Table 1.

Phenotype distributions of discovery and replication cohorts.

	Cohort A	Cohort B
Characteristic	[n = 1097]	[n = 2156]	p-values
Sex, no. [%]			0.35
Female	559 [57%]	1266 [59%]
Age, median [IQR], years	48 [36–60]	44 [33–56]	<1.0E-04
Type of IBD diagnosis, no. [%]			<1.0E-04
Crohn’s disease	506 [52%]	1393 [65%]
Ulcerative colitis	417 [43%]	763 [35%]a
IBD-unclassified	48 [5%]	NA
Montreal A			0.04
A1	79 [16%]	209 [15%]
A2	320 [65%]	977 [70%]
A3	96 [19%]	207 [15%]
Montreal L			<1.0E-04
L1	179 [58%]	187 [18%]
L2	101 [33%]	368 [34%]
L3	26 [9%]	514 [48%]
L4 [upper GI involvement]	51 [17%]	112 [10%]	0.16
Montreal B			<1.0E-04
B1	238 [48%]	927 [67%]
B2	178 [36%]	270 [19%]
B3	82 [16%]	196 [14%]
Bp	156 [31%]	381 [27%]	0.14
Montreal E			0.02
E1	45 [11%]	39 [6%]
E2	135 [32%]	230 [37%]
E3	242 [57%]	361 [57%]
Primary sclerosing cholangitis	78 [7%]	42 [2%]	<1.0E-04
Surgery
Colonic resection	349/980 [36%]	408 [19%]	<1.0E-04
Ileocaecal resection	180/980 [18%]	525 [24%]	2.0E-04
Smoking status
Current	190/942 [19%]	397 [29%]	0.09
Former	516/910 [53%]	698 [36%]	<1.0E-04
Ever	575/980 [59%]	836 [43%]	<1.0E-04
Extra-intestinal manifestations
Ocular manifestations	35 [3%]	103 [5%]	0.033
Cutaneous manifestations	147 [13%]	229 [11%]	0.019
Arthropathies	304 [28%]	410 [19%]	<1.0E-04
Arthritis	42 [4%]	150 [7%]	3.4E-04
Thromboembolism	12 [1%]	81 [4%]	<1.0E-04
Osteoporosis	59 [5%]	452 [21%]	<1.0E-04

Characteristics of patients with IBD from the discovery cohort [cohort A] and replication cohort [cohort B]. Percentages were calculated from non-missing data. Montreal refers to the Montreal classification.¹⁵

GI, gastrointestinal; IBD, inflammatory bowel disease; IQR, inter-quartile range; NA, not available.

^aUC and IBD-unclassified were grouped in cohort B.