P597. Reduced recurrence rates in Crohn's disease in the era of biological therapy: A 7-year population-based follow-up study of inflammatory bowel disease
To evaluate the cumulative probability of recurrences in a population-based cohort and to assess the association with baseline factors.
Data on medication prescription and phenotypic appearance in 513 individuals [ulcerative colitis (UC) n = 300, Crohn's disease (CD) n = 213] diagnosed in 2003–2004 with a follow-up time of 7 years were defined as baseline factors. Cumulative probabilities of recurrences were estimated and the association of baseline factors, medication use and time to first recurrence were examined by Cox regression.
In CD the cumulative risk of first all type recurrence was 42%, 67% and 69% after 1, 5 and 7 years. 55% of the patients at risk had a second relapse within 2 years of the first and of these 53% had third relapse within one year of the second. The cumulative risk of medical relapses were 38%, 62% and 65% after 1, 5 and 7 years. There was a trend of a protective factor in having male gender (HR 0.73 95% CI: 0.51–1.04) and use of thiopurines (HR 0.69, 95% CI: 0.44–1.06) in medical relapses. Stricturing behaviour at diagnosis (HR 3.5; 95% CI: 3.5–7.2), use of systemic corticosteroids (HR 3.77; 95% CI: 1.17–12.15), thiopurines (HR 1.90 95% CI: 1.03–3.50) and anti-TNF agents (HR 2.37; 95% CI: 1.21–4.65) were associated with first surgical recurrence. Localization in the colon (HR 0.37; 95% CI: 0.18–0.72) and ileocolon (HR 0.41; 95% CI: 0.19–0.90) were protective. In UC the cumulative risk of first all type recurrence was 53%, 76% and 80% in 1, 5 and 7 years. The cumulative risk of a medical recurrence was 52%, 74% and 78% in 1, 5 and 7 years. Age above 40 was protective in first all type recurrence (HR 0.64; 95% CI: 0.49–0.84), in medical recurrence (HR 0.69; 95% CI: 0.52–0.90) and against colectomy (HR 0.49 95% CI: 0.22–1.09). Use of systemic corticosteroids in the first three months after diagnosis (HR 4.56; 95% CI: 2.09–9.95), use of thiopurines (HR 9.71; 95% CI: 4.58–20.57) and use of anti-TNF (HR 12.38; 95% CI: 4.33–35.37) were all significantly associated to risk of colectomy.
The cumulative risk of first all type recurrence has decreased in CD compared to previous studies but patients with a relapse are at risk of a second and third relapse. Stricturing behaviour, systemic corticosteroids, thiopurines and anti-TNF were associated with first surgical recurrence. In UC the cumulative recurrence rate was unaltered. Age above 40 was protective against any type of recurrence.