RT Journal Article SR Electronic T1 Risk factors for extensive ulcerative colitis and ulcerative proctitis: a population based case-control study. JF Gut JO Gut FD BMJ Publishing Group Ltd and British Society of Gastroenterology SP 1526 OP 1530 DO 10.1136/gut.32.12.1526 VO 32 IS 12 A1 S M Samuelsson A1 A Ekbom A1 M Zack A1 C G Helmick A1 H O Adami YR 1991 UL http://gut.bmj.com/content/32/12/1526.abstract AB To examine socioeconomic factors, dietary and other personal habits, and medical history as risk factors for ulcerative colitis, we studied 167 (98%) of all prevalent cases of ulcerative colitis diagnosed in Uppsala county from 1945 to 1964 and 167 age and sex matched population controls. Ulcerative colitis patients were less likely than controls to be current cigarette, pipe, or cigar smokers (odds ratio (OR) = 0.44; 95% confidence limits (CL) = 0.25-0.78), but more likely to have symptoms induced by drinking milk (OR = 4.63; 95% CL = 2.15-9.93). Patients with ulcerative colitis do not differ in most of the socioeconomic, dietary and personal habits compared with the background population.