A176 ASSOCIATIONS OF ANTIBIOTICS, HORMONAL THERAPIES, ORAL CONTRACEPTIVES, AND LONG-TERM NSAIDS WITH INFLAMMATORY BOWEL DISEASE: RESULTS FROM THE PROSPECTIVE URBAN RURAL EPIDEMIOLOGY (PURE) STUDY

Background

The pathogenesis of inflammatory bowel disease (IBD) which includes Crohn’s disease (CD) and ulcerative colitis (UC), is believed to involve activation of the intestinal immune system in response to the gut microbiome among genetically susceptible hosts. IBD has been historically regarded as a disease of developed nations, though in the past two decades there has been a reported shift in the epidemiological pattern of disease. High-income nations with known high prevalence of disease are seeing a stabilization of incident cases, while a rapid rise of incident IBD is being observed in developing nations. This suggests that environmental exposures may play a role in mediating the risk of developing IBD. The potential environmental determinants of IBD across various regions is vast, though medications have been increasingly recognized as one broad category of risk factors.

Purpose

Several medications have been considered to contribute to the etiology of IBD. This study assessed the association between medication use and risk of developing IBD using the Prospective Urban Rural Epidemiology (PURE) cohort.

Method

This was a prospective cohort study of 133,137 individuals between the ages of 20-80 from 24 countries. Country-specific validated questionnaires documented baseline and follow-up medication use. Participants were followed prospectively at least every 3 years. The main outcome was development of IBD, including CD and UC. Short-term (baseline but not follow-up use) and long-term use (baseline and subsequent follow-up use) was evaluated. Results are presented as adjusted odds ratios (aOR) with 95% confidence intervals (CI).

Result(s)

During the median follow-up of 11.0 years [interquartile range (IQR) 9.2-12.2], we recorded 571 incident cases of IBD (143 CD and 428 UC). Higher risk of incident IBD was associated with baseline antibiotic use [aOR: 2.81 (95% CI: 1.67-4.73), p=0.0001] and hormonal medication use [aOR: 4.43 (95% CI: 1.78-11.01), p=0.001]. Among females, previous or current oral contraceptive use was also associated with IBD development [aOR: 2.17 (95% CI: 1.70-2.77), p=5.02E-10]. NSAID users were also observed to have increased risk of IBD [aOR: 1.80 (95% CI: 1.23-2.64), p=0.002], which was driven by long-term users [aOR: 5.58 (95% CI: 2.26-13.80), p<0.001]. All significant results were consistent in direction for CD and UC with low heterogeneity.

Conclusion(s)

Antibiotics, hormonal medications, oral contraceptives, and long-term NSAID use were associated with increased odds of incident IBD after adjustment for covariates.

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Salim Yusuf is supported by the Heart & Stroke Foundation/Marion W. Burke Chair in Cardiovascular Disease. The PURE Study is an investigator-initiated study funded by the Population Health Research Institute, the Canadian Institutes of Health Research (CIHR), Heart and Stroke Foundation of Ontario, support from CIHR’s Strategy for Patient Oriented Research (SPOR) through the Ontario SPOR Support Unit, as well as the Ontario Ministry of Health and Long-Term Care and through unrestricted grants from several pharmaceutical companies, with major contributions from AstraZeneca (Canada), Sanofi-Aventis (France and Canada), Boehringer Ingelheim (Germany and Canada), Servier, and GlaxoSmithkline, and additional contributions from Novartis and King Pharma and from various national or local organisations in participating countries; these include: Argentina: Fundacion ECLA; Bangladesh: Independent University, Bangladesh and Mitra and Associates; Brazil: Unilever Health Institute, Brazil; Canada: Public Health Agency of Canada and Champlain Cardiovascular Disease Prevention Network; Chile: Universidad de la Frontera; China: National Center for Cardiovascular Diseases; Colombia: Colciencias, grant number 6566-04-18062; India: Indian Council of Medical Research; Malaysia: Ministry of Science, Technology and Innovation of Malaysia, grant numbers 100 -IRDC/BIOTEK 16/6/21 (13/2007) and 07-05-IFN-BPH 010, Ministry of Higher Education of Malaysia grant number 600 -RMI/LRGS/5/3 (2/2011), Universiti Teknologi MARA, Universiti Kebangsaan Malaysia (UKM-Hejim-Komuniti-15-2010); occupied Palestinian territory: the UN Relief and Works Agency for Palestine Refugees in the Near East, occupied Palestinian territory; International Development Research Centre, Canada; Philippines: Philippine Council for Health Research & Development; Poland: Polish Ministry of Science and Higher Education grant number 290/W-PURE/2008/0, Wroclaw Medical University; Saudi Arabia: the Deanship of Scientific Research at King Saud University, Riyadh, Saudi Arabia (research group number RG -1436-013); South Africa: the North-West University, SANPAD (SA and Netherlands Programme for Alternative Development), National Research Foundation, Medical Research Council of SA, The SA Sugar Association (SASA), Faculty of Community and Health Sciences (UWC); Sweden: grants from the Swedish state under the Agreement concerning research and education of doctors; the Swedish Heart and Lung Foundation; the Swedish Research Council; the Swedish Council for Health, Working Life and Welfare, King Gustaf V’s and Queen Victoria Freemasons Foundation, AFA Insurance, Swedish Council for Working Life and Social Research, Swedish Research Council for Environment, Agricultural Sciences and Spatial Planning, grant from the Swedish State under the Läkar Utbildnings Avtalet agreement, and grant from the Västra Götaland Region; Turkey: Metabolic Syndrome Society, AstraZeneca, Turkey, Sanofi Aventis, Turkey; United Arab Emirates (UAE): Sheikh Hamdan Bin Rashid Al Maktoum Award For Medical Sciences and Dubai Health Authority, Dubai UAE.

Disclosure of Interest

C. Pray: None Declared, N. Narula Grant / Research support from: Neeraj Narula holds a McMaster University Department of Medicine Internal Career Award. Neeraj Narula has received honoraria from Janssen, Abbvie, Takeda, Pfizer, Merck, and Ferring, E. C. Wong: None Declared, J. K. Marshall Grant / Research support from: John K. Marshall has received honoraria from Janssen, AbbVie, Allergan, Bristol-Meyer-Squibb, Ferring, Janssen, Lilly, Lupin, Merck, Pfizer, Pharmascience, Roche, Shire, Takeda and Teva., S. Rangarajan: None Declared, S. Islam: None Declared, A. Bahonar: None Declared, K. F. Alhabib: None Declared, A. Kontsevaya: None Declared, F. Ariffin: None Declared, H. U. Co: None Declared, W. Al Sharief: None Declared, A. Szuba: None Declared, A. Wielgosz: None Declared, M. L. Diaz: None Declared, R. Yusuf: None Declared, L. Kruger: None Declared, B. Soman: None Declared, Y. Li: None Declared, C. Wang: None Declared, L. Yin: None Declared, M. Erkin: None Declared, F. Lanas: None Declared, K. Davletov: None Declared, A. Rosengren: None Declared, P. Lopez-Jaramillo: None Declared, R. Khatib: None Declared, A. Oguz: None Declared, R. Iqbal: None Declared, K. Yeates: None Declared, Á. Avezum: None Declared, W. Reinisch Consultant of: Speaker for Abbott Laboratories, Abbvie, Aesca, Aptalis, Astellas, Centocor, Celltrion, Danone Austria, Elan, Falk Pharma GmbH, Ferring, Immundiagnostik, Mitsubishi Tanabe Pharma Corporation, MSD, Otsuka, PDL, Pharmacosmos, PLS Education, Schering-Plough, Shire, Takeda, Therakos, Vifor, Yakult, Consultant for Abbott Laboratories, Abbvie, Aesca, Algernon, Amgen, AM Pharma, AMT, AOP Orphan, Arena Pharmaceuticals, Astellas, Astra Zeneca, Avaxia, Roland Berger GmBH, Bioclinica, Biogen IDEC, Boehringer-Ingelheim, Bristol-Myers Squibb, Cellerix, Chemocentryx, Celgene, Centocor, Celltrion, Covance, Danone Austria, DSM, Elan, Eli Lilly, Ernest & Young, Falk Pharma GmbH, Ferring, Galapagos, Genentech, Gilead, Grünenthal, ICON, Index Pharma, Inova, Janssen, Johnson & Johnson, Kyowa Hakko Kirin Pharma, Lipid Therapeutics, LivaNova, Mallinckrodt, Medahead, MedImmune, Millenium, Mitsubishi Tanabe Pharma Corporation, MSD, Nash Pharmaceuticals, Nestle, Nippon Kayaku, Novartis, Ocera, Omass, Otsuka, Parexel, PDL, Periconsulting, Pharmacosmos, Philip Morris Institute, Pfizer, Procter & Gamble, Prometheus, Protagonist, Provention, Robarts Clinical Trial, Sandoz, Schering-Plough, Second Genome, Seres Therapeutics, Setpointmedical, Sigmoid, Sublimity, Takeda, Therakos, Theravance, Tigenix, UCB, Vifor, Zealand, Zyngenia, and 4SC, Advisory board member for Abbott Laboratories, Abbvie, Aesca, Amgen, AM Pharma, Astellas, Astra Zeneca, Avaxia, Biogen IDEC, Boehringer-Ingelheim, Bristol-Myers Squibb, Cellerix, Chemocentryx, Celgene, Centocor, Celltrion, Danone Austria, DSM, Elan, Ferring, Galapagos, Genentech, Grünenthal, Inova, Janssen, Johnson & Johnson, Kyowa Hakko Kirin Pharma, Lipid Therapeutics, MedImmune, Millenium, Mitsubishi Tanabe Pharma Corporation, MSD, Nestle, Novartis, Ocera, Otsuka, PDL, Pharmacosmos, Pfizer, Procter & Gamble, Prometheus, Sandoz, Schering-Plough, Second Genome, Setpointmedical, Takeda, Therakos, Tigenix, UCB, Zealand, Zyngenia, and 4SC, P. Moayyedi: None Declared, S. Yusuf: None Declared

A218 ASSOCIATIONS BETWEEN ADHERENCE TO LITERATURE-DERIVED DIETARY INDICES AND PRE-DISEASE BIOMARKERS: IMPLICATIONS FOR CROHN’S DISEASE PREVENTION

Background

The incidence of Crohn’s disease (CD) is increasing globally, indicating a significant environmental influence such as diet. A plethora of dietary adherence (DA) patterns exist in the literature: the Mediterranean Diet (MD), Empirical Dietary Inflammatory Pattern (EDIP), Specific Carbohydrate Diet (SCD), and low Fermentable Oligosaccharide, Disaccharide, Monosaccharide, or Polyol diet (FODMAP) are all potential candidates to maintain a reduced level of inflammation, improving gastrointestinal function. Contrary, the Westernized diet (WD) is generally reported as a diet promoting inflammation in humans.

Purpose

To determine if DA to literature-derived dietary indices in a cohort of first-degree relatives (FDRs) of CD patients can modulate pre-disease biomarkers.

Method

We used food frequency questionnaire (FFQ) data from 2,696 healthy FDR subjects of the Crohn’s Colitis Canada- Genes, Environment, Microbial (CCC-GEM) project. We rederived each of the following scores using our FFQ data, utilizing originally described methods for the MD, EDIP, SCD, low FODMAP, and WD to obtain DA. Each diet was correlated pairwise via Kendall’s Tau.

We fit multivariable regression models to identify the association of DA (top quintile vs remaining) and: i) intestinal permeability using urinary fractional excretion of lactulose to mannitol ratio (LMR), LMR≥0.03 defined abnormal; ii) subclinical inflammation using fecal calprotectin (FCP) measured with BÜHLMANN fCAL® ELISA, FCP≥250µg/g defined inflammation; and iii) fecal microbiome richness and composition using 16S rRNA sequencing. Two-sided p<0.05 for primary and q<0.05 for secondary analysis defined significance.

Result(s)

There were positive correlations between the MD, SCD, and low FODMAP, these diets negatively correlated with the WD. The EDIP negatively correlated with the SCD and low FODMAP, did not correlate with the MD, and positively correlated with the WD. No diet was associated with abnormal LMR or FCP. Only the SCD was associated with increased microbial richness (q=0.03). All diets were associated with microbial genera: the MD (n=18 taxa, (2.0^-7<q-values< 0.04), EDIP (n=9, [2.8^-4-0.05]), SCD (n=13, [3.7^-11-0.05]), low FODMAP (n=14, [1.3^-7-0.05]), and WD (n=1, [0.03]).

Conclusion(s)

This study shows that literature-derived dietary indices correlate generally with each other, yet none were not associated with abnormal LMR or FCP. However, we found that diet can impact microbiome richness and composition. Thus, it is tempting to speculate that diet is a possible intervention capable of maintain microbiome homeostasis to reduce future risk of CD.

Submitted on behalf of the CCC-GEM consortium.

Funding

Crohn’s and Colitis Canada Genetics Environment Microbial (CCC-GEM) III

The Leona M. and Harry B. Helmsley Charitable Trust

Kenneth Croitoru is the recipient of the Canada Research Chair in Inflammatory Bowel Disease

Disclosure of Interest

None Declared

A238 BILE ACID COMPOSITION AND DIETARY FAT: IMPLICATIONS FOR CROHN’S DISEASE IN A COHORT OF HEALTHY FIRST-DEGREE RELATIVES

Background

Crohn’s disease (CD) is a chronic relapsing inflammatory disease of the gastrointestinal tract. The etiology of CD may arise from complex interactions including host genetics, diet, and the intestinal microbiome. Increased consumption of saturated fats, characteristic of the Western diet, is a known risk factor for CD. Dietary fat (DF) is absorbed by the host through the release of primary bile acids (PBAs) and bio-transformed by the microbiome into secondary bile acids (SBAs). Altogether, bile acids (BAs) can act as signaling molecules involved in host immune regulation and potentially in CD onset.

Purpose

To investigate the relationship between CD risk, BAs, and DF, and evaluate the predictive performance of CD onset of these factors by developing machine learning models.

Method

We used samples healthy first-degree relatives (FDRs) recruited as part of the Crohn’s Colitis Canada- Genes, Environment, Microbial (GEM) project. Those who developed CD (n=87) were matched 1:4 by age, sex, follow-up time, and geographic location with control FDRs remaining healthy (n=347).

Serum, urine, and stool BA were measured using ultrahigh Performance Liquid Chromatography-Tandem Mass Spectroscopy. DF types were derived from food frequency questionnaire data. We used conditional logistic regressions to identify associations between CD onset, BAs (n=93), and DFs (n=9). We further explored the relationships of significant CD-related BAs and DF via Generalized Estimation Equations. Finally, we used a tree-based machine-learning algorithm (XGBoost) with 5-fold cross-validation to assess the prediction performance of CD onset using BA from all sources as well as DF. Two-sided p<0.05 was considered significant.

Result(s)

In total, 10 of 93 BAs, and two of nine DFs were significantly associated with increased odds of CD onset (p<0.05). Additionally, five BAs were significantly associated with DF (p<0.05). Serum-derived BAs had the best predictive performance for CD, with a mean AUC of 0.70 [95% CI: 0.63;0.76], followed by stool derived BAs with a mean AUC= 0.65 [0.55;0.75], and followed by urine derived Bas with a mean AUC= 0.57 [0.48;0.66]. Lastly DF was not a predictive marker of CD onset with a mean AUC= 0.50 [0.41;0.60].

Conclusion(s)

This study suggests that BAs are associated with the pathogenesis of CD and the effects may be influenced by DF. Serum-derived BAs may be able to better predict the risk of CD than other stool or urine derived BA, while DF is not directly implicated in CD risk.

Submitted on behalf of the CCC-GEM consortium.

Funding

Crohn’s and Colitis Canada Genetics Environment Microbial (CCC-GEM) III

The Leona M. and Harry B. Helmsley Charitable Trust

Kenneth Croitoru is the recipient of the Canada Research Chair in Inflammatory Bowel Diseases

The International Organization for the Study of Inflammatory Bowel Diseases (IOIBD)

Jingcheng Shao is the recipient of a Data Science Institute Summer Undergraduate Data Science award

Disclosure of Interest

None Declared

Declining Use of Corticosteroids for Crohn's Disease Has Implications for Study Recruitment: Results of a Pilot Randomized Controlled Trial

Background

Corticosteroids (CS) have been used extensively to induce remission in Crohn’s disease (CD); however, they are associated with severe side effects. We hypothesized that the administration of an exclusive enteral nutrition (EEN) formula to CS would lead to increased CD remission rates and to decreased CS-related adverse events. We proposed to undertake a pilot study comparing EEN and CS therapy to CS alone to assess decrease symptoms and inflammatory markers over 6 weeks.

Aim

The overall aim was to assess study feasibility based on recruitment rates and acceptability of treatment in arms involving EEN

Methods

The pilot study intended to recruit 100 adult patients with active CD who had been prescribed CS to induce remission as part of their care. The patients were randomized to one of three arms: (i) standard-dose CS; (ii) standard-dose CS plus EEN (Modulen 1.5 kcal); or (iii) short-course CS plus EEN.

Results

A total of 2009 CD patients attending gastroenterology clinics were screened from October 2018 to November 2019. Prednisone was prescribed to only 6.8% (27/399) of patients with active CD attending outpatient clinics. Of the remaining 372 patients with active CD, 34.8% (139/399) started or escalated immunosuppressant or biologics, 49.6% (198/399) underwent further investigation and 8.8% (35/399) were offered an alternative treatment (e.g., antibiotics, surgery or investigational agents in clinical trials). Only three patients were enrolled in the study (recruitment rate 11%; 3/27), and the study was terminated for poor recruitment.

Conclusion

The apparent decline in use of CS for treatment of CD has implications for CS use as an entry criterion for clinical trials.

Review article: a clinician's guide for therapeutic drug monitoring of infliximab in inflammatory bowel disease

BACKGROUND

Tumour necrosis factor (TNF)-antagonists have an established role in the treatment of inflammatory bowel diseases (IBDs), however, subtherapeutic drug levels and the formation of anti-drug antibodies (ADAs) may decrease their efficacy.

AIM

The evidence supporting the use of therapeutic drug monitoring (TDM) based clinical algorithms for infliximab (IFX) and their role in clinical practice will be discussed.

METHODS

The literature was reviewed to identify relevant articles on the measurement of IFX levels and antibodies-to-infliximab.

RESULTS

Treatment algorithms for IBD have evolved from episodic monotherapy used in patients refractory to all other treatments, to long-term combination therapy initiated early in the disease course. Improved remission rates have been observed with this paradigm shift, nevertheless many patients ultimately lose response to therapy. Although empiric dose optimization or switching agents constitute the current standard of care for secondary failure, these interventions have not been applied in an evidence-based manner and are probably not cost-effective. Multiple TDM-based algorithms have been developed to identify patients that may benefit from measurement of IFX and ADA levels to guide adjustments to therapy.

CONCLUSIONS

Therapeutic drug monitoring offers a rational approach to the management of secondary failure to IFX. This concept has gained momentum based on evidence from case series, cohort studies and post-hoc analyses of randomised controlled trials.

Meta-analysis: peri-operative anti-TNFα treatment and post-operative complications in patients with inflammatory bowel disease

BACKGROUND

The impact of peri-operative use of TNFα antagonists on post-operative complications such as infection and wound healing is controversial.

AIM

To conduct a systematic review and meta-analysis to assess the impact of peri-operative use of TNFα antagonists on post-operative complications such as infection and wound healing in patients with inflammatory bowel disease (IBD).

METHODS

A literature search identified studies that investigated post-operative outcomes in patients with IBD using TNFα antagonists. The primary outcome was the rate of post-operative infectious complications. Secondary outcomes included the rates of non-infectious complications and total complications. Odds ratios (OR) with 95% confidence intervals (CI) are reported.

RESULTS

Overall, 18 studies with 4659 participants were eligible for inclusion. Patients with IBD using preoperative anti-TNFα therapies had significant increases in post-operative infectious [OR 1.56 (95% CI, 1.09-2.24)], non-infectious [OR 1.57 (95% CI, 1.14-2.17)] and total complications [OR 1.73 (95% CI, 1.23-2.43)]. Studies limited to patients with Crohn's disease demonstrated a statistically significant increase in infectious (OR 1.93, 95% CI 1.28-2.89) and total (OR 2.19, 95% CI 1.69-2.84) complications, and a trend towards increase in non-infectious complications (OR 1.73, 95% CI 0.94-3.17). Studies of patients with ulcerative colitis did not demonstrate significant increases in infectious (OR 1.39, 95% CI 0.56-3.45), non-infectious (OR 1.40, 95% CI 0.68-2.85), or total complications (OR 1.10, 95% CI 0.81-1.47).

CONCLUSION

Anti-TNFα therapies appear to increase the risk of post-operative complications. The increase in risk is small, and may well reflect residual confounding rather than a true biological effect. Nevertheless, physicians should exercise caution when continuing biological therapies during the peri-operative period.

Meta-analysis: colonoscopic post-polypectomy bleeding in patients on continued clopidogrel therapy

BACKGROUND

Current guidelines recommend the cessation of clopidogrel therapy 5 days and 7-10 days prior to colonoscopic polypectomy. Recent studies have advocated for continued clopidogrel as post-polypectomy bleeding (PPB) rates have been similar to those in the general population not on antithrombotic therapy.

AIM

To assess colonoscopic post-polypectomy bleeding in patients on continued clopidogrel therapy.

METHODS

A literature search was conducted for studies that investigated PPB in patients on continued clopidogrel therapy. The primary outcome of interest was the pooled relative risk ratio (RR) of colonoscopic PPB in patients on continued clopidogrel therapy vs. controls. Secondary outcomes were a comparison of immediate and delayed colonoscopy PPB in patients on continued clopidogrel therapy vs. controls.

RESULTS

Five observational studies included 574 subjects on continued clopidogrel therapy and 6169 control subjects. The pooled RR for PPB on continued clopidogrel therapy was 2.54 (95% CI 1.68-3.84, P < 0.00001). For immediate PPB there was a nonsignificant pooled RR of 1.76 (95% CI 0.90-3.46, P = 0.10), and delayed PPB there was a significant pooled RR of 4.66 (95% CI 2.37-9.17, P < 0.00001).

CONCLUSIONS

The results of this meta-analysis suggest that continued clopidogrel increases the risk of delayed but not immediate post-polypectomy bleeding. Clopidogrel interruption in individuals with coronary artery disease predisposes to serious acute ischaemic events. In high-risk patients, endoscopists should be cognisant of these risks and consider deferring elective colonoscopy and polypectomy until it is considered safe to interrupt clopidogrel therapy.

Dietary cholesterol increases paraoxonase 1 enzyme activity

HDL-associated paraoxonase 1 (PON1) activity has been consistently associated with cardiovascular and other diseases. Vitamins C and E intake have previously been positively associated with PON1 in a subset of the Carotid Lesion Epidemiology and Risk (CLEAR) cohort. The goal of this study was to replicate these findings and determine whether other nutrient intake affected PON1 activity. To predict nutrient and mineral intake values, 1,402 subjects completed a standardized food frequency survey of their dietary habits over the past year. Stepwise regression was used to evaluate dietary and covariate effects on PON1 arylesterase activity. Five dietary components, cholesterol (P < 2.0 × 10(-16)), alcohol (P = 8.51 × 10(-8)), vitamin C (P = 7.97 × 10(-5)), iron (P = 0.0026), and folic acid (0.037) were independently predictive of PON1 activity. Dietary cholesterol was positively associated and predicted 5.5% of PON1 activity, second in variance explained. This study presents a novel finding of dietary cholesterol, iron, and folic acid predicting PON1 activity in humans and confirms prior reported associations, including that with vitamin C. Identifying and understanding environmental factors that affect PON1 activity is necessary to understand its role and that of HDL in human disease.

Clustering and stability of functional lower gastrointestinal symptom after enteric infection

BACKGROUND

Current diagnostic criteria for functional gut disorder are based on symptom clusters observed after sporadic onset. It remains unclear whether symptoms group similarly in functional disorders of postinfectious etiology. We utilized observational data from the Walkerton Health Study (WHS) to: (i) determine groupings of functional gastrointestinal symptoms among patients exposed to acute gastroenteritis (GE), and (ii) assess the stability of these symptoms grouping over time.

METHODS

WHS participants 16 years of age and older at the time of the outbreak were included, if they had completed a modified Talley's Bowel Disease Questionnaire (BDQ) and responded 'yes' to a screening question as to whether they had experienced abdominal pain in the last 2 weeks. Exploratory factor analysis (EFA) using tetrachoric correlations was undertaken to identify symptom constructs. Hierarchical cluster analysis using the k-means method was used to create cluster groupings of patients based on these factors. Confirmatory factors analysis using responses to BDQ questionnaire administered at 4, 6, and 8 years after the outbreak was performed to assess stability of symptom domains over time.

KEY RESULTS

A total of 773 participants were eligible for inclusion [62.2% female, mean age 43.1 years (SD = 16.9)]. Eighty-four percent were exposed to acute GE during the outbreak. Two symptom groupings of abdominal pain with either diarrhea or constipation together explained 85.7% of the total variance. Cluster analysis identified four patients groupings based on these factors. These clusters could be qualitatively described as diarrhea- and constipation-predominant, mixed bowel pattern, and no predominance of bowel movements abnormalities. Results of the confirmatory factor analysis validating symptom domains identified in Year 1 showed that the baseline model was acceptable at 4 and 6 years after the outbreak and approached acceptability at 8 years. Values of root mean square error of approximation were 0.071 (90% CI: 0.053, 0.089) at 4 and 0.071 (90% CI: 0.049, 0.092) at 6 years and 0.089 (90% CI: 0.065, 0.114) at 8 years.

CONCLUSIONS & INFERENCES

The majority of subjects with postinfectious functional bowel disorders belong to groups with symptoms of abdominal pain and either diarrhea or constipation. These symptom groupings were stable across time.

Analysis of recently identified dyslipidemia alleles reveals two loci that contribute to risk for carotid artery disease

Background

Genome-wide association studies have identified numerous single nucleotide polymorphisms (SNPs) affecting high density lipoprotein (HDL) or low density lipoprotein (LDL) cholesterol levels; these SNPs may contribute to the genetic basis of vascular diseases.

Results

We assessed the impact of 34 SNPs at 23 loci on dyslipidemia, key lipid sub-phenotypes, and severe carotid artery disease (CAAD) in a case-control cohort. The effects of these SNPs on HDL and LDL were consistent with those previously reported, and we provide unbiased estimates of the percent variance in HDL (3.9%) and LDL (3.3%) explained by genetic risk scores. We assessed the effects of these SNPs on HDL subfractions, apolipoprotein A-1, LDL buoyancy, apolipoprotein B, and lipoprotein (a) and found that rs646776 predicts apolipoprotein B level while rs2075650 predicts LDL buoyancy. Finally, we tested the role of these SNPs in conferring risk for ultrasonographically documented CAAD stenosis status. We found that two loci, chromosome 1p13.3 near CELSR2 and PSRC1 which contains rs646776, and 19q13.2 near TOMM40 and APOE which contains rs2075650, harbor risk alleles for CAAD.

Conclusion

Our analysis of 34 SNPs contributing to dyslipidemia at 23 loci suggests that genetic variation in the 1p13.3 region may increase risk of CAAD by increasing LDL particle number, whereas variation in the 19q13.2 region may increase CAAD risk by promoting formation of smaller, denser LDL particles.

Systematic review and meta-analysis: The incidence and prognosis of post-infectious irritable bowel syndrome

BACKGROUND

Individual studies suggest that post-infectious irritable bowel syndrome is common, but symptoms gradually improve.

AIM

To review evidence for an association between intestinal infection and development of irritable bowel syndrome, assess the prognosis of post-infectious irritable bowel syndrome and explore factors that increase the risk.

METHODS

MEDLINE (1966-2007) and EMBASE (1980-2007) databases were searched to identify the studies of post-infectious irritable bowel syndrome epidemiology. Data were extracted by two independent reviewers. Pooled odds ratios (POR) and corresponding 95% CI for incidence of irritable bowel syndrome were estimated among the exposed and unexposed groups.

RESULTS

Eighteen of 26 studies identified were eligible for inclusion. Intestinal infection was associated with increased odds of developing irritable bowel syndrome at study end (POR = 5.86; 95% CI: 3.60-9.54). In subgroup analysis, the odds of developing irritable bowel syndrome was increased at 3 months (POR = 7.58; 95% CI: 4.27-13.45), 6 months (POR = 5.18; 95% CI: 3.24-8.26), 12 months (POR = 6.37; 95% CI: 2.63-15.40) and 24-36 months (POR = 3.85; 95% CI: 2.95-5.02). Among all studies (controlled and uncontrolled), the pooled incidence of irritable bowel syndrome at study conclusion was 10% (95% CI: 9.4-85.6). Subjects with post-infectious irritable bowel syndrome were younger and more anxious and depressed than those without post-infectious irritable bowel syndrome.

CONCLUSION

The odds of developing irritable bowel syndrome are increased sixfold after acute gastrointestinal infection. Young age, prolonged fever, anxiety and depression are risk factors for post-infectious irritable bowel syndrome.

Effects of commensal bacteria on intestinal morphology and expression of proinflammatory cytokines in the gnotobiotic pig

A germ-free neonatal pig model was established to determine the effects of bacterial colonization by different species on small intestinal morphology and proinflammatory cytokine gene expression. Two experimental groups of 16 pigs were aseptically delivered by cesarian section and allocated into 4 gnotobiotic isolators. Pigs were either maintained germ-free (GF), or were orally inoculated with either a single strain of nonpathogenic Escherichia coli (EC) or Lactobacillus fermentum (LF) or conventionalized with adult porcine feces (CV). After 13 days tissue samples were collected at 5 regions corresponding to 5%, 25%, 50%, 75%, and 95% of the small intestine (SI) length. In Experiment 2, the GF isolator became contaminated with Staphylococcus epidermidis (SE). In general, intestinal responses to bacterial colonization were similar among GF, LF, and SE pigs, and intestinal responses in EC pigs were more similar to CV pigs. Responses to bacterial colonization were most pronounced in the distal SI regions (50%-95%), suggesting that nonmicrobial factors may be more important in the proximal SI. Relative to CV pigs, the distal intestines of GF, LF, and SE pigs were characterized by long villi, shallow crypts, increased relative intestinal mass, and decreased lamina propria cellularity, whereas SI morphology was intermediate in EC pigs. Relative expression of proinflammatory cytokines interleukin-1beta (IL-1beta ) and IL-6 generally increased distally in the SI and was highest in EC and CV pigs. We observed regional variation in SI morphology and proinflammatory cytokine expression, which differed with bacterial species. This study demonstrates that bacterial species differentially affect intestinal morphology and expression of proinflammatory cytokines and suggests that neonatal bacterial colonization patterns may have long-term effects on intestinal health and development.

Intestinal permeability in patients with irritable bowel syndrome after a waterborne outbreak of acute gastroenteritis in Walkerton, Ontario

BACKGROUND

Post-infectious irritable bowel syndrome is a common clinical phenomenon of uncertain aetiology.

AIM

To test the association between intestinal permeability and irritable bowel syndrome symptoms 2 years after a large waterborne outbreak of bacterial gastroenteritis.

METHODS

Consecutive adults with Rome I irritable bowel syndrome and controls without irritable bowel syndrome attending a community clinic were enrolled. Intestinal permeability was measured as the ratio of fractional urinary excretions of lactulose and mannitol, and compared among cases vs. controls and predictors of abnormal intestinal permeability were assessed.

RESULTS

A total of 218 subjects (132 irritable bowel syndrome cases and 86 non-irritable bowel syndrome controls) completed the study protocol. About 27 (12%) had been diagnosed with the irritable bowel syndrome before the outbreak and 115 (53%) had been ill during the outbreak. Lactulose-mannitol ratios were increased among cases vs. controls (Mann-Whitney mean rank 118.8 vs. 95.3, P = 0.007), and cases were more likely to have a ratio >0.020 (P = 0.007). Among cases, those with increased intestinal permeability were more likely to report increased stool frequency. Both irritable bowel syndrome symptoms and male gender, but not diarrhoeal illness during the outbreak, were significant predictors of abnormal permeability.

CONCLUSIONS

Irritable bowel syndrome symptoms are associated with a subtle increase in intestinal permeability irrespective of prior gastroenteritis. This may improve understanding of the aetiology of both sporadic and post-infectious irritable bowel syndrome.

Epidemiological aspects of irritable bowel syndrome in Europe and North America

The epidemiology of irritable bowel syndrome (IBS) in Europe and North America was analyzed from published material. The percentage of the population of Western civilisation with IBS symptoms is between 10 and 15% in most studies. The proportion of a Western population visiting a doctor for IBS symptoms is around 5%. The prevalence of IBS and the proportion of consulters do not seem to depend on age in an adult population. The female-to-male ratio of IBS in the population is close to 2. It is higher in IBS consulters in primary care and may be as high as 3 or 4 in tertiary referral centers. At least in patients from these centers, the number of physician visits and colonoscopies is considerable. Most of the consulters get a drug prescription.

LDP-02 (Millenium)

Millennium (formerly LeukoSite) and Genentech are developing LDP-02, a humanized monoclonal antibody to the alpha4beta7 integrin receptor on leukocytes, for potential use in the treatment of inflammatory bowel diseases (IBD), such as Crohn's disease and ulcerative colitis [274580]. LeukoSite intended to develop iv and sc formulations of LDP-02 for acute IBD [315156]. In December 1997, Genentech entered into a collaboration with LeukoSite to develop and commercialize LDP-02 for the treatment of IBD [275395], [279420]. A phase II SBIR grant was awarded to LeukoSite in September 1996. The US $750,000 grant was used to develop LDP-02 and to conduct preclinical tests on the antibody for the treatment of IBD [218689]. In February 1999, Lehman Brothers predicted the drug had a 10% probability of reaching market. Assuming a successful launch, Lehman Brothers analysts estimated peak sales would occur in 2011 with sales at that time of US $250 million [319225].

Incremental cost-effectiveness analysis comparing rofecoxib with nonselective NSAIDs in osteoarthritis: Ontario Ministry of Health perspective

BACKGROUND

Clinical trials have shown rofecoxib, a selective inhibitor of cyclo-oxygenase-2, to be associated with fewer gastrointestinal complications than non-selective nonsteroidal anti-inflammatory drugs (NSAIDs).

OBJECTIVE

To evaluate the potential clinical and economic consequences of rofecoxib prescription in Ontario, Canada, for patients with osteoarthritis (OA) aged >65 years who did not respond to paracetamol (acetaminophen) therapy.

DESIGN

Decision analytic modelling study.

METHODS

A model was constructed to compare rofecoxib and nonselective NSAIDs with respect to their gastrointestinal complications in patients with OA. The model had a 1-year horizon and considered direct medical costs from the perspective of the Ontario Ministry of Health. Event rates were estimated from a pooled analysis of 8 phase IIb/Ill clinical trials. The number of perforations, ulcers and bleeds (PUBs) with each strategy was used as the primary measure of effectiveness.

RESULTS

In the base-case scenario, the expected total cost per patient-day on nonselective NSAIDs was 1.60 Canadian dollars (Can dollars) versus 1.67 Can dollars on rofecoxib (1999 values). Rofecoxib was associated with 0.0109 fewer PUBs per patient per year. The incremental cost to avoid 1 additional PUB by substituting rofecoxib for nonselective NSAIDs was 2247 Can dollars. The rofecoxib strategy became dominant if a gastroprotective agent was prescribed to more than 27.5% of the patients receiving nonselective NSAIDs.

CONCLUSION

For patients with OA aged >65 years in whom paracetamol therapy has failed, rofecoxib may represent a cost-effective alternative to nonselective NSAIDs. Increased costs for drug acquisition are offset, in part. by avoidance of gastrointestinal complications and reduced use of gastroprotective agents. Rofecoxib may offer increased benefit among patients at a higher risk of serious gastrointestinal events.

Increased intestinal permeability precedes the onset of Crohn's disease in a subject with familial risk

Increased intestinal permeability to several specific molecular probes has been observed in patients with Crohn's disease and their first-degree relatives. A positive family history is also a potent risk factor for inflammatory bowel disease. Although it has been argued that increased permeability in relatives may confer an increased future risk of developing Crohn's disease, long-term follow-up of such family members has been lacking. We describe a 24-year-old woman with a positive family history of Crohn's disease who had an elevated gut permeability to (51)Cr-EDTA at age 13, as part of a cross-sectional cohort study in patients and their first-degree relatives. She was asymptomatic at the time, and extensive investigation found no evidence of microscopic or macroscopic Crohn's disease. Repeat investigation because of symptom onset at age 21 revealed ileocolonic Crohn's disease, which required treatment with systemic corticosteroids to induce a clinical remission. In this case, a permeability defect was clearly identified to precede the onset of Crohn's disease in a subject at increased risk. This observation provides support for the hypothesis that increased gut permeability to macromolecules is an early step in the pathogenesis of this disorder.

A randomized controlled trial to assess alendronate-associated injury of the upper gastrointestinal tract

BACKGROUND

Aminobisphosphonates are recommended for postmenopausal osteoporosis but have been associated with injury to the upper gastrointestinal tract.

AIM

To conduct a randomized controlled trial, to assess the endoscopic damage caused by alendronate and its effect on gastric mucosal prostaglandin synthesis.

METHODS

Seventy-six healthy volunteers age 40-60 years, with normal baseline endoscopy were randomly assigned to treatment with: (A) ASA 650 mg q. d.s.; (B) alendronate 10 mg o.d.; or (C) placebo o.d. for 14 days. Mucosal injury scores on day 14 of treatment were reported by a blinded endoscopist. Gastric biopsies were analysed for prostaglandin E2 (PGE2) concentration by radioimmunoassay.

RESULTS

Oesophageal injury did not differ among treatment groups. Gastric ulcers developed in five out of 26 subjects given ASA, two out of 25 given alendronate, and none of 25 given placebo. The mucosal damage scores for the alendronate group exceeded those for the placebo group in the gastric body but not at other sites. Injury scores for ASA exceeded those for placebo in the duodenum, antrum, body, and fundus. The mean change in log10[PGE2] (ng/mg protein) was - 0.07 for placebo, - 0.80 for ASA, and + 0.62 for alendronate (differences not significant).

CONCLUSIONS

Alendronate is associated with injury and ulceration of the gastric mucosa. This effect was not associated with any significant change in gastric mucosal PGE2 levels.

Putting rectal 5-aminosalicylic acid in its place: the role in distal ulcerative colitis

Oral aminosalicylates such as sulfasalazine and mesalamine are widely prescribed for the treatment of mild or moderately active distal ulcerative colitis. However, a critical review of the literature demonstrates that rectal 5-aminosalicylic acid (5-ASA) is the optimal therapy for this disease. Meta-analyses of published trials show that rectally delivered 5-ASA is superior to placebo and to conventional rectal corticosteroids in inducing remission of distal ulcerative colitis, whereas the combination of rectal 5-ASA with a rectal corticosteroid or oral aminosalicylate is superior to rectal 5-ASA alone. For maintaining remission of distal ulcerative colitis, rectal 5-ASA is significantly better than placebo and at least as effective as oral 5-ASA. The dosage forms available for rectal delivery include suppositories, foams, and liquid enemas, and selection among these preparations should be guided by the proximal extent of disease and patient preference. The efficacy of rectal 5-ASA is complemented by its low rate of reported adverse effects, which may reflect its reduced potential for systemic absorption. This review summarizes the evidence supporting the role of rectal 5-ASA as a first-line therapy for mild or moderately active distal ulcerative colitis, and offers guidelines for its use.

A critical approach to clinical practice guidelines

The rate of publication of clinical practice guidelines for the management of common medical illnesses continues to accelerate. The appropriate dissemination and uptake of high quality practice guidelines can synthesize evidence, improve patient outcomes and enhance the efficiency of health care delivery. However, the methodological rigour and relevance of the growing number of publications labelled 'clinical practice guidelines' vary widely. Health care payers, providers and advocates must learn to appraise and interpret guideline recommendations critically. A simple and practical nine-question approach to evaluating the quality, relevance and effectiveness of clinical practice guidelines is presented.

Test and treat strategies for Helicobacter pylori in uninvestigated dyspepsia: a Canadian economic analysis

BACKGROUND

Recognition of the pivotal role of Helicobacter pylori in the pathogenesis of peptic ulcer disease has revolutionized primary care approaches to dyspepsia. Decision analysis was used to compare the cost effectiveness of empirical ranitidine with a test and treat strategy using either H pylori serology or the 13carbon-urea breath test (13C-UBT).

PATIENTS AND METHODS

A cohort of patients under age 50 years presenting with uninvestigated dyspepsia was evaluated. Three initial strategies were compared with respect to direct medical costs and effectiveness in curing H pylori-related ulcers - empirical ranitidine, H pylori serology and UBT. A one-year time horizon and third-party payer perspective were adopted in a Canadian health care setting.

RESULTS

UBT was more costly than either serology or ranitidine but was the most effective strategy and required the fewest endoscopies. No strategy demonstrated dominance over another in the base case. The incremental cost effectiveness ratio (ICER) of serology versus ranitidine was $118/cure, and sensitivity analysis induced dominance of serology in several plausible scenarios. The baseline ICER of UBT versus serology was $885/cure but showed substantial variation in sensitivity analysis. Each ICER was highly sensitive to variation in the cost of the tests themselves. At a serology cost of $25, UBT became dominant when its cost fell to $39.

CONCLUSIONS

In low risk patients with uninvestigated dyspepsia, testing for H pylori using serology appears to be economically attractive. 13C-UBT may be a cost effective alternative to serology if local conditions closely approximate the model parameters. Future changes in the costs of serology and 13C-UBT may determine the optimal approach.

Obscure gastrointestinal bleeding: an approach to management

Obscure gastrointestinal bleeding provides an uncommon but frustrating and resource-intensive challenge for clinicians. Such patients hemorrhage recurrently from sites within the gastrointestinal tract that are not detected by routine endoscopy or radiography, and require a special diagnostic approach to localize or exclude less common bleeding sources such as small bowel angioectasia or neoplasia. The differential diagnosis of obscure gastrointestinal hemorrhage is discussed, and the performance of available endoscopic, radiological and surgical diagnostic tools including enteroscopy are examined critically. A stepwise management algorithm that progresses from the history and physical examination to surgical exploration is offered to facilitate early and efficient diagnosis.

Ilodecakin. Schering-Plough Corp

Schering-Plough's interleukin (IL)-10 (ilodecakin) is under investigation for the potential treatment of autoimmune diseases, solid tumors, ulcerative colitis, Crohn's disease and organ transplantation. In June 1996, ilodecakin entered phase II trials for Crohn's disease, ulcerative colitis and rheumatoid arthritis and, as of June 1999 was reported to be in phase III trials for Crohn's disease and rheumatoid arthritis. It has also demonstrated promising effects in the treatment of inflammatory bowel disease. In January 1997, phase I trials began in HIV-infected patients. Initial results from a pilot study, carried out by the National Institute of Allergy and Infectious Disease Control, indicated that a single dose of IL-10 decreases the blood viral load. The results, however, were transient. Early clinical studies are ongoing in acute lung injury, ischemia-reperfusion injury, multiple sclerosis and psoriasis. In February 1999, Morgan Stanley Dean Witter predicted sales of US $50 million in 2000 rising to US $325 million in 2005.

Demographic predictors of resource utilization for bleeding peptic ulcer disease: the Ontario GI Bleed Study

Peptic ulcer disease (PUD) and its complications impose a substantial burden on health care resources. To help identify subpopulations in which preventative measures might achieve maximal cost savings, the authors studied the variation in resource utilization and cost for management of bleeding PUD among demographic subgroups. Resource utilization profiles and direct medical cost estimates were generated for consecutive admissions for bleeding PUD at four hospitals in southern Ontario via chart review and adaptation of an administrative cost database. Multiple linear regression models were developed to identify independent demographic predictors of direct medical case cost and hospital length of stay (LOS). Among 158 admissions, the average LOS and case costs were 5.73 days and $2,953 (Canadian) respectively. Age, comorbid illness, nonsteroidal anti-inflammatory drug use, and the absence of prior PUD or upper gastrointestinal hemorrhage were associated with higher cost in univariate analysis, whereas increasing age and comorbidity predicted LOS. Only age and absence of prior PUD persisted as independent predictors of direct medical cost and LOS in a stepwise multiple linear regression. Costs for managing bleeding PUD vary substantially among demographic subgroups. More careful stratification of treatment costs is needed when economic models of interventions to prevent or to treat PUD are applied to specific subpopulations.

Prediction of resource utilization and case cost for acute nonvariceal upper gastrointestinal hemorrhage at a Canadian community hospital

OBJECTIVE

Upper gastrointestinal hemorrhage (UGIH) is common, and thus imposes a substantial burden on health care resources. We describe resource utilization and cost for management of acute nonvariceal UGIH, and studied their variation among population subgroups.

METHODS

Resource utilization and direct medical case costs were extracted for consecutive admissions for nonvariceal UGIH at a large community hospital in southern Ontario through chart review and adaptation of an administrative case cost database. Univariate and multiple regression models were then developed to identify independent demographic predictors of case cost and length of stay.

RESULTS

Among 116 eligible admissions the average length of stay and case cost were 4.26 days and Can$2690, respectively (Can$1 = US$0.70). Both cost and length of stay demonstrated significant univariate relationships with age, comorbid illness, prior peptic ulcer disease (PUD), and prior UGIH. Age and prior PUD persisted as independent predictors in multiple regression models. An inverse transformation of total case cost allowed these variables to explain 26% of the total variance.

CONCLUSIONS

Resource utilization for management of acute nonvariceal UGIH at a Canadian community hospital varies substantially among population subgroups, but correlates independently with age and prior ulcer history. Careful attention must be paid to practice environments and demographic profiles before economic models of strategies to prevent or treat UGIH are applied to specific subpopulations.

Terminal ileal imaging with ileoscopy versus small-bowel meal with pneumocolon

Disease of the terminal ileum can be diagnosed by ileocolonoscopy or barium radiography. We compared the diagnostic accuracy in the terminal ileum of ileocolonoscopy and small-bowel meal with pneumocolon. Consecutive patients during an 18-month period who had both ileocolonoscopy and small bowel meal with pneumocolon were identified and their colonoscopy reports, radiographs, and ileal biopsies reviewed blindly by paired gastroenterologists, radiologists, and pathologists, respectively. A gold-standard diagnosis was determined for each patient by consensus. Of 48 study subjects, 14 (29.2%) had Crohn's disease, 5 (10.4%) had lymphoid nodular hyperplasia, and 29 (60.4%) were normal. The sensitivity for a diagnosis of Crohn's ileitis was 92.9% for ileocolonoscopy and 100% for small-bowel meal, while their specificities were 100% and 97.1% respectively. The gold standard diagnosis confirmed ileocolonoscopic findings in 45 patients (93.8%) and radiographic findings in 42 patients (87.5%). Agreement between ileocolonoscopy and small bowel meal occurred in 39 cases (81.2%). By combining histology with ileocolonoscopy, the sensitivity and specificity could be increased to 100% for all diagnoses. Ileocolonoscopy and small-bowel meal with pneumocolon are complementary techniques for imaging the terminal ileum. A prospective comparative trial is now needed to more objectively assess their accuracy, cost effectiveness, and adverse effects.

Ketotifen treatment of active colitis in patients with 5-aminosalicylate intolerance

Mast cell stabilizers are commonly used in the treatment of asthma and allergic disorders. Although the role of mucosal mast cells in the pathogenesis of inflammatory bowel disease remains uncertain, mast cell stabilizers have been shown in animal models to attenuate the severity of experimental colitis. The authors' experience with ketotifen in three patients--one each with Crohn's disease, ulcerative colitis and collagenous colitis--who had demonstrated allergy to, or intolerance of, 5-aminosalicylic acid is reported.

Omeprazole for refractory gastroesophageal reflux disease during pregnancy and lactation

Symptomatic gastroesophageal reflux is a common complication of pregnancy and lactation. However, the safety of many effective medical therapies, including oral proton pump inhibitors, has not been well defined. The administration of oral omeprazole to a 41-year-old female during the third trimester of pregnancy, after ranitidine and cisapride failed to control her refractory gastroesophageal reflux, is reported. No adverse fetal effects were apparent, and the patient elected to continue omeprazole therapy (20 mg/day) while breastfeeding. Peak omeprazole concentrations in breast milk (58 nM, 3 h after ingestion) were less than 7% of the peak serum concentration (950 nM at 4 h), indicating minimal secretion. Although omeprazole is a potentially useful therapy for refractory gastroesophageal reflux during pregnancy and lactation, further data are needed to define better its safety and efficacy.

Successful therapy of refractory erythema nodosum associated with Crohn's disease using potassium iodide

Erythema nodosum is a common extraintestinal manifestation of Crohn's disease. While mild skin involvement often responds to conservative management, severe or refractory cases may require systemic corticosteroid or immunosuppressive therapy. This report describes successful treatment of severe, refractory erythema nodosum associated with Crohn's colitis using oral potassium iodide. While the mechanism of action of this agent is poorly understood, it appears to be an effective and nontoxic therapy for Crohn's-related erythema nodosum and warrants further evaluation in a placebo controlled trial.

Rectal corticosteroids versus alternative treatments in ulcerative colitis: a meta-analysis

BACKGROUND

Clear strategies to optimise the use of corticosteroids in ulcerative colitis are lacking.

AIM

A meta-analysis was undertaken to examine critically the role of rectal corticosteroids in the management of active distal ulcerative colitis.

METHODS

All reported randomised controlled trials were retrieved by searching the Medline and EMBASE databases and the bibliographies of relevant studies. Trials which met inclusion criteria were assessed for scientific rigour. Data were extracted by two independent observers according to predetermined criteria.

RESULTS

Of 83 trials retrieved, 33 met inclusion criteria. Pooled odds ratios (POR) showed conventional rectal corticosteroids and rectal budesonide to be clearly superior to placebo. In seven trials, rectal 5-aminosalicylic acid (5-ASA) was significantly better than conventional rectal corticosteroids for inducing remission of symptoms, endoscopy, and histology with POR of 2.42 (95% confidence interval (CI) 1.72-3.41), 1.89 (95% CI 1.29-2.76), and 2.03 (95% CI 1.28-3.20), respectively. Rectal budesonide was of comparable efficacy to conventional corticosteroids but produced less endogenous cortisol suppression. Side effects, although inconsistently reported, were generally minor. A cost comparison of rectal preparations showed 5-ASA to be less expensive than corticosteroids.

CONCLUSIONS

Rectal 5-ASA is superior to rectal corticosteroids in the management of distal ulcerative colitis.

Hormonal therapy for bleeding gastrointestinal mucosal vascular abnormalities: a promising alternative

Recurrent bleeding from an obscure gastrointestinal source is a common but often frustrating clinical challenge. Frequently these bleeds can be attributed to vascular anomalies in the upper or lower gastrointestinal tract. Traditional management has included surgical resection and endoscopic fulguration. However, these methods are often ineffective when vascular lesions are diffuse, difficult to identify, or endoscopically inaccessible. Hormone therapy with a combination of oestrogen and progesterone represents a promising alternative. Since initial reports of success in patients with epistaxis from hereditary haemorrhagic telangiectasia, growing evidence supports its role in reducing bleeding from gastrointestinal vascular anomalies. Existing literature is critically reviewed and management strategies incorporating hormone therapy are suggested.

Rectal aminosalicylate therapy for distal ulcerative colitis: a meta-analysis

BACKGROUND

To summarize and quantify the evidence supporting rectal 5- or 4-aminosalicylate (ASA) therapies for disease exacerbation or remission maintenance in distal ulcerative colitis, we performed a meta-analysis.

METHODS

All randomized, double-blind controlled trials involving aminosalicylate therapy were retrieved from a MEDLINE search, review articles on ulcerative colitis therapy or their bibliographies. Of 55 studies retrieved, 19 met the inclusion criteria. Appraisal and data extraction were performed by two observers and scoring disagreements were resolved by consensus.

RESULTS

Eleven trials tested 5-ASA and three tested 4-ASA in active ulcerative colitis. 5-ASA was superior to placebo for inducing remission or symptomatic improvement in active ulcerative colitis with a pooled odds ratio of 7.36 (95% Confidence interval (CI): 4.72-11.47). In four trials the pooled odds ratio for endoscopic improvement was 10.04 (95% CI: 5.72-17.61) and for histological improvement 10.31 (95% CI: 5.85-18.18). Studies evaluating 4-ASA suggest a benefit similar to prednisolone in treating active disease. Five trials assessed remission maintenance with 5-ASA, and when compared to placebo gave a pooled odds ratio of 16.22 (95% CI: 4.71-55.92). No dose-response relationship was observed. ASA compounds were not therapeutically superior to other treatments.

CONCLUSIONS

We conclude that rectal 5-ASA is effective therapy for active distal ulcerative colitis. More trials are needed to assess 4-ASA, dose-response effects and the ideal regimen for remission maintenance.

Fluid production by in vitro lungs from fetal guinea pigs

Lungs from fetal guinea pigs (54-67 days of gestation) were supported in vitro, and lung liquid secretion rates were measured by a dye-dilution technique. The average secretion rate in the first hour was 2.14 +/- 0.08 (SE) mL x kg-1 body weight.h-1 (0.21 +/- 0.01 mL/h) (n = 450); this was comparable to intact preparations. In an independent study of 30 lungs, secretion continued unchanged for 3 h, with no significant change in fluid composition. Between 54 days and term, production appeared to fall in terms of millilitres per kilogram per hour. The following agents were placed in the supporting saline during the middle hour of incubation. (i) Sodium iodoacetate: at 10(-4) M this produced a fall in secretion (fall, succeeding hours; 55.4 +/- 23.0 and 64.9 +/- 17.5%; n = 6); at 10(-3) M it stopped secretion (fall, succeeding hours; 87.2 +/- 10.3 and 100%, n = 6). (ii) Ouabain: at 10(-5) M there was no change in production (n = 6); at 10(-4) M, four preparations were unaffected, two reduced production. (iii) Epinephrine (10(-7) M) produced a significant fall in production in all cases (n = 6); in four preparations secretion reduced (average fall, 64.4 +/- 10.8%); in two preparations there was reabsorption (average rate, -1.03 mL.kg-1.h-1). This extends the effect of epinephrine to the guinea pig, and suggests that the in vitro preparation is a useful model for studies of the fetal lung.

The spontaneously diabetic BB Wistar rat. Morphologic and physiologic studies of peripheral nerve

The spontaneously diabetic "BB" Wistar rat was examined for evidence of peripheral nerve abnormalities by a combined morphologic and physiologic approach. The studies were done on rats kept severely hyperglycemic and frequently ketotic. The peripheral nerves of the lower extremities, including the most distal nerves of the intrinsic foot muscles, revealed only minimal abnormalities by histologic and morphometric examination. Sciatic nerve conduction studies, however, measured over a 2-month period did not show a significant slowing in diabetics compared with age-matched controls, as well as between diabetics and weight-matched controls. In addition, fast anterograde axoplasmic transport studies were correlated with serum glucose results. Rats maintained severely hyperglycemic with or without ketosis had abnormal down flow rats of [3H]leucine compared to controls. Diabetic rats maintained with normal blood glucose levels showed no change in transport rates. These results suggested that persistent hyperglycemia in the "BB" Wistar rat produces significant physiologic but not significant structural abnormalities in the peripheral nerve.