Lower Bowel Symptoms Research Articles

Negative predictive value of fecal immunochemical testing in significant bowel disease screening: A systematic review and meta-analysis.

General practitioners (GPs) must assess significant bowel disease (SBD) in patients with lower bowel symptoms during primary care. Studies have evaluated the efficacy of fecal immunochemical testing (FIT) for SBD screening. However, the effectiveness of FIT remains controversial. This study aimed to investigate the value of FIT in SBD screening. PubMed, the Cochrane Database, and EMBASE were systematically searched. Studies that estimated FIT values in screening for SBD among patients with lower bowel symptoms were included. Sensitivity, specificity, negative likelihood ratio (NLR), positive likelihood ratio (PLR), diagnostic odds ratio (DOR), and negative predictive value (NPV) were calculated. Additionally, the pooled area under the summary receiver operating characteristic (SROC) curve was analyzed. A total of 8,615 patients with lower bowel symptoms who underwent FIT and colonoscopy to screen for SBD were enrolled and assessed in this meta-analysis; of these, 1,226 patients were ultimately diagnosed with SBD. The pooled sensitivity, specificity, PLR, NLR, DOR, and NPV of FIT in SBD screening were 0.65 (95% CI [confidence interval] 0.50-0.78), 0.85 (95% CI 0.72-0.92), 4.2 (95% CI 2.60-6.90), 0.41 (95% CI 0.29-0.58), 10 (95% CI 6-17), and 0.90 (95% CI 0.87-0.94), respectively. Besides, the pooled SROC was 0.82 (95% CI 0.78-0.85). This study indicates that the FIT provides a favorable NPV for SBD screening and could be a valuable technique for GPs to rule out SBD in primary care. At the same time, GPs need to remain vigilant and refer patients to gastroenterologists when necessary.

Robot-Assisted Sacrocolpopexy versus Trans-Vaginal Multicompartment Prolapse Repair: Impact on Lower Bowel Tract Function.

This study evaluated the effectiveness, safety, and possible changes in bowel symptoms after multicompartment prolapse surgery by comparing two different surgical approaches, transvaginal mesh surgery with levatorplasty (TVMLP) and robot-assisted sacrocolpopexy (RSC). All patients underwent pelvic (POP-Q staging system) and rectal examination to evaluate anal sphincter tone in the lithotomy position with the appropriate Valsalva test. The preoperative evaluation included urodynamics and pelvic magnetic resonance defecography. Patient Global Impression of Improvement (PGI-I) at follow-up measured subjective improvement. All patients completed Agachan-Wexner's questionnaire at 0 and 12 months of follow-up to evaluate bowel symptoms. A total of 73 cases were randomized into the RSC group (36 cases) and TVMLP group (37 cases). After surgery, the main POP-Q stage in both groups was stage I (RCS 80.5% vs. TVMLP 82%). There was a significant difference (p < 0.05) in postoperative anal sphincter tone: 35%. The TVMLP group experienced a hypertonic anal sphincter, while none of the RSC group did. Regarding subjective improvement, the median PGI-I was 1 in both groups. At 12 months of follow-up, both groups exhibited a significant improvement in bowel symptoms. RSC and TVMLP successfully corrected multicompartment POP. RSC showed a greater improvement in the total Agachan-Wexner score and lower bowel symptoms.

Predictive Value of Carcinoembryonic Antigen in Symptomatic Patients without Colorectal Cancer: A Post-Hoc Analysis within the COLONPREDICT Cohort.

We aimed to assess the risk of cancer in patients with abdominal symptoms after a complete colonoscopy without colorectal cancer (CRC), according to the carcinoembryonic antigen (CEA) concentration, as well as its diagnostic accuracy. For this purpose, we performed a post-hoc analysis within a cohort of 1431 patients from the COLONPREDICT study, prospectively designed to assess the fecal immunochemical test accuracy in detecting CRC. Over 36.5 ± 8.4 months, cancer was detected in 115 (8%) patients. Patients with CEA values higher than 3 ng/mL revealed an increased risk of cancer (HR 2.0, 95% CI 1.3–3.1), CRC (HR 4.4, 95% CI 1.1–17.7) and non-gastrointestinal cancer (HR 1.7, 95% CI 1.0–2.8). A new malignancy was detected in 51 (3.6%) patients during the first year and three variables were independently associated: anemia (OR 2.8, 95% CI 1.3–5.8), rectal bleeding (OR 0.3, 95% CI 0.1–0.7) and CEA level >3 ng/mL (OR 3.4, 95% CI 1.7–7.1). However, CEA was increased only in 31.8% (95% CI, 16.4–52.7%) and 50% (95% CI, 25.4–74.6%) of patients with and without anemia, respectively, who would be diagnosed with cancer during the first year of follow-up. On the basis of this information, CEA should not be used to assist in the triage of patients presenting with lower bowel symptoms who have recently been ruled out a CRC.

Appraisal of the faecal haemoglobin, age and sex test (FAST) score in assessment of patients with lower bowel symptoms: an observational study

BackgroundMany patients present in primary care with lower bowel symptoms, but significant bowel disease (SBD), comprising colorectal cancer (CRC), advanced adenoma (AA), or inflammatory bowel disease (IBD), is uncommon. Quantitative faecal immunochemical tests for haemoglobin (FIT), which examine faecal haemoglobin concentrations (f-Hb), assist in deciding who would benefit from colonoscopy. Incorporation of additional variables in an individual risk-score might improve this approach. We investigated if the published f-Hb, age and sex test score (FAST score) added value.MethodsData from the first year of routine use of FIT in primary care in one NHS Board in Scotland were examined: f-Hb was estimated using one HM-JACKarc FIT system (Kyowa Medex Co., Ltd., Tokyo, Japan) with a cut-off for positivity ≥10 μg Hb/g faeces. 5660 specimens were received for analysis in the first year. 4072 patients were referred to secondary care: 2881 (70.6%) of these had returned a FIT specimen. Of those referred, 1447 had colonoscopy data as well as the f-Hb result (group A): 2521 patients, also with f-Hb, were not immediately referred (group B). The FAST score was assessed in both groups.Results1196 (41.7%) of patients who returned a specimen for FIT analysis had f-Hb ≥10 μg Hb/g faeces. In group A, 252 of 296 (85.1%) with SBD had f-Hb > 10 μg Hb/g faeces, as did 528 of 1151 (45.8%) without SBD. Using a FAST score > 2.12, which gives high clinical sensitivity for CRC, only 1143 would have been referred for colonoscopy (21.0% reduction in demand): 286 of 296 (96.6%) with SBD had a positive FAST score, as did 857 of 1151 (74.5%) without SBD. However, one CRC, five AA and four IBD would have been missed. In group B, although 95.2% had f-Hb < 10 μg Hb/g faeces, 1371 (53.7%) had FAST score ≥ 2.12: clinical rationale led to only 122 of group B completing subsequent bowel investigations: a FAST score > 2.12 was found in 13 of 15 (86.7%) with SBD.ConclusionsThe performance characteristics of the FAST score did not seem to enhance the utility of f-Hb alone. Locally-derived formulae might confer desired benefits.

Do other variables add value to assessment of the risk of colorectal disease using faecal immunochemical tests for haemoglobin?

Background Faecal immunochemical tests for haemoglobin have been recommended to assist in assessment of patients presenting in primary care with lower bowel symptoms. The aim was to assess if, and which, additional variables might enhance this use of faecal immunochemical tests. Methods Faecal immunochemical test analysis has been a NHS Tayside investigation since December 2015. During the first year, 993 patients attending colonoscopy were invited to complete a detailed questionnaire on demographic background, symptoms, smoking status, alcohol use, dietary fibre, red and processed meat intake, physical activity, sitting time, dietary supplement use, family history of colorectal cancer, adenoma, inflammatory bowel disease and diabetes. Significant bowel disease was classified as colorectal cancer, advanced adenoma or inflammatory bowel disease. Results A total of 470 (47.3%) invitees agreed to complete the questionnaire and 408 (41.1%) did. Unadjusted odds ratios for the presence of significant bowel disease compared with undetectable faecal haemoglobin increased with increasing faecal haemoglobin and for faecal haemoglobin 10–49, 50–199, 200–399 and ⩾400 μg Hb/g faeces were 0.95 (95% CI: 0.16–5.63), 2.47 (0.55–1.03), 6.30 (1.08–36.65) and 18.90 (4.22–84.62), respectively. Rectal bleeding and family history of polyps were the only other variables with statistically significant ( P &lt; 0.05) odds ratios greater than 1.00, being 1.88 (1.13–3.17) and 2.93 (1.23–6.95), respectively. Odds ratios adjusted for all other variables showed similar associations, but only faecal haemoglobin and family history of polyps had significant associations. Conclusions Faecal haemoglobin is the most important factor to be considered when deciding which patients presenting in primary care with lower bowel symptoms would benefit most from referral for colonoscopy.

PTH-242 Symptom association in small bowel bacterial overgrowth and caecal mal-fermentation in a clinical population

<h3>Introduction</h3> Small bowel bacterial overgrowth (SIBO) is a condition defined as excessive bacterial load in the upper gut. SIBO can contribute to dyspeptic symptoms and altered bowel habit. The inappropriate fermentation of ingested nutrients in the upper gut produces gas (hydrogen and methane) and short chain fatty acids (SCFA’s), which can affect motility and sensation. Additionally colonic mal-fermentation is also thought to play a role in lower abdominal symptoms. This study attempted to assess symptom correlation to these disorders. <h3>Method</h3> Lactulose hydrogen-methane breath testing was used to detect SIBO. Peak hydrogen and methane production was retrospectively evaluated in 463 patients following ingestion of 25 ml (16.5 g) lactulose with water. Breath samples were taken every 15 min for up to two hours and symptoms of bloating (BL), abdominal pain (AP) and nausea (NA) were tracked throughout. Assuming normal oro-caecal time, a rise in breath hydrogen/methane &gt;10 ppm from baseline in the first 60 min of testing was defined positive for SIBO. A peak &gt;60ppm from baseline between 60–120 min was defined as excessive caecal fermentation. Patients with a history of bowel surgery or previous treatment for SIBO were excluded from the analysis. <h3>Results</h3> Data was available for 409/463 patients (162 Male, mean age 41, range 16–84). 288 (70.4%) had SIBO. At baseline, patients described symptoms of BL (323/409; 79.0%), AP (190/409; 46.5%), and NA (81/409; 19.8%). 228/323 (70.6%) with BL, 145/190 (76.3%) with AP and 66/81 (81.5%) with NA subsequently tested for SIBO. The prevalence of SIBO was similar in patients with diarrhoea (79/106; 74%) versus those with constipation (56/81; 69.1%; p &gt; 0.05). 66/409 individuals (16.1%) had baseline methane levels &gt;10 ppm. The likelihood of those with diarrhoea or constipation being methane producers was 8/106 (7.5%) and 25/81 (30.9%). 45/288 (15.6%) of individuals with SIBO were methane producers. Caecal mal-fermentation, in the presence of reproduced symptoms, was observed in 48.4% of individuals with a diagnosis of SIBO and 9% of individuals without a diagnosis of SIBO. <h3>Conclusion</h3> Although bloating was the most common symptom and nausea the least, nausea was more sensitive at indicating the presence of SIBO. Bowel habit did not appear to be useful at predicting SIBO. As expected, methane producers were more likely to have constipation with a significant percentage having concomitant SIBO. HMBT should be seen as a provocation test for patients with upper and lower bowel symptoms. <h3>Disclosure of interest</h3> None Declared.

The Performance of Asia-Pacific Colorectal Screenings Score in Predicting Advanced Colorectal Neoplasia in Vietnamese Patients With Lower Bowel Symptoms

The Asia-Pacific colorectal screening score (APCS) was recently developed to predict the risk of advanced colorectal neoplasia (ACN) in asymptomatic Asians. This study aims to: (1) define the prevalence of ACN; (2) evaluate the performance of APCS in predicting the risk of ACN in Vietnamese patients with lower bowel symptoms. Consecutive patients with lower bowel symptoms undergoing colonoscopy from January to May 2012 were prospectively enrolled in this cross-sectional study. APCS score for each patient was calculated by summing the points attributed by risk factors. Three tiers of risk were arbitrarily defined: 0–1 “average risk” (AR); 2–3 “moderate risk” (MR); 4–7 “high risk” (HR). The performance of APCS score in predicting risk of ACN was evaluated. Overall, 246 patients with excellent bowel preparation, and who had undergone complete colon examination were included (mean age, 47.8±14 years; male/female ratio, 1:1). Familial history of colorectal cancer was present in 5.3% (13/246) of subjects. The prevalence of ACN was 12.2% (30/246). Overall, 93 patients (37.8%) were in the AR tier, 104 (42.3%) in the MR tier and 49 (19.9%) in the HR tier. The prevalence of ACN in the AR, MR and HR groups was 3.2%, 14.4% and 23.5%, respectively. The prevalence of ACN in the MR and HR tiers was 5-fold (95% CI, 1.4–18.0) and 9.7-fold (95% CI, 2.6–36.5) that in the AR tier. The APCS score was useful in identifying patients with lower bowel symptoms at high risk of ACN in a cohort of Vietnamese population.

Development and validation of a clinical decision-making aid for screening bowel symptoms in community pharmacies

Bowel symptoms are common, and community pharmacies are an ideal setting for health advice about these symptoms. The aim of this study was to develop and validate a questionnaire for use with adults presenting to community pharmacies with lower bowel symptoms. The purpose of the questionnaire was to stratify people into those requiring medical follow-up for symptoms and those with self-limiting symptoms. A self-administered questionnaire, named the Jodi Lee test (JLT), was developed in three stages - review of the literature, questionnaire design and statistical validation - against a validated screening tool, the patient consultation questionnaire (PCQ), to assess the sensitivity and specificity of JLT. The questionnaire was developed to be simple, easy for all pharmacy staff to use and require no score calculation. Its application was designed to facilitate referral from pharmacy assistants to pharmacists and from pharmacists to medical practitioners. The questionnaire comprises eight questions. It has a Flesh-Kincaid reading score of 79.5. By considering different score thresholds on the PCQ, a receiver operator characteristic (ROC) curve was calculated to assess the effectiveness of the JLT. From a sample of 118 subjects, the area under the ROC curve was 0.94. At a threshold score of 30 on the PCQ, the sensitivity was 100%. The specificity was 65%. The JLT has high sensitivity for identifying patients with symptoms of serious bowel disease. It is also likely to identify patients who have symptoms of relatively benign disease who would benefit from medical advice.

Investigating the frail elderly patient with lower bowel symptoms: what do we do now and can we improve?

Aims: To assess the utility of flexible sigmoidoscopy (FS) and minimal preparation CT (MPCT) in investigating lower gastrointestinal (LGI) symptoms in elderly patients who are too frail to undergo colonoscopy or spiral CT.Methods: All FS examinations performed in patients aged over 70 between 1 January and 31 December 2008 were analysed. Predictors of usefulness were determined using multivariable analysis. In patients who also underwent MPCT, we analyzed the correlation between FS and MPCT.Results: 426 FS were performed. Bowel preparation was inadequate in 24% of procedures. Indications in which FS was useful were: radiological abnormality (odds ratio [OR] 9.32), history of polyps (OR 4.54) and rectal bleeding (OR 1.73). Indications for which FS was least useful were: change in bowel habit (OR 0.22), diarrhoea (OR 0.46) and constipation (OR 0.38).Conclusions: LGI investigation in frail elderly patients can be rationalised according to indication. Performing FS and MPCT together is not always necessary.

Lower bowel function in urinary incontinent women, urinary continent women and in controls

The anorectum and the lower urinary tract (LUT) are closely related. Clinically, it is important for caregivers to identify the presence of concomitant pathology as early in the diagnostic process as possible. This study evaluates lower bowel symptoms (LBS) in women with different types of urinary incontinence (UI), and compares the outcome with continent women and with a female control group. Female patients, consulting at the Functional Unit of our Urology Department, with or without UI, were included in the study (URO patients). A female control group was recruited at the Orthopedic and the General Internal Medicine Consultation and among co-workers from the hospital (CONTROL group). All were asked to complete a validated, self-administered questionnaire, which identified the possible presence of UI, allowed categorization by type of UI, and questioned LBS. URO patients had, regardless of presence and type of UI, more complaints of fecal incontinence (FI) and of constipation than the CONTROL group. Patients with Urge UI and Mixed UI had significantly more difficulty postponing defecation and significantly more FI than Stress UI (SUI) patients and than continent URO patients (27% vs. 8%). More SUI patients reported straining during defecation. Our data confirm that in patients with functional problems of the LUT, the prevalence of LBS is high. Bowel symptoms differ in different types of UI.

Do Pharmacists Know Which Patients with Bowel Symptoms Should Seek Further Medical Advice? A Survey of Pharmacists Practicing in Community Pharmacy in Western Australia

Pharmacists in Australia are routinely asked to advise people with lower bowel symptoms. Clinical, demographic, and working environment parameters may affect whether appropriate referral for advanced care is advised by pharmacists. To characterize how selected clinical, demographic, and working environment variables affect the likelihood of a pharmacist providing a referral for patients with lower bowel symptoms to consult a general practitioner, and to investigate factors associated with agreement with an expert panel and colorectal cancer guidelines. Self-administered questionnaires were distributed to a random sample of 300 pharmacists in Western Australia. Vignettes were constructed around 6 clinical variables and pharmacists were asked to describe a referral pathway. Logistic regression was used to identify factors associated with odds of referral and agreement with an expert panel. One hundred sixty-seven completed surveys were returned, giving a response rate of 56%. The odds of referral to a general practitioner were mostly associated with presenting symptoms, although lower odds of referral were observed with increasing volumes of weekly prescriptions. The odds of pharmacists agreeing with the expert panel for an urgent referral were 70% (95% CI 50 to 80) lower for weight loss as the presenting symptom compared to rectal bleeding. The expert panel considered weight loss or rectal bleeding of 4 weeks' duration as meriting an urgent referral, but 63% and 30% of pharmacists, respectively, disagreed. In contrast to cancer guidelines, over 60% of respondents did not consider persistent diarrhea in a 65-year-old patient as a likely symptom of significant bowel pathology. In general, pharmacists' patterns of referral were influenced by clinical symptoms and not by demographic or working environment variables. They over-referred patients with diarrhea but under-referred those with weight loss and rectal bleeding, according to the expert panel. This is a cause for concern because any unexplained rectal bleeding should be referred for further investigation.

Referring patients to specialists: a structured vignette survey of Australian and British GPs.

BackgroundIn Australia and in the United Kingdom (UK) access to specialists is sanctioned by General Practitioners (GPs). It is important to understand how practitioners determine which patients warrant referral.MethodsA self-administered structured vignette postal survey of General Practitioners in Western Australia and the United Kingdom. Sixty-four vignettes describing patients with colorectal symptoms were constructed encompassing six clinical details. Nine vignettes, chosen at random, were presented to each individual. Respondents were asked if they would refer the patient to a specialist and how urgently. Logistic regression and parametric tests were used to analyse the dataResultsWe received 260 completed questionnaires. 58% of 'cancer vignettes' were selected for 'urgent' referral. 1632/2367 or 69% of all vignettes were selected for referral. After adjusting for clustering the model suggests that 38.4% of the variability is explained by all the clinical variables as well as the age and experience of the respondents. 1012 or 42.8 % of vignettes were referred 'urgently'. After adjusting for clustering the data suggests that 31.3 % of the variability is explained by the model. The age of the respondents, the location of the practice and all the clinical variables were significant in the decision to refer urgently.ConclusionGPs' referral decisions for patients with lower bowel symptoms are similar in the two countries. We question the wisdom of streaming referrals from primary care without a strong evidence base and an effective intervention for implementing guidelines. We conclude that implementation must take into account the profile of patients but also the characteristics of GPs and referral policies.

Implementing referral guidelines: lessons from a negative outcome cluster randomised factorial trial in general practice.

BackgroundFew patients with lower bowel symptoms who consult their general practitioner need a specialist opinion. However data from referred patients suggest that those who are referred would benefit from detailed assessment before referral.MethodsA cluster randomised factorial trial. 44 general practices in North Trent, UK. Practices were offered either an electronic interactive referral pro forma, an educational outreach visit by a local colorectal surgeon, both or neither. The main outcome measure was the proportion of cases with severe diverticular disease, cancer or precancerous lesions and inflammatory bowel disease in those referred by each group. A secondary outcome was a referral letter quality score. Semi-structured interviews were conducted to identify key themes relating to the use of the softwareResultsFrom 150 invitations, 44 practices were recruited with a total list size of 265,707. There were 716 consecutive referrals recorded over a six-month period, for which a diagnosis was available for 514. In the combined software arms 14% (37/261) had significant pathology, compared with 19% (49/253) in the non-software arms, relative risk 0.73 (95% CI: 0.46 to 1.15). In the combined educational outreach arms 15% (38/258) had significant pathology compared with 19% (48/256) in the non-educational arms, relative risk 0.79 (95% CI: 0.50 to 1.24). Pro forma practices documented better assessment of patients at referral.ConclusionThere was a lack of evidence that either intervention increased the proportion of patients with organic pathology among those referred. The interactive software did improve the amount of information relayed in referral letters although we were unable to confirm if this made a significant difference to patients or their health care providers. The potential value of either intervention may have been diminished by their limited uptake within the context of a cluster randomised clinical trial. A number of lessons were learned in this trial of novel innovations.

The International Consultation on Incontinence Modular Questionnaire: www.iciq.net

In 1998 the first ICI was held in Monaco, sponsored by WHO and organized by the International Continence Society and International Consultation on Urological Diseases. The Scientific Committee recognized the need to develop a universally applicable questionnaire for wide application across international populations in clinical practice and research to assess urinary incontinence, facilitating the comparison of findings from different settings and studies, in a manner similar to the International Prostate Symptom Score. An Advisory Board was formed to steer the development of the ICIQ and a decision was made to extend the concept further, developing the ICIQ Modular Questionnaire. The first module developed was the ICIQ Short Form Questionnaire for urinary incontinence. ICIQ modules have been developed or adapted for urinary tract symptoms and they are being developed for vaginal and lower bowel symptoms. Additional sexual matters and quality of life modules will become available for each condition area. Modules to assess patient satisfaction are expected to be of particular use for assessing treatment effectiveness. The ICIQ Advisory Board recently proposed the development of the ICIQ website, which is anticipated to be crucial for informing potential users of the phase of development of all ICIQ modules. The ICIQ can offer a full range of urinary tract symptom questionnaires. The website will aim to attract collaborators committed to the concept of this internationally accepted modular questionnaire who are willing to help with its development.

Autonomic functioning during REM sleep differentiates IBS symptom subgroups.

The aim of this study was to investigate autonomic activity by means of heart rate variability analysis in a sample of irritable bowel syndrome (IBS) patients, allowing stratification into IBS symptom subgroups. Thirty-three female IBS patients (mean age 37 yr) and 21 healthy female controls (mean age 38 yr) participated. Patients were stratified into 16 subjects with only lower bowel symptoms (IBS only) and 17 subjects with both lower bowel and dyspeptic symptoms (IBS+D). The protocol included standard polysomnography to assess stages of sleep with concomitant electrocardiographic measurement of beat-to-beat intervals of the cardiac cycle. Fifteen-min segments were selected from presleep waking, stage 2 of non-rapid eye movement (REM), and REM sleep and analyzed by spectral analysis of heart rate variability to calculate the high-frequency band, a measure of vagal tone, and the low-frequency/high-frequency ratio, an indicator of sympathovagal balance. The high-frequency band power during REM sleep was significantly lower, indicating substantial vagal withdrawal in IBS-only patients compared with IBS+D patients and controls. The low-frequency/high-frequency band ratio was significantly higher during REM sleep for IBS-only patients. IBS-only patients had greater sympathetic dominance, indicated by elevated low-frequency/high-frequency band ratio, during REM sleep because of vagal withdrawal. Autonomic functioning, unique to REM sleep, differentiates IBS symptom subgroups, suggesting that autonomic functioning during REM sleep may be a useful biological marker to identify IBS patient subgroups.

Autonomic functioning during REM sleep differentiates IBS symptom subgroups

OBJECTIVE: The aim of this study was to investigate autonomic activity by means of heart rate variability analysis in a sample of irritable bowel syndrome (IBS) patients, allowing stratification into IBS symptom subgroups. METHODS: Thirty-three female IBS patients (mean age 37 yr) and 21 healthy female controls (mean age 38 yr) participated. Patients were stratified into 16 subjects with only lower bowel symptoms (IBS only) and 17 subjects with both lower bowel and dyspeptic symptoms (IBS+D). The protocol included standard polysomnography to assess stages of sleep with concomitant electrocardiographic measurement of beat-to-beat intervals of the cardiac cycle. Fifteen-min segments were selected from presleep waking, stage 2 of non-rapid eye movement (REM), and REM sleep and analyzed by spectral analysis of heart rate variability to calculate the high-frequency band, a measure of vagal tone, and the low-frequency/high-frequency ratio, an indicator of sympathovagal balance. RESULTS: The high-frequency band power during REM sleep was significantly lower, indicating substantial vagal withdrawal in IBS-only patients compared with IBS+D patients and controls. The low-frequency/high-frequency band ratio was significantly higher during REM sleep for IBS-only patients. CONCLUSIONS: IBS-only patients had greater sympathetic dominance, indicated by elevated low-frequency/high-frequency band ratio, during REM sleep because of vagal withdrawal. Autonomic functioning, unique to REM sleep, differentiates IBS symptom subgroups, suggesting that autonomic functioning during REM sleep may be a useful biological marker to identify IBS patient subgroups.

Autonomic functioning during REM sleep differentiates IBS symptom subgroups

Abstract OBJECTIVE: The aim of this study was to investigate autonomic activity by means of heart rate variability analysis in a sample of irritable bowel syndrome (IBS) patients, allowing stratification into IBS symptom subgroups. METHODS: Thirty-three female IBS patients (mean age 37 yr) and 21 healthy female controls (mean age 38 yr) participated. Patients were stratified into 16 subjects with only lower bowel symptoms (IBS only) and 17 subjects with both lower bowel and dyspeptic symptoms (IBS+D). The protocol included standard polysomnography to assess stages of sleep with concomitant electrocardiographic measurement of beat-to-beat intervals of the cardiac cycle. Fifteen-min segments were selected from presleep waking, stage 2 of non-rapid eye movement (REM), and REM sleep and analyzed by spectral analysis of heart rate variability to calculate the high-frequency band, a measure of vagal tone, and the low-frequency/high-frequency ratio, an indicator of sympathovagal balance. RESULTS: The high-frequency band power during REM sleep was significantly lower, indicating substantial vagal withdrawal in IBS-only patients compared with IBS+D patients and controls. The low-frequency/high-frequency band ratio was significantly higher during REM sleep for IBS-only patients. CONCLUSIONS: IBS-only patients had greater sympathetic dominance, indicated by elevated low-frequency/high-frequency band ratio, during REM sleep because of vagal withdrawal. Autonomic functioning, unique to REM sleep, differentiates IBS symptom subgroups, suggesting that autonomic functioning during REM sleep may be a useful biological marker to identify IBS patient subgroups.

6980 Absence of diverticular disease in a group of patients with colorectal carcinoma.

Introduction - A diet high in fat and low in fibre is thought to be of importance in the etiology of both colorectal carcinoma and diverticular disease. The incidence of diverticular disease has been shown to be lower in developing than in developed countries, but the co-existence of diverticular disease in patients with histologically proven colorectal carcinoma has not previously been studied in developing countries. Patients and methods - A retrospective review was carried out of consecutive patients who underwent lower endoscopy to the caecum at a tertiary referral cancer centre between May 1995 and September 1999 to ascertain the frequency of both diverticular disease and colorectal carcinoma in this group. 335 complete studies were performed in 311 patients (60% males, n=186; mean age 45.3y, range 5-91y), to investigate lower bowel symptoms or to confirm a diagnosis of colorectal carcinoma made at another institution. Results - Tumours were found in 45 patients, 36 of whom (64% males, n=23; mean age 46.8y, range 18-70y), had adenocarcinoma on histology. The incidence of adenocarcinoma in our group was 11.6% (36/311). None of these 36 patients had diverticular disease. Diverticular disease was seen in only 2/311 patients (0.64%), neither of whom had a tumour of the colon. Diverticulae were present in the sigmoid colon in one and in the descending colon in the other patient. No patient had right-sided diverticular disease. Conclusion - There was a very low incidence (0.64%) of diverticular disease in this group of 311 patients who underwent lower endoscopy to the caecum. The low incidence of diverticular disease in this patient group, 11.6% of whom had confirmed colorectal carcinoma, suggests that other environmental or genetic factors may be more important in the etiology of colorectal carcinoma in these patients than diet. This factor needs to be borne in mind by those investigating the etiology of colorectal carcinoma in these patients.