133. Cost effectiveness of adult lumbar scoliosis surgery: an as-treated analysis from the adult symptomatic scoliosis surgery trial with five-year follow-up

BACKGROUND CONTEXT Adult spinal deformity is a relatively prevalent condition for which surgical treatment has become increasingly common but concerns surrounding complications, revision rates and cost-effectiveness remain unresolved. Of these issues, cost-effectiveness is perhaps the most difficult to quantify as the requisite data is difficult to obtain. PURPOSE The purpose of this study is to report on the cost-effectiveness of surgical vs nonsurgical treatment for adult symptomatic lumbar scoliosis (ASLS) using the as-treated data and provide a comparison to previously reported intent-to-treat (ITT) analysis. STUDY DESIGN/SETTING Secondary analysis of data from the NIH sponsored study on ASLS that included randomized and observational arms. PATIENT SAMPLE Patients enrolled in the NIH sponsored study on ASLS that included randomized and observational cohorts with at least five-year follow-up data within the same treatment arm. OUTCOME MEASURES Quality Adjusted Life Years (QALY) derived from the SF-6D. METHODS Patients with at least five-year follow-up data within the same treatment arm were included. Data collected every three months included use of nonoperative modalities, medications and employment status. Costs for surgeries and nonoperative modalities were determined using Medicare allowable rates. Medication costs were determined using the RedBook and indirect costs were calculated based on reported employment status and income. Quality Adjusted Life Years (QALY) was determined using the SF-6D. RESULTS Of 286 patients, 195 patients (73 Nonop, 122 Op) met inclusion criteria. At five years, 29 (24%) patients in the Op group had a revision surgery of whom two had two revisions and one had three revisions. The cumulative cost for the Op group was $111,451 with a cumulative QALY gain of 2.29. The cumulative cost for the Non-Op group was $29,124 with a cumulative QALY gain of 0.41. This results in an ICER of $44,033 in favor of Op treatment. CONCLUSIONS This as-treated cost effectiveness analysis demonstrates that surgical treatment for adult lumbar scoliosis becomes favorable at year-three, one year earlier than suggested by a previous intent-to-treat analysis. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.