Table 3.

Relationship between smoking habit, appendectomy, or tonsillectomy, and all patients with primary sclerosing cholangitis (PSC)

	PSC	Controls*	Odds ratio†	95% CI	p Value
Smoking
Never	112 (66%)	66 (39%)	1.0
Ever	58 (34%)	104 (61%)	0.33	0.21–0.52	<0.001
Former	46 (27%)	61 (36%)	0.45	0.26–0.73	<0.05
Current	12 (7%)	43 (25%)	0.17	0.08–0.35	<0.001
Appendectomy
No	146 (86%)	148 (87%)
Yes	24 (14%)	22 (13%)	1.11	0.57–2.2	NS
Tonsillectomy
No	135 (79%)	117 (69%)
Yes	35 (21%)	53 (31%)	0.57	0.34–0.96	0.05

*Controls matched to PSC patients in terms of age/sex/locality.

†Odds of having PSC relative to never smokers.