Crude and adjusted HR and 95% CIs for IBD in relation to increasing number of antibiotic prescriptions
| Systemic antibiotics, filled prescriptions | IBD | ||
| n | cHR (95% CI) | aHR (95% CI) | |
| 1 | 6 | 0.73 (0.28 to 1.92) | 0.73 (0.28 to 1.89) |
| 2 | 9 | 1.87 (0.81 to 4.34) | 1.85 (0.80 to 4.30) |
| ≥3 | 10 | 1.15 (0.48 to 2.75) | 1.12 (0.47 to 2.65) |
aHR - 3 874 000 person-years; analyses adjusted for mother’s and father’s history of IBD, parental education, mother’s and father’s country of birth and mode of delivery. Those with missing information on these variables are excluded (no cases excluded).
cHR - 3 945 000 person-years.
n, cases, ie, those who have been exposed to antibiotics prior to onset of IBD diagnosis.
aHR, adjusted HR; cHR, crude HR.