Evolution of Clinical Behavior in Crohn's Disease: Factors Associated with Complicated Disease and Surgery.

BACKGROUND: The phenotypic expression of Crohn's disease may vary over time. Establishment of Crohn's disease phenotypes is important for definition of patient care strategies.

AIMS: The aim of the study was to evaluate the long-term evolution of patients based on disease phenotypes and the main factors associated with this evolution.

METHODS: Data from 179 patients were collected from a unicentric prospective database. Montreal classification was employed. Kaplan-Meier method was used to estimate the cumulative probability of complication development and surgery. Poisson regression for multivariate analysis was applied. The Local Institutional Review Board approved the research.

RESULTS: Female: 54.2%. Mean age at diagnosis: 32.7 (±13.7) years. Behavior at presentation: inflammatory 62.0%, stricturing 24.6%, penetrating 13.4%; perianal disease: 31.8%; median follow-up time: 65.2 months (IQR 31.0-108.8). Behavior at follow-up period end: inflammatory 43.6%, stricturing 38.0%, penetrating 18.4%; perianal disease: 46.4%. Cumulative probability of being complication free in 5, 10, and 20 years: 86.3, 66.4, and 52.2%, respectively. Cumulative probability of being surgery free in 5, 10, and 20 years: 87.3, 79.2, and 64.1%, respectively. L1 and L4 locations, use of immunosuppressive therapy, smoking, number of hospitalization/patient-year, abdominal surgery, age at diagnosis <40 years, and biological therapy were the factors associated with changes in phenotype or development of complications and perianal disease.

CONCLUSION: Clinical behavior altered in about one-third of patients. The most frequent complication was a change to stricturing pattern. Disease location, current smoker, immunosuppressive therapy use, hospitalization, and abdominal surgery were factors associated with an unfavorable clinical evolution.