Effects of coffee consumption, smoking, and hormones on risk for primary sclerosing cholangitis.
OBJECTIVE
Little is known about nongenetic risk factors for primary sclerosing cholangitis (PSC), except a possible protective effect of smoking. We investigated the relationship between environmental risk factors and susceptibility to PSC.


METHODS
A questionnaire was distributed to patients with PSC, recruited from Oslo University Hospital Rikshospitalet in Norway through 2011, and randomly chosen individuals from the Norwegian Bone Marrow Donor Registry (control subjects). Data were analyzed from 240 patients with PSC and 245 control subjects, matched for gender and age.


RESULTS
A lower proportion of patients with PSC were daily coffee drinkers than control subjects, both currently (76% vs 86%; odds ratio [OR], 0.52; 95% confidence interval [CI], 0.32-0.82; P = .006) and at the age of 18 years (35% vs 49%; OR, 0.58; 95% CI, 0.40-0.83; P = .003). The associations were mainly attributed to differences observed in men. Twenty percent of the patients were ever (current or former) daily smokers compared with 43% of control subjects (OR, 0.33; 95% CI, 0.22-0.50; P < .001). Ever daily smoking before PSC diagnosis was associated with older age at diagnosis (42 years vs 32 years; P < .001). Ever daily smoking (P < .001) and being a coffee drinker at the age of 18 years (P = .048) were independently and negatively associated with PSC. Fewer female patients with PSC than control subjects reported ever use of hormonal contraception (51% vs 85%; P < .001). Among female patients, there was a strong correlation between increasing number of children before the diagnosis of PSC and increasing age at diagnosis (r = 0.63; P < .001).


CONCLUSIONS
Coffee consumption and smoking might protect against development of PSC. In women, the disease might be influenced by hormonal factors.
Norwegian PSC Research Center, Department of Transplantation Medicine, Division of Cancer Medicine, Surgery and Transplantation, Oslo University Hospital, Rikshospitalet, Oslo.
Ina Marie
IM
Andersen
Norwegian PSC Research Center, Department of Transplantation Medicine, Division of Cancer Medicine, Surgery and Transplantation, Oslo University Hospital, Rikshospitalet, Oslo.
Guro
G
Tengesdal
Department of Immunology, Oslo University Hospital, Rikshospitalet, Oslo; Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo.
Benedicte Alexandra
BA
Lie
Norwegian PSC Research Center, Department of Transplantation Medicine, Division of Cancer Medicine, Surgery and Transplantation, Oslo University Hospital, Rikshospitalet, Oslo; Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo; Section for Gastroenterology, Department of Transplantation Medicine, Division of Cancer Medicine, Surgery and Transplantation, Oslo University Hospital, Rikshospitalet, Oslo.
Kirsten Muri
KM
Boberg
Norwegian PSC Research Center, Department of Transplantation Medicine, Division of Cancer Medicine, Surgery and Transplantation, Oslo University Hospital, Rikshospitalet, Oslo; Section for Gastroenterology, Department of Transplantation Medicine, Division of Cancer Medicine, Surgery and Transplantation, Oslo University Hospital, Rikshospitalet, Oslo; K. G. Jebsen Inflammation Research Centre, Research Institute of Internal Medicine, Division of Cancer Medicine, Surgery and Transplantation, Oslo University Hospital, Rikshospitalet, Oslo; Division of Gastroenterology, Department of Clinical Medicine, University of Bergen, Bergen, Norway.
Tom Hemming
TH
Karlsen
Norwegian PSC Research Center, Department of Transplantation Medicine, Division of Cancer Medicine, Surgery and Transplantation, Oslo University Hospital, Rikshospitalet, Oslo; Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo; Section for Gastroenterology, Department of Transplantation Medicine, Division of Cancer Medicine, Surgery and Transplantation, Oslo University Hospital, Rikshospitalet, Oslo; K. G. Jebsen Inflammation Research Centre, Research Institute of Internal Medicine, Division of Cancer Medicine, Surgery and Transplantation, Oslo University Hospital, Rikshospitalet, Oslo. Electronic address: j.e.r.hov@medisin.uio.no.
Johannes Roksund
JR
Hov
D000293:Adolescent; D000328:Adult; D000368:Aged; D015209:Cholangitis, Sclerosing / Q000453:epidemiology*; D003069:Coffee; D015331:Cohort Studies; D004198:Disease Susceptibility; D005260:Female; D006728:Hormones / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D018570:Risk Assessment; D012307:Risk Factors; D012737:Sex Factors; D012907:Smoking; D011795:Surveys and Questionnaires; D055815:Young Adult
D003069:Coffee; D006728:Hormones
Coffee; Pregnancy; Primary Sclerosing Cholangitis; Smoking