[Constipation--a risk factor for colorectal cancer]

A new, chronophysiological, conception of constipation is based upon the fundamental principle of the circadian regularity of the bowel evacuatory function. The slowing of the near-day (24 +/- 4 hours) regularity of this function in a form of intestinal bradiarrhythmia is an attribute of constipation. According to epidemiological and endoscopic data, constipation, as the basis of colorectal coprostasis, is one of the main risk factors of colorectal cancer (CRC). The morphological signs of large bowel pre-cancer (dysplasia, adenomatosis, polyposis) seem to be secondary to the primary functional disorder of the circadian rhythm. In Saint Petersburg there are no statistics on the diagnostics of constipation, but CRC occupies the leading position in the structure of total oncological morbidity and female oncological mortality (the so called "Petersburg paradox"). Colorectal bradiarrhythmia, which precedes constipation, is the earliest functional (prenosological) CRC risk factor.