The gut microbiota in conventional and serrated precursors of colorectal cancer

Microbiome

Table 1 Demographic and polyp characteristics of the study participants

	Controls	CA cases	HP cases	SSA cases
N	323	144	40	33
Male, %	47.1	67.4**	52.5	54.5
Age (years), mean ± SD	61.3 ± 7.2	63.1 ± 6.6*	64.4 ± 7.5*	63.1 ± 7.0
White^a, %	94.4	95.0	92.5	97.0
Family history of cancer^b, %	25.2	29.1	41.0	25.0
BMI category^c, %
Under or normal-weight (BMI <25 kg/m²)	39.9	31.2	32.5	24.2
Overweight (25 ≤ BMI < 30 kg/m²)	38.7	43.1	42.5	45.5
Obese (BMI ≥30 kg/m²)	21.4	25.7	25.0	30.3
Study, %
CDC	75.5	70.1	60.0	87.9
NYU	24.5	29.9	40.0	12.1
Polyp histology^d, %
TA <1 cm only		84.0
TA ≥1 cm, TVA, or TA and TVA only		15.3
Hyperplastic only			100.0
SSA only				81.8
SSA and hyperplastic only				18.2
Polyp location^e, %
Proximal		60.4	15.0	90.9
Distal		38.2	85.0	9.1

CA conventional adenoma, HP hyperplastic polyp, SSA sessile serrated adenoma
*p < 0.05, **p < 0.001, different from controls by Wilcoxon rank-sum test or Chi-squared test for continuous or categorical variables, respectively
^a n = 4 were missing race
^b n = 7 were missing family history
^cThose missing BMI (CDC n = 1, NYU n = 3) were re-coded as the median (CDC 27 kg/m², NYU 25 kg/m²) in order to retain sample size in covariate adjusted analyses
^d TA tubular adenoma, TVA tubulovillous adenoma, SSA sessile serrated adenoma, n = 1 subject with a TA could not be classified by size, so conventional adenoma percentage will not sum to 100%
^eProximal: polyps only in the cecum, ascending colon, hepatic flexure, transverse colon, or splenic flexure; distal: any polyp located in the descending colon, sigmoid colon, or rectum; see Additional file 1: Table S2 for further breakdown by specific location; n = 2 subjects with CAs could not be classified by location, so CA percentage will not sum to 100%

ISSN: 2049-2618