Incidence varies significantly by region, with about 5,000 to 10,000 new cases per year in the United States. The disease is most common in North America, Europe and Scandinavia, and the incidence is greater in urban and northern environments. Medical therapy is the primary approach to treatment. Since surgery is generally not curative, surgery is reserved for use only when medical therapy is inadequate. Medical therapies have remained relatively unchanged for decades, with only recent introductions of novel delivery formulations and analogs of older drugs.
Mainstay drugs are corticosteroids, aminoosalicylates and immunomodulatory drugs.
Steroids have significant side effects, including mood changes, exacerbation of hypertension and diabetes, increased appetite and weight gain, and sleep disorders. Chronic use can result in osteoporosis, immune suppression, cataracts and serious endocrinological changes. Most patients will achieve repeated remissions of varying lengths with medical therapy. About 70 percent will require surgery in their lifetimes, with about 55 percent within 10 years of diagnosis. In a national survey, published in 1994, it was reported that 700,000 office visits were for inflammatory bowel disease.