Table 1  Demographics and clinical features of the Crohn’s disease (CD), ulcerative colitis (UC), and control groups

Crohn’s disease (n = 374) Ulcerative colitis (n = 305) Controls (n = 294)

Sex (M/F) 181/193 171/134 143/151
Age at diagnosis (y) (median (IQR)) 27.8 (20.9–40.4) 34 (25–50) 39 (27–52)
Duration of follow up (y) (median (IQR)) 11.8 (6.5–20.2) 7.5 (3.35–13.38)
Caucasian (%) 98.7% 98.3%
CD location at diagnosis UC disease extent
    Ileal disease 125 (36%)  Proctitis 105 (34.5%)
    Colonic disease 137 (39%)  Left sided colitis 116 (37%)
    Ileal and colonic 58 (14%)  Extensive colitis 84 (27.5%)
    Upper GI disease 30 (8.5%)
    Perianal disease 75 (21.4%)
CD location at follow up
    Ileal disease 92 (25%)
    Colonic disease 130 (35%)
    Ileal and colonic 103 (28%)
    Upper GI disease 49 (13%)
CD behaviour at diagnosis
    Inflammatory (Vienna B1) 258 (74.8%)
    Stricturing (Vienna B2) 30 (8.4%)
    Penetrating (Vienna B3) 59 (16.8%)
CD behaviour at follow up
    Inflammatory (Vienna B1) 142 (38%)
    Stricturing (Vienna B2) 68 (18%)
    Penetrating (Vienna B3) 164 (44%)

IQR, interquartile range.