While medical students can confidently hold forth on the mechanisms of the Zollinger-Ellison syndrome, a condition affecting one in a million of the population, they rarely have much to say about functional GI disorders (FGIDs), which can affect up to a quarter of the population at some stage in their life. Part of the reason is that this is a complex area, which requires the integration of pathophysiology with psychology, and even sociology. FGIDs also suffer from having no objective measurable abnormalities, so that classifications must of necessity be symptom based. The Rome process is a valiant attempt to make this area of study less confused, more consistent, and scientifically respectable. As such, it undoubtedly has had a major impact, and Rome criteria are now used for the entry into most clinical trials and studies in this area. The senior chairman claims that this process has "done for functional gastrointestinal disorders what the Diagnostic and Statistical Manual of Mental Disorders (DSM-IIII) has done for psychiatry". While this may appear grandiose, I think it just might be true.
This book provides an overview of many years' work, which have seen major advances in our understanding of functional gastrointestinal disease (FGID). This is due in no small part to the "Rome" process, which is described in detail in the book. The challenge was to create order out of chaos by agreeing criteria for the diagnosis of FGIDs. The major advantage of such a classification is that studies using agreed definitions become comparable and the next study can build on the results of the last. The major disadvantages, which the authors constantly remind the reader of, are that uncritical readers may accept these definitions as fixed in stone. This would of course stultify inquiry and progress. We need to be constantly reminded that the new Rome criteria (for example, for irritable bowel syndrome), in reality excludes as many as 60% of the patients diagnosed as having IBS in clinical practice. This has the advantage of producing closely comparable patients for studies, but the disadvantage of reduced generalisability to normal clinical practice.
The excellent introductory chapter outlines the ideas behind the Rome process and emphasises the importance of the "bio-psycho-social model for IBS" for understanding how sufferers become patients. I much enjoyed the next chapter on the basic science for neurogastroenterology, which simplifies much work and renders it in a form readily understandable to clinicians with only vague memories of neuroanatomy. There then follows a section on motility and sensation measurements, again comprehensive but suitably cautious. There are sections on psychological assessments, and a good account of the weaknesses and strengths of various psychological rating scales for the non-psychiatrist. Specific functional disorders are then dealt with by distinguished coauthors and, as would be expected, these chapters form a comprehensive, well referenced account of current understanding of these conditions. There is also a detailed account of how the new criteria differ from the old ones, and what evidence has been used to make these changes. One disappointment for me, was to see how sparse the new evidence was and what a long way there is to go before we understand the pathophysiology of most of these conditions. One example of the dangers of classification, if it replaces true inquiry, is the lack of any mention in the definition of irritable bowel syndrome of the response to food. Exaggerated defecation after eating and remission of abdominal pain on fasting is a very common feature in IBS, and yet it is not part of the definition. The danger is that this will lead the response to food to be ignored and not subject to the same detailed study as it might otherwise justify.
Although reviews are meant to be critical, I do believe that this book is essential reading for gastroenterologists, particularly those entering research in the important field of functional gastrointestinal diseases. There is a useful chapter on the design of treatment trials and appendices including some sample questionnaire forms that would be useful to examine before setting up a study. My main caveat is to ensure that readers do listen carefully to the words of wisdom of W G Thompson, who clearly states that this document "does not represent the end but rather the end of the beginning". It is important to test these criteria and to alter them as new evidence accumulates on the underlying mechanisms. They are a vital staging post in the route to increased understanding, however the more we understand mechanisms, the less important these symptom based definitions will become. Once the importance of hypertension was recognised and effective treatment became available, we no longer focused on symptoms such as headaches and blurred vision, but simply measured the blood pressure. It seems likely that the Rome process has the seeds of its own destruction inbuilt, but, given the enormity of the problem, not any time soon!
Robin Spiller, MD
University Hospital
Nottingham, UK
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