The incidence of inflammatory bowel disease (IBD) is increasing in Eastern Europe.
The reasons for these changes remain unknown.
Dr Burisch and colleagues from Denmark investigated whether an East–West gradient in the incidence of IBD in Europe exists.
A prospective, uniformly diagnosed, population based inception cohort of IBD patients in 31 centres from 14 Western, and 8 Eastern European countries covering a total background population of approximately 10.1 million people was created.
One-third of the centers had previous experience with inception cohorts.
|35% were diagnosed with Crohn's disease|
Patients were entered into a low cost, web based epidemiological database, making participation possible regardless of socioeconomic status and prior experience.
The research team evaluated 1515 patients aged 15 years or older, of whom 35% were diagnosed with Crohn's disease, 54% with ulcerative colitis, and 11% with IBD unclassified (IBDU).
The team observed that the overall incidence rate ratios in all Western European centres were 1.9 for Crohn's disease, and 2.1 for ulcerative colitis compared with Eastern European centers.
The median crude annual incidence rates per 100,000 in 2010 for Crohn's disease were 7 in Western European centers, and 3 in Eastern European centers, for ulcerative colitis 11 and 4, respectively, and for IBDU 2 and 0, respectively.
In Western Europe, 92% of Crohn's disease, 78% of ulcerative colitis, and 74% of IBDU patients had a colonoscopy performed as the diagnostic procedure compared with 90%, 100% and 96%, respectively, in Eastern Europe.
The researchers found that 8% of Crohn's disease, and 1% of ulcerative colitis patients in both regions underwent surgery within the first 3 months of the onset of disease.
The team noted that 7% of Crohn's disease patients, and 3% of ulcerative colitis patients from Western Europe received biological treatment as rescue therapy.
Of all European Crohn's disease patients, 20% received only 5-aminosalicylates as induction therapy.
Dr Burisch's team comments, "An East–West gradient in IBD incidence exists in Europe."
"Among this inception cohort—including indolent and aggressive cases—international guidelines for diagnosis and initial treatment are not being followed uniformly by physicians."