Cost–Utility Analysis of rhBMP-2 Use in Adult Spinal Deformity Surgery

Abstract

Study Design. Economic modeling of data from a multicenter, prospective registry. Objective. The aim of this study was to analyze the cost utility of recombinant human bone morphogenetic protein-2 (BMP) in adult spinal deformity (ASD) surgery. Summary of Background Data. ASD surgery is expensive and presents risk of major complications. BMP is frequently used off-label to reduce the risk of pseudarthrosis. Methods. Of 522 ASD patients with fusion of five or more spinal levels, 367 (70%) had at least 2-year follow-up. Total direct cost was calculated by adding direct costs of the index surgery and any subsequent reoperations or readmissions. Cumulative quality-adjusted life years (QALYs) gained were calculated from the change in preoperative to final follow-up SF-6D health utility score. A decision-analysis model comparing BMP versus no-BMP was developed with pseudarthrosis as the primary outcome. Costs and benefits were discounted at 3%. Probabilistic sensitivity analysis was performed using mixed first-order and second-order Monte Carlo simulations. One-way sensitivity analyses were performed by varying cost, probability, and QALY estimates (Alpha = 0.05). Results. BMP was used in the index surgery for 267 patients (73%). The mean (±standard deviation) direct cost of BMP for the index surgery was $14,000 ± $6400. Forty patients (11%) underwent revision surgery for symptomatic pseudarthrosis (BMP group, 8.6%; no-BMP group, 17%; P = 0.022). The mean 2-year direct cost was significantly higher for patients with pseudarthrosis ($138,000 ± $17,000) than for patients without pseudarthrosis ($61,000 ± $25,000) (P < 0.001). Simulation analysis revealed that BMP was associated with positive incremental utility in 67% of patients and considered favorable at a willingness-to-pay threshold of $150,000/QALY in >52% of patients. Conclusion. BMP use was associated with reduction in revisions for symptomatic pseudarthrosis in ASD surgery. Cost–utility analysis suggests that BMP use may be favored in ASD surgery; however, this determination requires further research. Level of Evidence: 2

A Large Database Study of Hospitalization Charges and Follow-up Re-admissions in Us Lumbar Fusion Surgeries Using a Cellular Bone Allograft (CBA) Versus Recombinant Human Bone Morphogenetic Protein-2 (rhBMP-2)

“…However, these rates were signi cantly lower in the V-CBA group among patients receiving single-level treatments only (Table 3), in spite of the fact that the VCBA group had statistically higher rates of initial comorbidities with the potential to negatively impact clinical outcomes. The low rate of subsequent lumbar fusion with rhBMP-2 is a frequentlycited bene t over ICBG and a principal justi cation of its cost [11,13,27]. As such, the performance of VCBA in this study is notable, especially in light of the substantially lower average initial hospitalization charges observed for V-CBA patients, and in spite of the higher level of initial comorbidities in this group.…”

“…In spite of serious complications attributed to rhBMP2 in the spine (eg, wound complications, retrograde ejaculation in males, and heterotopic ossi cation) [9,10], several clinical studies have demonstrated that rhBMP-2 in lumbar fusion surgeries increases fusion rates compared to ICBG, while also decreasing fusion time and refusion rates [11]. However, rhBMP-2 remains relatively expensive [12,13] and some thirdparty payers have become increasingly unwilling to reimburse for its prevalent off-label use, leading to downward trends in its overall use from all-time highs in 2009 [7,14].…”

“…is almost universally reported to increase hospitalization costs[6,12,13,[25][26][27], the question remains as to why such large disparities should exist, as they cannot be explained by direct product costs alone. A de nitive answer to this question is beyond the scope of this study and its data; however, an exploration…”

A Large Database Study of Hospitalization Charges and Follow-up Re-admissions in US Lumbar Fusion Surgeries Using a Cellular Bone Allograft (CBA) versus Recombinant Human Bone Morphogenetic Protein-2 (rhBMP-2)

“…Although the use of rhBMP-2 is almost universally reported to increase hospitalization costs [6,12,13,[25][26][27], the cause of these large disparities is unknown, as they cannot be explained by direct product costs alone. A de nitive answer to this question is beyond the scope of this study; however, an exploration of potential causes is warranted, albeit speculative.…”

“…In spite of serious complications attributed to rhBMP-2 in the spine (eg, wound complications, increased myelopathy/radiculopathy, and heterotopic ossi cation) [9,10], several clinical studies have demonstrated that rhBMP-2 in lumbar fusion surgeries increases fusion rates compared to ICBG, while also decreasing fusion time and refusion rates [11]. However, rhBMP-2 remains relatively expensive [12,13] and some third-party payers have become increasingly unwilling to reimburse for its prevalent off-label use, leading to downward trends in its overall use from all-time highs in 2009 [7,14].…”