Authors: Wilson S, Roberts L, Roalfe A, Bridge P, Singh S.

Institution: Department of Primary Care and General Practice, University of Birmingham, Edgbaston. s.wilson@bham.ac.uk

Background: Irritable bowel syndrome (IBS) is a common health problem affecting a substantial proportion of the population. Many individuals with symptoms of IBS do not seek medical attention or have stopped consulting because of disillusionment with current treatment options. Such patients may choose to re-consult with the advent of new therapies with a resulting impact on health services. AIM: To generate reliable estimates of the prevalence of IBS by age, sex and symptom group.

Conclusion: Quality of life was significantly reduced in patients with IBS. There is a substantial burden on primary healthcare services despite over half of those with symptoms also self- medicating. The Rome II diagnostic criteria identified those most affected by their symptoms and are a valid clinical tool. Population-based health surveys will need to supplement the Rome criteria with questions aiming to identify patients formally diagnosed but whose symptoms are currently under control if prevalence is to be reliably estimated.

Study link: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15239910&query_hl=33&itool=pubmed_docsum

Authors: Hu WH, Wong WM, Lam CL, Lam KF, Hui WM, Lai KC, Xia HX, Lam SK, Wong BC.

Institution: Department of Medicine, University of Hong Kong, China.

Aims: To study the prevalence of dyspepsia and irritable bowel syndrome and the effects of co-existing anxiety and depression on health care utilization by a population survey in Chinese.

Results: One thousand, six hundred and forty-nine subjects completed the interview (response rate, 62%). The population prevalences of dyspepsia, irritable bowel syndrome and gastro-oesophageal reflux disease were 18.4%, 4.1% and 4.8%, respectively. Dyspepsia and irritable bowel syndrome were associated with anxiety, depression, medical consultation, sick leave and adverse effects on social life. The degree of anxiety was an independent factor associated with health care-seeking behaviour in both dyspeptics (P = 0.003) and irritable bowel syndrome patients (P = 0.036).

Conclusions: Irritable bowel syndrome and dyspepsia are associated with anxiety, depression, significant social morbidity, health care utilization and days off work. Anxiety is an independent factor in determining health care utilization in patients with dyspepsia and irritable bowel syndrome.

Study link: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12452941&query_hl=39&itool=pubmed_docsum

Author: Lydiard RB.

Institution: Mood and Anxiety Program, Medical University of South Carolina, Charleston 29425, USA.

Summary: Irritable bowel syndrome (IBS) is a common and potentially disabling functional gastrointestinal disorder characterized by abdominal pain and altered bowel patterns. A significant amount of clinical and research data suggest the importance of the brain-gut interaction in IBS.

This review examines the observed high prevalence of psychiatric disorders in patients with IBS. The published literature indicates that fewer than half of individuals with IBS seek treatment for it. Of those who do, 50% to 90% have psychiatric disorders, including panic disorder, generalized anxiety disorder, social phobia, posttraumatic stress disorder, and major depression, while those who do not seek treatment tend to be psychologically normal.

Both physiologic and psychosocial variables appear to play important roles in the development and maintenance of IBS. Recent information suggests that the association of IBS and psychiatric disorders may be more fundamental than was previously believed. A brain-gut model for IBS is presented, and the role of traumatic stress and corticotropin-releasing factor as modulators of the brain-gut loop is discussed. Finally, the rationale for the use of psychotropic agents in the treatment of IBS with or without psychiatric symptoms is presented.

Study link: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=12108820&query_hl=35&itool=pubmed_docsum

Authors: Lackner JM, Quigley BM, Blanchard EB.

Institution: Department of Medicine, University at Buffalo School of Medicine and Biomedical Sciences, State University of New York, Buffalo, NY 14215, USA. lackner@buffalo.edu

Objective: Depression has been linked to irritable bowel syndrome (IBS), but the mechanism underlying this relationship is unknown. This cross-sectional study explores the possibility that negatively skewed beliefs patients hold regarding abdominal pain (ie, catastrophizing) mediate the relationship between depression and pain severity.

Results: Using a mediational model involving a series of linear regressions, results indicated that pain catastrophizing partially mediated the link between depression and abdominal pain severity. Depression, catastrophizing, and control variables accounted for 21% of the variance in pain severity. The finding that patients with IBS with greater depression reported greater pain severity can be partially explained by their tendency to engage in more catastrophic thinking specific to pain.

Conclusions: The relation between depression and pain is not, as psychogenic models predict, strictly a direct and linear one but works partly through patients' beliefs regarding their pain in general and pain catastrophizing in specific. Implications of the findings for understanding and investigating the depression-IBS link from a biopsychosocial perspective are discussed.

Study link: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=15184708&query_hl=17&itool=pubmed_DocSum

Authors: Olafsdottir LB, Gudjonsson H, Thjodleifsson B.

Institution: Iceland University Hospital, Hringbraut, 101 Reykjavik, Iceland. bjarnit@landspitali.is

Objective: The aim of the present study was to evaluate the prevalence of functional bowel disorders (FBD) in a population-based sample and to assess FBD-related health care seeking and medication in Iceland.

Results: …Both symptom categories were more common in women and the prevalence decreased with age. No correlation with socioeconomic status was found. There was more than 90% overlap between the two diagnostic categories. Irritable bowel syndrome was found to be associated with depression, appendectomy and dysmenorrhea.

Conclusions: This population-based study shows a high prevalence of functional bowel disorders in Iceland and higher than reported in other studies that use similar criteria. It can be speculated that the reasons for this high prevalence are associated with special features of the socio-psychological profile of the Icelandic society.

Study link: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=16155326&query_hl=7&itool=pubmed_docsum