Review Identifies Misconceptions about Constipation and Its Treatment Showing Popular Beliefs Are Not Based on Evidence.

BERLIN, Germany -- Independent Review of Available Evidence for Popular Beliefs on Constipation Published Today

Results from an extensive, independent review into existing evidence

on chronic constipation and the treatment thereof are published today in the American Journal of Gastroenterology showing that many of the popular and strongly held beliefs surrounding this disorder are not evidence based.

The review was undertaken by four leading experts, from Europe and the US, in the field of gastroenterology and the results of their findings are presented in the 'Myths and Misconceptions About Chronic Constipation' paper. The purpose of the review, conducted over a five-month period, was to examine all documentation and available evidence of widely held beliefs, some of which originate even from the 16th century B.C., concerning various aspects of constipation and the quality of evidence used to support these beliefs. These concepts encompass pathophysiology and treatment of constipation, all of which are widely held in both the medical and lay communities.

Professor Muller-Lissner, Germany, lead author of the paper on behalf of his co-authors, Professors Wald, US, Kamm, UK and Scarpignato, Italy comments, "We are delighted to be able to present these findings to both the medical community and more importantly to constipation sufferers who have been misled into thinking that they are the major cause of, and especially to blame for, the symptoms of this sensitive disorder. We hope that in publishing this paper, we can move medical thinking forward to accept the realities of this condition and accordingly recommend appropriate treatments rather than exacerbate symptoms and sufferers' fears by providing mis-information."

Key findings reported in the paper are as follows:

Lack of dietary fibre has often been championed as a cause of constipation, with fibre supplements being readily recommended to help relieve symptoms. The authors conclusively agree that a diet poor in fibre should not be assumed to be the cause of chronic constipation. In fact, they found that while several groups of patients may be helped by a fibre-rich diet, those with severe constipation actually develop worsening symptoms when increasing dietary fibre intake.

Increase in fluid intake is also a long-held myth associated with providing relief from constipation and again the paper found no evidence to support this claim. The authors believe this misconception is derived from observations that comparatively small changes to the water content of stools lead to considerable changes of consistency which are thought to be related to the total water intake. However, these small changes are insignificant in comparison to the total amount of fluid exchanges taking place in the intestinal tract. Various studies examining variances in fluid intake in both healthy subjects and those who were constipated concluded that there is no evidence that constipation can be successfully treated by increasing fluid intake, unless there is evidence of dehydration.

Reduction in physical activity has been linked to increased symptoms of constipation and the paper concludes that it is indeed relevant in elderly sufferers. However, these findings need to be put in context with other likely cofactors, such as medications, diet and personality. Intervention programmes to increase physical activity may help to improve symptoms, but these are less effective in young, severely constipated sufferers.

Much unfounded controversy has been generated over the years regarding laxative-use in treating constipation, resulting in unnecessary fears relating to proactive use/recommendation by both consumers and healthcare professionals. The paper discusses these misconceptions:

--Damage to the colon: Claims that laxatives cause damage to the colon are not supported and the findings highlight that these claims have been based on poorly documented experiments

--Colorectal cancer: There are no data to support the claim that stimulant laxatives are an independent risk factor

--Electrolyte disturbance: Any theoretically possible electrolyte disturbance by stimulant laxative use can be minimised with appropriate drug and dose selection

--Tolerance to stimulant laxatives: Tolerance is shown to be uncommon in the majority of users and found to occur only in the most severe patient group

--Rebound constipation: There is no evidence for the occurrence of rebound constipation after stopping laxatives

--Addiction: There is no potential for addiction to laxatives, although they may be misused by psychiatric patients

In conclusion, the paper recognises that the use of stimulant laxatives in the management of constipation symptoms is safe.

Sex hormones are also incorrectly believed to play a key role in causing constipation. This is based on the observation that constipation is more common in boys but between the ages of 15-50 it is more prevalent in women. Furthermore, women also report changes in bowel function during different stages in their menstrual cycles. Having reviewed the evidence, the paper found that sex hormones only play a minimal role in otherwise healthy women, although they may play a role during pregnancy when the changes in hormone levels are much greater.

The paper also concluded that there is no evidence to support the outdated notions of:

--Autointoxication, an ill-conceived theory that has been long-since abandoned by the scientific community should have no place in clinical practice today.

--Dolichocolon, a term used for an elongated colon, has been implicated in the past as a cause of constipation but was shown to lack any supportive evidence.

Notes to Editors

For further information please visit the American Journal of Gastroenterology website, http://www.amjgastro.com or contact:

Prof. Stefan Muller-Lissner              Prof. Michael Kamm
Park-Klinik Weissensee                   St Mark's Hospital
Humboldt University                      Watford Road
Schoenstrasse 80                         Harrow
13086 Berlin                             HA1 3UJ
Germany                                  United Kingdom
Tel: [phone]                    Tel: [phone]
Mail: [e-mail]              Mail: [e-mail]

Prof. Carmelo Scarpignato                Prof. Arnold Wald
School of Medicine & Dentistry           University of Pittsburgh
University of Parma                      Division of Gastroenterology
Via Volturno 39                          Mezz Level, C Wing, PUH
43100 Parma                              200 Lothrop Street
Italy                                    Pittsburgh, PA 15213
Tel [phone]                      USA
Mail: [e-mail]                      Tel: [phone]
                                         Mail: [e-mail]

References

1. Muller-Lissner SA, Kamm MA, Scarpignato C, Wald A. Myths and Misconceptions About Chronic Constipation. American Journal of Gastroenterology 2005; www.amjgastro.com