Opportunistic use of radiological measures of visceral adiposity for assessment of risk of colorectal adenoma

Abstract

Background: Recent evidence suggested that radiological measures of visceral adiposity are a better tool for risk assessment of colorectal adenomas. The aim of this study was to investigate the association of visceral adiposity with the development of colorectal adenomas. Methods: A retrospective review of all cases of computed tomography-confirmed acute diverticulitis from November 2015 to April 2018 was performed. Data collated included basic demographics, computed tomography scan results (uncomplicated versus complicated diverticulitis), treatment modality (conservative versus intervention), outcomes and followup colonoscopy results within 12 months of presentation. The patients were divided into no adenoma (A) and adenoma (B) groups. Visceral fat area (VFA), subcutaneous fat area (SFA) and VFA/SFA ratio (V/S) were measured at L4/L5 level. Statistical analysis was performed to evaluation the association of VFA, SFA, V/S and different thresholds with the risk of adenoma formation. Results: A total of 169 patients were included in this study (A:B = 123:46). The mean ± standard deviation for VFA was higher in group B (201 ± 87 cm 2 versus 176 ± 79 cm 2) with a trend towards statistical significance (P = 0.08). There was no difference in SFA and V/S in both groups. When the VFA >200 cm 2 was analysed, it was associated with a threefold risk of adenoma formation (odds ratio 2.7, 95% confidence interval 1.35-5.50, P = 0.006). Subgroup analysis of gender with VFA, SFA and V/S found that males have a significantly higher VFA in group B (220.0 ± 95.2 cm 2 versus 187.3 ± 69.2 cm 2 ; P = 0.05). Conclusions: The radiological measurement of visceral adiposity is a useful tool for opportunistic assessment of risk of colorectal adenoma.