Digestive disorders

II/4.2: Epidemiology

It is the fifth most important gastrointestinal disease in the Western countries. It is a disease of civilization; it is common in industrially developed countries (Europe, North America, Australia), while it is rare among folks of nature (Africa, Asia). It usually causes no symptoms and therefore no exact incidence is known. Its incidence has risen from 5 to 10% observed in the 1920s to 35 to 50% nowadays. It is more frequent (30 to 40%) in the developed countries, and it is less frequent (1 to 4%) in the developing countries. Its incidence increases with the age; it is 5% in people under 40 years and 50 to 65% in people older than 80 years. It is less frequent among vegetarians. Usually it is equally frequent in females and males; however the complicated disease is particularly more common in obese males under 50 years (84 to 96%), while there are more female patients among the elderly.