The main goals of this study are (1) to determine whether current and past use of oral contraceptives alter a woman's risk of developing ulcerative colitis (2) to determine whether alteration in risk due to oral contraceptive use varies according to durations of use, timing of use, or the estrogen/progestin content of the preparation(s) used; and (3) to determine whether any change in risk due to oral contraceptive use is confounded or modified by other exposures, illnessess, or personal characteristics. To accomplish these aims a population based case-control study will be conducted among members of a pre-paid health plan serving residents of Washington State (Group Health Cooperative). Cases will be identified by review of medical records and computer files of hospital discharge summary diagnoses. Pharmacy computerized data will be reviewed for all persons who received a prescription for sulfasalazine, a medication primarily used for the treatment of ulcerative colitis. Ongoing surveillance for incident cases of ulcerative colitis will be performed by the Group Health Cooperative (GHC) gastroenterologists for a period of four years. Four female-age matched controls per case will be randomly selected from the GHC enrollment file. Subjects will be interviewed in person about current and past use of oral contraceptives and about other relevant exposures and characteristics, such as childbearing history, socioeconomic status, indication for use of oral contraceptives, and smoking history. A previously validated interview instrument for measurement of oral contraceptive use will be employed. Traditional methods for matched analysis and conditional logistic regression will be used to estimate the odds ratio for ulcerative colitis among oral contraceptive users while adjusting for potential confounding factors.

Agency
National Institute of Health (NIH)
Institute
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
Type
First Independent Research Support & Transition (FIRST) Awards (R29)
Project #
5R29DK039616-05
Application #
3463255
Study Section
Epidemiology and Disease Control Subcommittee 2 (EDC)
Project Start
1989-09-01
Project End
1994-08-31
Budget Start
1992-09-01
Budget End
1994-08-31
Support Year
5
Fiscal Year
1992
Total Cost
Indirect Cost
Name
University of Washington
Department
Type
Schools of Medicine
DUNS #
135646524
City
Seattle
State
WA
Country
United States
Zip Code
98195
Boyko, E J; Theis, M K; Vaughan, T L et al. (1994) Increased risk of inflammatory bowel disease associated with oral contraceptive use. Am J Epidemiol 140:268-78