Influence of gender on discharge disposition after spinal fusion for adult spine deformity correction

Abstract

Objectives: Gender has been shown to impact several aspects of spine surgical care. However, the influence of gender disparities on discharge disposition after adult spine deformity correction (ASD) is relatively understudied. The aim of this study was to investigate the influence of gender on discharge disposition after elective spinal fusion involving ≥4 levels for ASD correction.

Patients and methods: The Nationwide Inpatient Sample database (2011-2014) was queried for patients with ASD (≥26 years-old) and elective spine fusion surgery involving ≥4 levels using ICD-9 codes. Patients were stratified by gender: Male or Female. Multivariate linear and logistic regressions were used to assess the impact of gender on length of hospital stay and discharge disposition.

Results: A total of 4972 patients were identified of which 3282 (66.0%) were Female and 1690 (34.0%) were Male. The Male cohort had a higher prevalence of comorbidities than the Female cohort. There was a difference in the number of levels operated on between cohorts, with the Female cohort having fewer 4-8-level fusions (77.6% vs. 86.8%) and more 9+-level fusions (23.0% vs. 13.6%) compared to Males. The Female cohort had greater rates of postoperative UTI (5.5% vs. 2.5%) and surgical site hematomas (2.6% vs. 1.3%), while the Male cohort had more postoperative MI (5.4% vs. 1.5%). The Female cohort spent slightly more time in the hospital than Male cohort (6.2 days vs. 5.9 days, P = 0.035). Female patients had a significantly greater proportion of non-routine discharge disposition (F: 48.5% vs. M: 40.3%, P < 0.001) compared to Male patients. However, in a multivariate analysis including patient and hospital factors, gender was not an independent predictor of discharge disposition (OR: 0.976, CI: 0.865-1.101, P = 0.688), but was independently associated with increased LOS [female (RR: 0.331, CI: 0.106-0.556, P = 0.004)].

Conclusion: Our study suggests gender disparities may not have a significant impact on discharge disposition after spinal fusion for ASD involving four levels or greater. Further studies are necessary to understand risk factors for non-routine discharges in ASD patients to improve quality of patient care and reduced healthcare costs.

Keywords: Adult spine deformity; Discharge disposition; Gender; Healthcare expenditure; Nationwide Inpatient Sample database; Spinal fusion.