M. M. Romine1,2, A. Gullick1,2, M. Morris1,2, L. Goss1,2, D. Chu1,2 1University Of Alabama at Birmingham,Gastrointestinal Surgery,Birmingham, Alabama, USA 2VA Birmingham HealthSystem,General Surgery,Birmingham, AL, USA
Introduction:
Controversy persists on the association of Body Mass Index (BMI) with SSI in patients with IBD. Previous studies have been limited by single-institution populations and mixing of Crohn’s disease and Ulcerative Colitis (UC) patients. In this study, we aim to use a national dataset to investigate the association of BMI with SSI specifically in patients with UC. We hypothesize that higher BMI is associated with higher risk for SSI.
Methods:
Using the 2012-2014 ACS-NSQIP Procedure Targeted Database, we identified all patients with UC who underwent colectomy between 2012-2014. Patients with UC were stratified by weight status to underweight, normal weight, overweight and BMI class I (30-34.9), II (35-39.9) and III (>40). Patient demographics, preoperative comorbidities and surgical characteristics were compared. Primary outcomes were wound complications (SSI, organ space SSI, anastomotic leaks) and secondary outcomes were other reported NSQIP-complications. Multivariate analysis was used to identify predictors for wound complications.
Results:
Of 1,487 patients with UC, 39.8% were classified as normal weight as compared to 25.4%, 14.9%, 6.59% and 3.43% for overweight, BMI class I, II and III, respectively. Overall, 10.96% of patients were smokers, 9% of patients were diabetic and 65.77% of patients were on steroids or other immunosuppressant. Patients with higher BMI class were more likely to have diabetes: 6.31% in class I, 10.2% in class II and 13.73% in class III (p value <0.001). At time of surgery, a larger percentage of class III obese patients (27.45%) were classified as ASA 4-5 (p value <0.001). Higher BMI was associated with greater rates of SSI: 7.25% in normal weight class, 8.7% in the overweight class, 9.01% in class I, 18.37% in class II and 27.45% in class III (p-value<0.001). There was no significant difference in organ space SSI (range: 3.92-7.94%) and anastomotic leaks (range: 1.35-6.12%) between the BMI classes (p>0.05). There was an increase in sepsis rate (33.3% vs 15.3%] and respiratory complication rates (23.5% vs 10.2%) with BMI class III vs BMI class II and continued to decrease with the lower classes (p-value<0.001). On adjustment for covariate differences, BMI remained a significant predictor for SSI with the highest odds in class III (OR 5.0 CI 2.5-10.2) and Class II obesity (OR 3.5 CI 1.9-6.4) when compared to normal BMI individuals.
Conclusion:
Patients with UC and high BMI are at the highest risk for SSI but not for organ space SSI or anastomotic leak rates. Targeting BMI with weight-loss strategies may be one actionable opportunity to reduce post-operative SSI rates.