DOP42 Disease course and clinical outcomes in Taiwan Crohn’s Disease patients with perianal fistula: A nationwide-based study

Weng, M.T.(1);Lin, K.L.(2);Chan, K.A.(3);Wei, S.C.(4)

(1)National Taiwan University Hospital, Department of Internal Medicine, Taipei, Taiwan- Province Of China;(2)National Taiwan University, Health Data Research Center, Taipei, Taiwan- Province Of China;(3)National Taiwan University, Health Data Research Center, Taipeit, Taiwan- Province Of China;(4)National Taiwan University Hospital, Departments of Internal Medicine, Taipei, Taiwan- Province Of China

Background

Perianal fistula (PAF) is a disabling complication of Crohn’s disease (CD) and there are few reports about the disease course in Asian population in a population based nationwide scale. We aimed to evaluate the prevalence, clinical course and outcomes of PAF in Taiwanese CD population.

Methods

By using data from the National Health Insurance, we defined the CD patients and PAF by the ICD coding and filtered by the medication and surgery history. The prevalence, the fistula disease course was analyzed and the outcomes were compared to the CD patients without PAF.

Results

In this nationwide cohort study, from 2000 to 2017, PAF was diagnosed in 358 (14.6 %) of 2444 CD patients. The majority of CD patients with PAF were men (79.3%). The age of diagnosis for CD was younger in PAF patients (33.7 ± 14.9 years) than those without PAF (45 ± 21.8 years). Approximately half of the PAF occurred before (47.5%) the diagnosis of CD. 33.8% (121/358) patients had recurrent fistula with a median recurrent interval of 239 days (IQR 68-902 days). For CD patients with PAF, they received more often medical treatment including 5-ASA (93.9 vs 67.7 %, p < 0.0001), steroid (94.4 vs 89 %, p < 0.0018), azathioprine (61.7 vs 31.2 %, p < 0.0001) and anti-TNF alpha (44.4 vs 15.1 %, p < 0.0001) and had higher risk of operation (1.4 vs 1.2, p < 0.0032), hospitalization (6.4 vs 3.8, p < 0.0001), Out Patient Clinic (22 vs 6.7, p < 0.0001) and emergency visits (9.7 vs 4.5, p < 0.0001), compared to those without PAF. Although the PAF group needs higher health care utility, the mortality rate is lower than those without PAF (6.7% vs 18.7%, p < 0.0001). Those PAF diagnosed earlier than CD had lower risk of hospitalization (5.1 vs 7.5, p =0.0005) and ER visit (6.3 vs 12.3, p = 0.0056) than PAF diagnosed at the same time or after CD diagnosis. With early use of biologics, patient is associated with lower risk of hospitalization (4.7 vs 9.1, p <0.0001) and ER visit (4.9 vs 13.6, p =0.0116).

Conclusion

By using the nationwide population database, the prevalence of PAF in Taiwanese CD patients is 14.6 %. The fistula recurrence rate was 33.8%. Patients with PAF required more intensive care and consume more medical resources but they did not have poorer survival status compared to those who do not have PAF. Approximately half of PAF patients presented with perianal symptoms before the diagnosis of CD. Early use of biologics can decrease hospitalization and emergency visit.