The association of inflammatory bowel disease and immediate postoperative outcomes following lumbar fusion.

BACKGROUND CONTEXT: The United States Centers for Disease Control and Prevention estimates the prevalence of inflammatory bowel disease (IBD) at more than 3.1 million people. As diagnostic techniques and treatment options for IBD improve, the prevalence of IBD is expected to increase. For spine surgeons, patients with IBD have a unique complication profile because patients with IBD may present with poor nutritional status and because the medications used to manage IBD have been associated with poor vertebral bone mineralization and immunosuppression. Presently, there are very limited data regarding perioperative outcomes among patients with IBD who undergo spinal surgery. The present study begins to address this knowledge gap by describing trends in patients with IBD undergoing lumbar fusion and by quantifying the association between IBD and immediate postoperative outcomes using a large, national database.

PURPOSE: To advance our understanding of the potential pitfalls and risks associated with lumbar fusion surgery in patients with IBD.

DESIGN/SETTING: Retrospective cross-sectional analysis.

PATIENT SAMPLE: The Nationwide Inpatient Sample (NIS) database was queried from 1998 to 2011 to identify adult patients (18+) who underwent primary lumbar fusion operations using International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) coding.

OUTCOME MEASURES: Incidence of lumbar fusion procedures, prevalence of IBD, complication rates, length of stay, and total hospital charges.

METHODS: The annual number of primary lumbar fusion operations performed between 1998 and 2011 was obtained from the NIS database. Patients younger than 18 years of age were excluded. The prevalence of IBD in this population (both Crohn disease and ulcerative colitis) was determined using ICD-9-CM codes. Logistic regression models were estimated to determine the association between IBD and the odds of postoperative medical and surgical complications, while controlling for patient demographics, comorbidity burden, and hospital characteristics. The complex survey design of the NIS was taken into account by clustering on hospitals and assuming an exchangeable working correlation using the discharge weights supplied by the NIS. We accounted for multiple comparisons using the Bonferroni correction and an alpha level for statistical significance of . 0028.

RESULTS: The prevalence of IBD is increasing among patients undergoing lumbar fusion, from 0.21% of all patients undergoing lumbar fusion in 1998 to 0.48% of all patients undergoing lumbar fusion in 2011 (p<.001). The odds of experiencing a postoperative medical or surgical complication were not significantly different when comparing patients with IBD with control patients without IBD after controlling for patient demographics, comorbidity burden, and hospital characteristics (adjusted odds ratio=1.1, 95% confidence interval [CI] 0.99-1.3, p=.08). On multivariable analysis, the presence of IBD in patients undergoing lumbar fusion surgery was associated with longer length of stay and greater hospitalization charges.

CONCLUSIONS: Among patients who underwent lumbar fusion, IBD is a rare comorbidity that is becoming increasingly more common. Importantly, patients with IBD were not at increased risk of postoperative complications. Spine surgeons should be prepared to treat more patients with IBD and should incorporate the present findings into preoperative risk counseling and patient selection.