Introduction: Recombinant human bone morphogenic protein-2 (rhBMP-2) has been studied extensively to identify its benefits, risks, outcomes, and costs relative to autograft (local bone or iliac crest bone graft (ICBG)). This study seeks to analyze the cost effectiveness of rhBMP-2 plus autograft versus without rhBMP-2 in lumbar fusions.

Methods: 33 patients receiving rhBMP-2 in addition to autograft and 42 patients receiving only autograft for one or two-level lumbar fusion were analyzed. 1-year postoperative health outcomes were assessed via Visual Analogue Scale (VAS), Pain Disability Questionnaire (PDQ), Patient Health Questionnaire (PHQ-9), and EuroQol-5 Dimensions (EQ-5D) questionnaires. Direct medical costs were estimated using Medicare payment amounts, health resource utilization was recorded from patient EMRs, and indirect costs were based on patient missed work days and income. Postoperative 1-year cost/utility ratios and the incremental cost effectiveness ratio (ICER) were calculated to assess for cost effectiveness using a threshold of $100,000/QALY gained.

Results: Compared with preoperative health states, the rhBMP-2 cohort had 1-year postoperative improvement in VAS (6.1 vs. 4.2; p=0.02) and EQ-5D (0.42 vs. 0.56; p=0.01) scores. The control cohort had 1-year postoperative improvement in VAS (6.1 vs. 4.1), PDQ (101.6 vs. 61.8), PHQ-9 (9.8 vs. 5.5), and EQ-5D (0.46 vs. 0.65) scores (p<0.01 for all). The 1-year cost-utility ratio (Total Cost/?QALY) for the control cohort was significantly lower ($143,251/QALY gained) than that of the rhBMP-2 cohort ($272,414/QALY gained) (p<0.01). At 1-year follow-up, the control group dominated the ICER compared to the rhBMP-2 group.

Conclusions: Statistically significant improvements in quality of life measures were seen 1 year postoperatively for both cohorts. Clinical improvements (greater than the MCID) were also seen in both cohorts. Assuming durable gains in QALY, by 2 years, fusion with autograft but without rhBMP-2 would be cost effective ($71,625/QALY gained) whereas fusion with both autograft and rhBMP-2 would not be cost effective ($136,207/QALY gained).

Patient Care: As healthcare costs continue to rise, it is imperative that healthcare outcomes remain in line with the costs spent in the healthcare system. In 2009, the United States spent 16% of its gross domestic product (GDP) on healthcare services – a cost high enough to achieve a rank of 2nd by the World Health Organization (WHO) among all countries in annual healthcare spending. Yet, the WHO ranks the U.S. 37th out of 191 countries relative to the quality of its healthcare system. An increasing focus on healthcare costs has spurred interest in analyzing long term economic analysis of surgical procedures through comparative effectiveness research. This has been true of many fields, including spine surgery. Cost-effectiveness analysis (CEA) is a component of comparative effectiveness research (CER) that estimates the value of a healthcare intervention by not only comparing treatments based on quality of life gained, but also on the financial burden of the different treatments to the patient. A cost-utility analysis (CUA) is a specific type of CEA whereby the benefit of the intervention is expressed as a utility measure numerically chosen by the patient. A CUA also provides data that can be used to compare one intervention in one specific field of medicine (e.g., spine surgery) to other disciplines of medicine (e.g., cardiology). Rising costs associated with spinal fusion procedures, as well an increasing number of patients undergoing fusion and varying results of effectiveness, warrant intensive cost-utility analyses in the spine field. Cost-utility and incremental cost effectiveness ratios derived from CUAs can be used to better allocate healthcare resources and reduce the economic burden to both the patient and the healthcare institution in the future. Our research seeks to focus on calculating these ratios for common surgical procedures in the spine field in order to aid the spine surgeon or neurosurgeon in determining the most cost effective option for his or her patient population.

Learning Objectives: By the conclusion of this session, participants should be able to 1) Understand how to measure the cost effectiveness of surgical procedures using cost-utility and incremental cost effectiveness ratios, and 2) Discuss why rhBMP-2 may not be the most cost effective option for patients.

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