The aim of the study was to assess (1) the prevalence of colon related
symptoms among the elderly and (2) whether different definitions iden
tify different subjects with Irritable Bowel Syndrome. The study was c
arried out in a random sample of 1119 70-year-old Danes of whom 72% an
swered a questionnaire concerning colon related symptoms. The number o
f bowel movements a week ranged from 0 to 21 among men and 1 to 28 amo
ng women, 5% limits were at < 3 or > 15 movements a week. The individu
al symptoms occurred with prevalences between 16 and 25% among men and
27 and 41% among the women. Abdominal pain, distension and borborygmi
occurred significantly more often among women than men, whereas no se
x difference was found for alternating stool consistency and number of
bowel movements. According to the different definitions the prevalenc
e of Irritable Bowel Syndrome varied from 0 to 18% among men and 4 to
32% among women. The subpopulations with Irritable Bowel Syndrome iden
tified by various definitions had less than half of the subjects in co
mmon.