A study of constipation and related factors was carried out in 439 geriatric hospital patients, 183 people living in two old people's homes, and 78 patients visiting a geriatric day hospital. In addition, a cross-sectional survey of constipation and related factors was undertaken in 138 people older than 74 years and 74 people aged 41 to 50 years living at home. Constipation and the use of laxatives were most frequent in the geriatric hospital (79% and 76% respectively), followed by the old people's homes (59% and 60%), the day hospital (29% and 31%), elderly living at home (38% and 20%) and middle-aged living at home (12% and 5%). The results suggest an increased risk of constipation for the persons walking less than 0.5 km daily [relative risk (RR) = 1.7], walking with help (RR = 3.4), chairbound (RR = 6.9) and bedbound (RR = 15.9). The relative risk of constipation increased for the persons living in the old people's homes (RR = 1.7) and the geriatric hospital (RR = 2.2), and also with advancing age (between 75 and 84 years, RR = 2.9; over 84 years, RR = 4.9). The prevalence of constipation was directly correlated to fecal and urinary incontinence.