Myosteatosis and visceral obesity show small associations with minor postoperative complications after colorectal surgery

INTRODUCTION: Despite advancements in perioperative care, patients undergoing colorectal surgery remain at significant risk of developing postoperative complications. Myopenia, myosteatosis and visceral obesity may impair postoperative recovery, however the exact effects are unclear. This substudy from a prospective, randomized controlled trial investigates the effects of myopenia, myosteatosis and visceral obesity on postoperative outcomes and inflammatory markers following colorectal surgery. METHODS: Adult patients undergoing elective colorectal surgery were included from a previous randomized controlled trial (SANICS II; NCT02175979). Preoperative CT images were analyzed to determine skeletal muscle index (SMI), visceral adipose tissue index (VATI) and mean skeletal muscle attenuation. Clinical outcomes and systemic inflammatory markers (interleukin (IL)-6, IL-8, tumor necrosis factor (TNF)-alpha and C-reactive protein (CRP)) were prospectively registered. Univariate and multivariate linear regression analyses were performed to identify significant associations. RESULTS: This study included 219 patients. After adjusting for confounding factors, mean skeletal muscle attenuation (p = 0.038) and VATI (p = 0.003) were significantly associated with the occurrence of any complication. Also, VATI was significantly associated with the occurrence of minor (Clavien-Dindo <3) complications (p = 0.010). In addition, VATI was associated with elevated CRP concentrations on postoperative day 2 (p = 0.020). However, the effect size was small, and all other analyses were not significant. CONCLUSION: Although myosteatosis and visceral obesity affected some postoperative outcomes, these effects were small and did not include major complications following colorectal surgery. The clinical relevance of myopenia, myosteatosis and visceral obesity in surgical convalescence appears to be limited.