Epidemiological trends in the utilization of bone morphogenetic protein in spinal fusions from 2002 to 2011.

STUDY DESIGN: Retrospective database analysis.

OBJECTIVE: A nationwide population-based database was analyzed to assess the utilization trends of bone morphogenetic protein (BMP) in spine fusion surgery from 2002-2011.

SUMMARY OF BACKGROUND DATA: The utilization of off-label BMP in spine procedures is not well characterized. The purpose of this study was to analyze a population-based database to characterize the national trends of BMP utilization in terms of incidence, demographics, costs, and mortality.

METHODS: Data from the Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project was queried for each year from 2002-2011. Patients undergoing an anterior cervical fusion or posterior cervical fusion, anterior lumbar fusion or posterior lumbar fusion, or a posterior thoracic fusion were identified and separated into cohorts. The frequency of BMP utilization was assessed in each surgical cohort by year. Patient demographics, hospital parameters, costs, and mortality rates were assessed.

RESULTS: The adjusted annual number of procedures with BMP increased from 1116 in 2002 to 79,294 in 2011 (P < 0.001), representing 26.9% of all spinal fusion procedures. The rate of BMP utilization within each surgical cohort also significantly increased during the 10-year period (P < 0.001). The posterior lumbar fusion cohort accounted for the majority of spinal fusions that used BMP, representing 76.8% of all spinal fusions between 2002 and 2011. The anterior lumbar fusion cohort was associated with the highest proportion of BMP utilization, peaking at 56.9% of all anterior lumbar interbody fusions in 2006. The trend of BMP utilization in the anterior cervical fusion cohort peaked in 2007 with 10.6% of cases and then declined to 6.4% in 2011. There was a statistically significant trend of older patients with increasing comorbidities receiving BMP during this period. Hospital costs (adjusted for inflation) significantly increased an average of $9560 from 2002-2010. There were no significant trends with regard to the length of hospitalization stay and mortality rates during this period.

CONCLUSION: This nonconflicted study demonstrates that the utilization of BMP has dramatically increased from 2002-2011. Interestingly, off-label application of BMP accounts for the vast majority of BMP utilization. The increase in the total hospital costs is likely multifactorial; older patients with more comorbidities undergoing surgery as well as the increasing utilization of BMP are all likely contributory factors. The length of hospitalization stay and mortality rates did not increase during the 10-year period.