Perianal Disease Onset Age is Associated with Need for Abdominal Surgery in Perianal Crohn’s Disease: A Ten-year Observational Study in China

Background: and aims The significance of different ages of perianal disease (PD) onset in patients with perianal Crohn’s disease (PCD) remains unknown. We aimed to investigate the impact of paediatric-onset PD (POP, <18 years) and adult-onset PD (AOP, ≥18 years) on the Crohn’s disease (CD) course in a Chinese cohort. Methods: The medical records of the diagnosed PCD patients from 2008 to 2018 were reviewed retrospectively. The cumulative incidence of abdominal surgery was calculated using the Kaplan-Meier, and independent predictors of surgery were identified by logistic regression analysis. Results: Complex perianal fistulas (71.7% vs 50.0%, p =0.011) and infliximab (IFX) treatment (33.3% vs 22.0%, p =0.044) were more common among the POP patients (n=84). A younger PD onset age (15.1±2.9 vs 30.2±10.5 years, p <0.001) and shorter PCD diagnostic delay (12 vs 24 months, p =0.033) was seen in the POP cohort. AOP patients (n=209) had a higher rate of current smoking (12.9% vs 4.8%, p =0.040), stricturing behaviour (42.1% vs 27.4%, p =0.024) and abdominal surgery (21.1% vs 4.8%, p =0.001). The cumulative probability of abdominal surgery in AOP patients was higher than that in POP patients ( p =0.007). In multivariable analysis, AOP (odds ratio [OR]: 2.915, 95% CI: 1.479-5.744, p =0.002) and stricturing behaviour (OR: 8.374, 95% CI: 1.055-66.488, p =0.044) were predictive factors for CD-related abdominal surgery in all PCD patients, complex perianal fistula was associated with the increased incidence of abdominal surgery in the AOP cohort (OR: 2.257, 95% CI: 1.041-4.891, p =0.039). The IFX administration significantly decreased the rate of abdominal surgery in AOP patients ( r =-0.900, p =0.037). Conclusions: This Chinese cohort suggested that AOP indicate a later disease course and a higher risk of abdominal surgery than POP. Early diagnosis and positive IFX treatment could improve the prognosis of CD patients with AOP.