1462. A Propensity-Matched Analysis of Outcomes and Costs in Adult Patients with Movement Disorders Undergoing Spinal Deformity Surgery
Authors: Arjun Vivek Pendharkar, MD; Kunal Varshneya, BS; Allen Ho, MD; Eric Sussman, MD; Paymon Rezaii, BS; Atman Desai, MD; John Ratliff, MD; Anand Veeravagu, MD (Stanford, CA)
Introduction: Quality improvement efforts in deformity surgery must focus on appropriate patient selection to optimize outcomes. The presence of a concurrent movement disorder (MD), is one emerging factor of interest. The objective of this study was to investigate the perioperative outcomes of patients with MD after deformity surgery. Methods: MarketScan data were queried to identify adult MD patients undergoing deformity surgery. A 1:4 experimental to control propensity score match was conducted to create two uniform cohorts and mitigate inter-population confounders. Perioperative complication rates, 90-day postoperative outcomes such as readmission and reoperation, and total costs were calculated. Results: 316 MD patients (1.7%) were identified from 18970 undergoing spinal deformity surgery. Forty-four percent of MD deformity patients were over the age of 65, compared to 31% in the control (non-MD) group (p < 0.0001). MD patients also had higher rates of osteoporosis (6.7% vs 3.0% p = 0.002) and use of rhBMP-2 (17.1% vs 11.0% p = 0.0006). At 90-days, patients with MD were more likely to be readmitted and have a higher total cost (17.4% vs 13.2% and $94,672 vs $85,190 respectively, p < 0.05). There was a slightly higher observed reoperation rate for MD patients at 90- days, but this was not statistically significant. After propensity score matching, all baseline characteristics were consistent among groups including age, gender, rates of diabetes and myocardial infarction, congestive heart failure, osteoporosis, Charlson- Comorbidity Index Scores, and use of a blood transfusion or recombinant protein. The overall propensity-matched complication rate remained statistically higher in the MD group (44.6% vs 37.6%, p < 0.05). 90-day readmissions and costs also remained significantly higher in the MD cohort. No significant difference in hospital stay was observed. Conclusion: Patients with MD undergoing spinal deformity surgery may be at risk of higher perioperative complications and 90-day readmissions.