Cumulative disease-course phenotypes in Crohn's disease: a retrospective single center FAMD clustering study

The study analyzed 98 patients with Crohn's disease using factor analysis of mixed data (FAMD) to identify three distinct disease-course phenotypes. The research included clinical, treatment, surgical, and comorbidity variables. Three clusters were identified: C1 (56 patients), C2 (31 patients), and C3 (11 patients). The C3 group was characterized by younger age at diagnosis, higher burden of extra-intestinal manifestations, more intensive treatment, greater biologic therapy exposure, and higher number of surgical procedures. Montreal behavior and comorbidity burden were the strongest predictors of C3 group membership. A model based on variables available at diagnosis (age, disease location, and Montreal behavior) achieved moderate discrimination for the C3 group (AUC=0.80). The results suggest that disease-course phenotypes identified using FAMD clustering are clinically interpretable and stable.