Fine-scale geographic variations of inflammatory bowel disease in France: correlation with socioeconomic and house equipment variables.

Background: In a previous study we found a north-south gradient for Crohn's disease (CD) incidence in France. The aim of the present study was to determine if socioeconomic factors may influence the geographic distribution of CD and ulcerative colitis (UC) in France.

Methods: Using the national health insurance databases, incidence rates of CD and UC were estimated for each of 341 metropolitan "job areas" in 2000-2002.