Table 2.

Baseline characteristics of the New Zealand inflammatory bowel disease patients and controls n (%)

Characteristic	Controls	CD	UC	IBD-U
Number of females	340 (63.0)	307 (63.0)	242 (51.5)	13 (50.0)
Age at first diagnosis (yr)
< 17		57 (11.3)	28 (5.9)
17-40		277 (55.0)	231 (48.6)	15 (55)
> 40		170 (33.7)	216 (45.5)	12 (45)
CD location
Colonic		211 (41.8)
Ileocaecal		125 (24.8)
Ileal		64 (32.5)
Isolated upper GI disease		3 (0.6)
Perianal disease modifier		136 (27.0)
CD behaviour
Non-stricturing/ non-penetrating		286 (56.8)
Penetrating		57 (11.3)
Stricturing		161 (31.9)
UC location
Proctitis			164 (34.5)	3 (11.1)
Left-sided			125 (26.3)	5 (18.5)
Extensive			181 (38.1)	19 (70.4)

IBD: Inflammatory bowel disease; UC: Ulcerative colitis; CD: Crohn’s disease; GI: Gastrointestinal.