32. Does the number of patient-reported allergies impact clinical outcomes after lumbar spinal fusion?

Abstract

BACKGROUND CONTEXT A gap in the literature exists regarding the association of clinical and radiographic outcomes with specific number of allergies for patients undergoing lumbar spinal fusions; which is necessary to close in order to better understand the prognostic value of patient-reported allergies. PURPOSE The purpose of this present study was therefore to determine the impact of specific number of allergies with clinic and radiographic outcomes following lumbar spinal fusion. STUDY DESIGN/SETTING Retrospective cohort analysis. PATIENT SAMPLE Analysis of patients who underwent an open posterior lumbar fusion from 2011 to 2017 was conducted. Surgery was indicated after failure of conservative treatment to address radiculopathy and/or neurogenic claudication. Patients were excluded if they were under 18 years of age at the time of surgery, presented with a lumbar vertebral body fracture, tumor, or infection, or underwent a fusion surgery that extended to the thoracic spine, high-grade spondylolisthesis, or concomitant deformity. OUTCOME MEASURES Patient-reported outcomes were recorded at preoperative and final clinic visits that included: Visual Analog Scale (VAS) Back/Leg pain, and Oswestry Disability Index (ODI). Achievement of minimal clinically important difference (MCID) was analyzed, along with rates of postoperative complication and reoperation. METHODS Preoperative and final patient-reported outcomes were obtained. Achievement of MCID was evaluated using following thresholds: ODI 14.9, VAS-back pain 2.1, VAS-leg pain 2.8. For analysis, patients were divided into two groups based on number of allergies: less than three allergies and greater than or equal to three allergies. RESULTS A total of 504 patients met inclusion criteria. There were 472 (93.65%) patients who reported fewer than three allergies, while 32 (6.35%) patients presented with three or more allergies. Patients with three or more reported allergies were more often older (p=0.026), female (p CONCLUSIONS Patients with more than three reported allergies have significantly less improvement of ODI scores from preoperative to final assessment and have significantly high ODI MCID scores postoperatively despite no significant difference in psychiatric condition or radiographic measurements between the two groups. These results suggest a lower perceived improvement of disability in patients with more than three reported allergies when compared with patients with a lower number of allergies. This study underscores the importance of considering the number of allergies as a prognostic factor, similar to psychiatric disorders. Furthermore, these findings can be used in discussion with patients regarding expectations of disability improvement prior to surgery. FDA DEVICE/DRUG STATUS This abstract does not discuss or include any applicable devices or drugs.