Number of cases of Crohn’s disease and ulcerative colitis, incidence rates per 100 000 population, and average annual percentage changes in incidence rates with their 95% confidence intervals, overall and by age group and sex, for period 1979–1998
| Sex/age group | Number of cases | Rate | % Change per year | 95% Confidence interval |
|---|---|---|---|---|
| Crohn’s disease | ||||
| All | 1959 | 5.9 | 0.08 | –0.7 to 0.9 |
| Age in years | ||||
| <15 | 52 | 0.8 | –0.3 | –4.9 to 4.5 |
| 15–24 | 406 | 8.3 | 0.4 | –1.4 to 2.2 |
| 25–34 | 472 | 9.2 | 1.0 | −0.6 to 2.7 |
| 35–44 | 305 | 6.5 | 0.1 | −1.9 to 2.2 |
| 45–54 | 228 | 5.7 | 0.7 | −1.5 to 3.1 |
| ≥55 | 496 | 6.6 | −1.4 | −2.9 to 0.2 |
| Males | 749 | 4.6 | 0.05 | −1.2 to 1.3 |
| Females | 1210 | 7.3 | 0.09 | −0.9 to 1.1 |
| Ulcerative colitis | ||||
| All | 2018 | 6.1 | 0.10 | −0.7 to 0.9 |
| Age in years | ||||
| <15 | 38 | 0.6 | −1.0 | −6.3 to 4.7 |
| 15–24 | 216 | 4.4 | 1.1 | −1.4 to 3.6 |
| 25–34 | 344 | 6.7 | 1.3 | −0.6 to 3.2 |
| 35–44 | 313 | 6.7 | −0.1 | −2.0 to 1.9 |
| 45–54 | 266 | 6.7 | −0.6 | −2.7 to 1.5 |
| ≥55 | 841 | 11.1 | –0.3 | –1.4 to 1.0 |
| Males | 962 | 5.9 | 0.7 | –0.5 to 1.9 |
| Females | 1056 | 6.4 | –0.4 | –1.5 to 0.7 |