Low psoas muscle area is associated with postoperative complications in Crohn's disease

Crohn's disease (CD) is associated with increased postoperative morbidity. Sarcopenia correlates with increased morbidity and mortality in various medical conditions. We assessed correlations of the lean body mass marker and psoas muscle area (PMA), with postoperative outcomes in CD patients undergoing gastrointestinal surgery.

We included patients with CD who underwent gastrointestinal surgery between June 2009 and October 2018 and had CT/MRI scans within 8 weeks preoperatively. PMA was measured bilaterally on perioperative imaging.

Of 121 patients, the mean age was 35.98 ± 15.07 years; 51.2% were male. The mean BMI was 21.56 ± 4 kg/m2. The mean PMA was 95.12 ± 263.2cm². Patients with postoperative complications (N = 31, 26%) had significantly lower PMA compared with patients with a normal postoperative recovery (8.5 ± 2.26 cm2 vs. 9.85 ± 2.68 cm2, P = 0.02). A similar finding was noted comparing patients with anastomotic leaks to those without anastomotic leaks (7.48 ± 0.1 cm2 vs. 9.6 ± 2.51 cm2, P = 0.04). PMA correlated with the maximum degree of complications per patient, according to the Clavien-Dindo classification (Spearman's coefficient = -0.26, P = 0.004). Patients with major postoperative complications (Clavien-Dindo ≥ 3) had lower mean PMA (8.12 ± 2.75 cm2 vs. 9.71 ± 2.57 cm2, P = 0.03). Associations were similar when stratifying by gender and operation urgency. On multivariate analysis, PMA (HR = 0.72/cm2, P = 0.02), operation urgency (HR = 3.84, P < 0.01), and higher white blood cell count (HR = 1.14, P = 0.02) were independent predictive factors for postoperative complications.

PMA is an easily measured radiographic parameter associated with postoperative complications in patients with CD undergoing bowel resection.