People with ulcerative colitis may be suffering from repressed anger, but their psychological state has nothing to do with the cause of their gastrointestinal illness, researchers contend.

Since 1930, more than 100 studies have purported to show that the painful and potentially fatal disorder in which the inner linings of the colon and rectum become full of bleeding sores and abscesses was caused by psychological factors.

In a review of all of these studies published in the August issue of the American Journal of Psychiatry, a psychiatrist and two gastroenterologists from Washington University School of Medicine in St. Louis, found that most were so seriously flawed as to be useless. In addition, they concluded that "examination of the results of the seven best studies revealed that significant psychopathology and prior life events are found in patients with ulcerative colitis no more often" than in healthy subjects.

Carol North, a psychiatrist and chief author of the study, wrote that "it is inviting to invoke a psychological explanation" in illnesses where no specific cause can be found, as is the case for ulcerative colitis. Doctors now recognize that most illnesses have a psychosomatic component, meaning that there is a link between mind and body but no causal connection.

But, she continued, "there is no evidence that ulcerative colitis is in any way a special disease in its relation to stress." Treatment based largely on the old psychosomatic model -- that disease is caused by emotions -- "would be a disservice" to the 2 million Amercians who have inflammatory bowel disease, which includes ulcerative colitis.