Rheumatoid Arthritis Increases Risk of Medical Complications Following Posterior Lumbar Fusion.

BACKGROUND: Rheumatoid arthritis (RA) is a systemic disease with prominent musculoskeletal manifestations that is associated with increased morbidity and mortality in patients undergoing cervical spine surgery; however, few studies have specifically examined postoperative outcomes in patients with RA following lumbar surgery. The aim of this study was to evaluate whether patients with RA who underwent posterior lumbar fusion experienced increased postoperative complications and economic burden compared with patients without RA.

METHODS: Patients <85 years old who underwent elective 1- or 2-level instrumented posterior lumbar fusion for degenerative lumbar pathology between 2006 and 2012 were identified in the Medicare insurance claims database. Same-day revisions and cases for spinal infection, malignancy, and trauma were excluded. The resulting cohort was divided into patients with RA before fusion and patients without RA (controls). All outcomes of interest were compared using multivariate regression. Reoperation-free survival at 1- and 2-year follow-up was analyzed used log-rank test. Significance was defined as P < 0.05.

RESULTS: RA patients had significantly higher risk of 90-day readmission (odds ratio [OR] = 1.27, P < 0.001), thromboembolic events (OR = 1.39, P = 0.010), sepsis (OR = 2.32, P < 0.001), pneumonia (OR = 1.57, P = 0.001), and wound complications (OR = 1.41, P < 0.001). Reoperation-free survival was significantly lower in RA patients at 2-year follow-up (90.4% vs. 92.4%, P < 0.001). Following adjusted regression, RA independently contributed to a $1491 increase in additional 90-day costs (P < 0.001).

CONCLUSIONS: Preexisting RA may increase risk for short-term postoperative medical complications following posterior lumbar fusion, specifically infectious events. In addition, patients with RA have higher rates of subsequent reoperation following index surgery. Patients with RA be should counseled regarding these risks.