Body Mass Index Is a Marker of Nutrition Preparation Sufficiency Before Surgery for Crohn's Disease From the Perspective of Intra-Abdominal Septic Complications: A Retrospective Cohort Study

Poor preoperative nutritional status for individuals with Crohn's disease (CD) is associated with intra-abdominal septic complications (IASCs). The present study aimed to investigate the association of the common nutrition indices serum albumin and body mass index (BMI) with IASCs. Sixty-four CD patients who had received elective intestinal operations were retrospectively investigated. Among these patients, 32 had received individualized fortified nutrition support. IASCs occurred in 7 patients (10.9%). Compared with non-IASC patients, IASC patients had a lower BMI (17.6 ± 2.7 vs 15.6 ± 1.3 kg/m(2), P = 0.048). The area under the receiver operating characteristic curve according to the BMI-based IASC prediction was 0.772 (95% confidence interval [CI], 0.601–0.944; P = 0.020) with an optimum diagnostic cutoff value of 16.2 kg/m(2). A BMI < 16.2 kg/m(2) significantly increased the risk of developing an IASC (odds ratio [OR], 10.286; 95% CI, 1.158–91.386). Even after correction with the simplified CD activity index (CDAI), a low BMI level remained associated with IASCs (OR, 7.650; 95% CI, 0.808–72.427; P = 0.076). Serum albumin was not associated with IASCs. Although the fortified nutrition support group had an albumin level comparable to the control group, this group had a higher simplified CDAI score, a lower BMI level, and a comparable incidence rate of IASCs. Thus, BMI more accurately reflects the basic preoperative nutritional status of CD patients than serum albumin. BMI can aid in guiding preoperative nutrition support and judging the appropriate operation time for CD.