Epidemiology of Crohn's Disease.

Although our current understanding is limited, epidemiologic investigation of Crohn's disease holds great promise. Certain aspects of the epidemiology are clear. The incidence of Crohn's disease, which has increased over the past few decades, may have reached a plateau. The disease has its peak onset in early life, with a second peak among the elderly. It is more common in the developed countries and among Jews. Whether the disease is related to occupation, social class, marital status, stress, infection, diet, smoking, and oral contraceptives is less certain. This paper reviews the epidemiology of Crohn's disease and proposes areas in which further research is needed.