Although there is more that we need to learn more about the etiology of IBS, this should not keep us from providing nearly half of our patients with optimal care. Clinical guidelines set high standards for the diagnosis and treatment of IBS. This review aims to provide gastroenterologists with an update on some key elements and challenges.
IBS is the most common gastrointestinal disorder in the population, both in primary care and in specialist health care. Although not all patients will consult for IBS and most consulters are handled by family practitioners, patients with IBS constitute 30–50% of the workload at gastroenterology outpatient clinics [1]. The subset who are referred to gastroenterologists represents only the “tip of the iceberg” of IBS, characterized by more pronounced symptom intensity and higher levels of psychosocial problems than patients in primary care [2]. IBS is also associated with a markedly reduced quality of life and high utilization of health-care resources [1,3].
Irritable bowel syndrome (IBS) is an enigma. The Rome III Committee defines IBS as a functional gastrointestinal disorder: symptoms of IBS represent the clinical product of altered gut physiology and psychosocial factors interacting via the brain–gut axis. Research on IBS is flourishing, with the annual number of publications in PubMed exceeding 500 in 2005. In particular, research on the basic pathophysiological mechanisms involved and on drugs targeted towards the gastrointestinal tract is receiving significant attention. Some experts believe IBS will turn out to represent a series of poorly understood organic diseases [4]. Others caution against this “organification” of IBS and find it unlikely that an altered gene or set of specific biological etiologies will explain a complex brain–gut disorder such as IBS [5]. One phenomenon to support this cautious approach is the “comorbidity” aspect of IBS: patients with IBS report other gastrointestinal symptoms (such as heartburn and dyspepsia), somatic symptoms (such as musculoskeletal pain and headache), and psychiatric symptoms (anxiety and depression) more often than those without IBS [6,7]. Referred patients have the highest levels of comorbid symptoms and disorders. In contrast to the Rome III report, recent evidence shows that somatic and psychiatric comorbidity is a feature of IBS and not only of those with the condition who consult physicians [7]. The etiological implications of the observed comorbidity need further elucidation. The comorbidity of IBS also explains a large part of the reduced quality of life and increased use of health resources hitherto attributed to IBS [1,7]. Optimal care for patients with IBS will therefore often require physicians to look beyond the gastrointestinal tract. The comorbidity of IBS underlines the need for continuous and optimal care to be delivered to these patients by family practitioners. This report will focus on what gastroenterologists can do in clinical encounters with referred patients.
In the absence of a biological marker, diagnosing IBS continues to be a challenge. Nevertheless, all guidelines recommend that IBS can and should be made as a positive, symptom-based diagnosis [8,9]. This approach requires a careful interpretation of the temporal relationship between abdominal pain/discomfort, bowel habit, and stool characteristics. Diagnostic criteria have been established to facilitate a symptom-based diagnosis, with the Rome III criteria for IBS representing the latest revision (Table 1). The new criteria only feature minor changes from the Rome II list, including a simplified time frame and a subtype classification based on stool consistency. These criteria and a novel diagnostic questionnaire developed by a validation process can easily be downloaded from www.romecriteria.org. As acknowledged by the authors, the criteria are imperfect and there is a great need to generate data that will sharpen the criteria and validate their use in clinical practice. Interestingly, few if any studies have looked at how such criteria should be used in busy clinical practices [10,11]. However, the success of a positive diagnosis probably relies more on gastroenterologists’ attitudes and knowledge than on the strict use of criteria.
The positive symptom-based approach is preferred because it allows explanation, reassurance and education of the patient and reduces the need for costly and potentially harmful diagnostic evaluations [9,12]. Indeed, a confident diagnosis may be the physician’s most important therapeutic tool and is considered a cornerstone in the general treatment approach (see below). Importantly, although this approach differs from a traditional “diagnosis of exclusion” approach, it does not rule out the need for additional investigations before a diagnosis of IBS is reached in every patient.
In a harmless disorder such as IBS, symptoms may range from negligible to incapacitating. In the absence of curative treatment, symptomatic and supportive treatment is the goal. The guidelines recommend a graded general treatment approach, key elements of which are a strong physician–patient relationship, assessment of psychosocial factors, and targeted treatment in selected patients [8,9].
The establishment of a strong and therapeutic patient–physician relationship hinges on thorough evaluation and on reassurance and education of the patient. The patient-physician encounter in IBS is challenging and can be frustrating to both parties. As the guidelines in Table 2 show, a structured approach is therefore recommended for establishing a therapeutic relationship. A quick look at these guidelines shows that gastroenterologists need to invest both time and interest. A therapeutic relationship will facilitate the assessment of psychosocial factors, which should include symptoms of depression and anxiety, somatic comorbid symptoms, health beliefs, coping, illness impact, and healthrelated quality of life. Another important dimension is the exploration of chronological “coincidences” between psychosocial factors and periods of worsening or improving symptoms. In patients with severe symptomatology, referral to a skilled psychiatrist or psychologist can be useful. Rome III suggests “red flags” for consideration of early referral to a mental health care provider. In addition to severe depression, some other red-flag items include chronic refractory pain, severe disability, and difficulties in physician–patient interaction.
Patient education is facilitated by written materials, which can be effective interventions in themselves. In patients with IBS in the United Kingdom, a selfhelp handbook reduced the use of health care and of perceived symptom severity [13]. We should make such handbooks available to our patients. In my experience, patients warmly welcome detailed information, and such books reduce my workload. Some of these books can also be recommended for physicians. I have learnt a lot from reading Nicholas Talley’s Conquering Irritable Bowel Syndrome [14].
Whereas patients with mild symptoms are likely to benefit from the above general treatment approach, patients with more severe symptoms will often need targeted treatment for their most troublesome symptoms. A detailed review of such treatment is beyond the scope of this report. In general, drugs help only some symptoms in selected patients, and there is a notable placebo effect. Novel drug treatments such as serotoninreceptor agonists and antagonists display have been disappointing, and they are unavailable in most European countries. While we are waiting for more effective drugs for IBS, gastroenterologists need to provide patients with proven effective drug treatment. Such treatment includes tricyclic antidepressants in low doses for abdominal pain, loperamide for diarrhea/urgency, and soluble fiber for constipation [15–18].
Mind–body treatment (psychological intervention) is also effective in IBS, although there is a shortage of highquality evidence [16]. Treatment modalities include gut-focused hypnotherapy, cognitive behavioral therapy (CBT), stress relaxation therapy, and interpersonal therapy. In particular, hypnotherapy and CBT have demonstrated beneficial effects in severely affected patients in clinical trials [19]. The advantages of mind–body treatment include efficacy in relation to comorbid conditions in IBS, its absence of adverse effects, and the shift of the locus of control so that patients themselves may feel more able to cope with the symptoms. If the goal is global improvement of patients’ lives and reduction of health-resource use, then mind–body treatment should more often be the treatment of choice. A major challenge is that such treatment is resource-demanding and that it requires highly skilled therapists interested in IBS. In my experience, these therapists are not easy to find.
The recommendations for the diagnosis and treatment of patients with IBS made by Rome III are by no means revolutionary [20,21]. One would therefore expect these recommendations to be widely implemented in clinical practice. Unfortunately, evidence suggests that this is not the case and that we have a long way to go.
We need to improve physicians’ knowledge and attitudes towards functional gastrointestinal disorders. Many gastroenterologists still view functional gastrointestinal disorders as psychological disorders, or merely as an absence of organic disease, while others deny the existence of functional gastrointestinal disorders. Gastroenterologists often ascribe pejorative characteristics to the patient or show negative attitudes during patient encounters [8]. Rome III strongly advocates proper education of physicians, stating that functional gastrointestinal disorders should be prominent parts of undergraduate and postgraduate medical curricula, clinical training programs, and international symposia. There is probably a significant gap between these recommendations and current educational efforts in gastroenterology worldwide. As a hospital physician, I knew next to nothing about IBS before I became involved in IBS research.
We need to organize our clinical practice to set the scene for optimal diagnosis and treatment. Gastroenterology outpatient practice probably varies across countries all over the world. In Norway, gastroenterologists most often choose to perform a colonoscopy in these patients, based on a short referral note from the family practitioner. Accordingly, patients’ first (and perhaps only) clinical encounter with a gastroenterologist is when they are lying on the endoscopy table with their bowels emptied and anus facing the gastroenterologist. This is not the optimal setting for making a positive diagnosis and providing a general treatment approach! In addition, drugs administered before the endoscopic examination may affect patients’ memory and further diminish the value of a clinical consultation, which sometimes follows after the colonoscopy. Many gastroenterologists are strong believers in the therapeutic value of a colonoscopy with negative findings, but this belief is not supported by research evidence. In other words, it seems obvious that we need to reorganize practice if we are aiming to provide patients with the optimal care outlined above. Perhaps we should start with a well-conducted clinical consultation in patients with symptoms suggestive of IBS. In harmony with the principles of evidence-based health care, this approach would allow clinical expertise to be combined with patients’ preferences in the diagnostic evaluation. In a young patient with typical symptoms of IBS, a fecal calprotectin test might be sufficient to rule out inflammatory bowel disease [22]. Although some patients would need to come back for a colonoscopy, it is likely that a significant proportion of colonoscopies would be avoided. Gastroenterologists will, quite understandably, fear missed organic disease and an increased workload with this approach. We therefore need high-quality research evidence that this approach is reliable in terms of diagnostic validity and cost-effective in terms of relevant patient outcomes and health-resource usage. Although all existing evidence supports an approach based on a positive diagnosis and general treatment, there is urgent need for clinical research to improve the evidence base.
In conclusion, gastroenterologists face significant challenges in the clinical management of patients with IBS. The road from best evidence to best practice is seldom straightforward and involves many factors other than drawing up guidelines. For gastroenterologists, the first and crucial step on this road is to recognize that a confident diagnosis and a graded general treatment approach could be the best treatment we currently have to offer for many of our patients with IBS.