Demographic characteristics of incident IBD cases and matched controls
| Variable | Cases | Controls |
|---|---|---|
| Total, n | 442 | 940 |
| Crohn's disease, n (%) | 186 (42) | – |
| UC, n (%) | 256 (58) | – |
| Gender, male, n (%) | 258 (58) | 517 (55) |
| Median age, years (range) | 38 (25–50) | 39 (26–53) |
| Ethnicity | ||
| Asian, n (%) | 374 | 789 |
| Han Chinese | 284 (76) | 606 (77) |
| Indonesian | 5 (1) | 10 (1) |
| Thai | 30 (8) | 60 (8) |
| Ethnic Sinhalese | 55 (15) | 113 (14) |
| Caucasian | 68 | 151 |