Evolution of disease phenotype in adult and pediatric onset Crohn's disease in a population-based cohort

AIM:To investigate the evolution of disease phenotypein adult and pediatric onset Crohn’s disease(CD) populations,diagnosed between 1977 and 2008.METHODS:Data of 506 incident CD patients were analyzed(age at diagnosis:28.5 years,interquartile range:22-38 years).Both in-and outpatient records were collected prospectively with a complete clinical follow-up and comprehensively reviewed in the population-based Veszprem province database,which included incident patients diagnosed between January 1,1977 and December 31,2008 in adult and pediatric onset CD populations.Disease phenotype according to the Montreal classification and long-term disease course was analysed according to the age at onset in time-dependent univariate and multivariate analysis.RESULTS:Among this population-based cohort,seventy-four(12.8%) pediatric-onset CD patients were identified(diagnosed ≤ 17 years of age).There was no significant difference in the distribution of disease behavior between pediatric(B1:62%,B2:15%,B3:23%) and adult-onset CD patients(B1:56%,B2:21%,B3:23%) at diagnosis,or during follow-up.Overall,the probability of developing complicated disease behaviour was 49.7% and 61.3% in the pediatric and 55.1% and 62.4% in the adult onset patients after 5-and 10-years of follow-up.Similarly,time to change in disease behaviour from non stricturing,non penetrating(B1) to complicated,stricturing or penetrating(B2/B3) disease was not significantly different between pediatric and adult onset CD in a Kaplan-Meier analysis.Calendar year of diagnosis(P = 0.04),ileal location(P < 0.001),perianal disease(P < 0.001),smoking(P = 0.038) and need for steroids(P < 0.001) were associated with presence of,or progression to,complicated disease behavior at diagnosis and during follow-up.A change in disease location was observed in 8.9% of patients and it was associated with smoking status(P = 0.01),but not with age at diagnosis.CONCLUSION:Long-term evolution of disease behavior was not different in pediatric-and adult-onset CD patients in this population-based cohort but was associated to location,perianal disease and smoking status.