Romanian National Study on the Epidemiology of Inflammatory Bowel Diseases

Inflammatory bowel diseases (IBD), including Crohn's disease (CD), ulcerative colitis (UC), and IBD-unclassified (IBD-U), are increasingly recognized across Eastern Europe, including Romania, where historical data indicated low incidence. Contemporary real-time epidemiological data for our country are scarce. This study evaluated the short-term frequency and epidemiological characteristics of IBD patients presenting to major Romanian gastroenterology centers.

We conducted a prospective, cross-sectional observational study over a 14-day period in November 2024 across 18 university-affiliated tertiary gastroenterology clinical sites in Romania. All consecutive adult patients with confirmed IBD were enrolled using a centralized online platform. Demographics, disease type and phenotype, severity, and treatment were recorded and analyzed descriptively.

A total of 1,045 patients were registered: 52.4% CD, 46.9% UC, and 0.7% IBD-U. Geographical distribution revealed a statistically significant variation, with Crohn's disease being more frequent in Southern Romania, while UC predominated in the Eastern and Central-western regions (p=0.0009). Most patients resided in urban areas, and the majority were in clinical remission at presentation. Phenotypic analysis revealed ileocolonic CD (L3) and left-sided/pancolitis UC (E2/E3) as most frequent. Severe disease history was more common in CD, and prior surgery was significantly higher in CD than UC. Smoking and appendectomy were more frequently associated with CD as previously reported. Therapeutic patterns reflected disease type: anti-TNF use predominated in CD, while other biologics and small molecules were more common in UC. Regional differences in therapy were observed, with southern centers showing higher use of novel therapies, likely reflecting a more mature IBD population, with a higher CD prevalence. Notably, the number of IBD diagnoses increased over time, correlating with Romania's GDP growth (R² = 0.89, p < 0.001), suggesting that socioeconomic factors may influence disease recognition and diagnosis.

This study offers the most recent snapshot of IBD epidemiology in Romania, highlighting a transition toward medium-incidence patterns and growing clinical complexity. These findings provide evidence for the need to establish nationwide population-based surveillance systems and healthcare planning initiatives aimed at mitigating the rising burden of IBD.