两组之间的 1 年死亡率无显著差异。此外，两组之间 1 年主要医疗并发症也相似，增强组的医疗保健利用率更高，包括住院和重症监护病房入院以及出院至熟练护理设施。
在考虑选择偏差后，脊柱增强并未改善死亡率或主要医疗结果，并且与保守治疗相比，与更高的医疗保健利用率相关。我们的结果还强调了如何分析基于索赔的数据，如果不能充分考虑到未被认识到的混杂因素，可能会得出误导性的结论。
