Steven J. Heitman

Prevalence of Adenomas and Colorectal Cancer in Average Risk Individuals: A Systematic Review and Meta-analysis

BACKGROUND & AIMS There is an extensive yet inconsistent body of literature reporting on the prevalence of adenomatous polyps (adenomas) and colorectal cancer among average risk individuals. The objectives of our study were to determine the pooled prevalence of adenomas and colorectal cancer, as well as nonadvanced and advanced adenomas, among average risk North Americans. METHODS Articles were obtained by searching electronic databases (MEDLINE: 1950 through March 2008 and EMBASE: 1980 through March 2008), bibliographies, major journals, and conference proceedings, with no language restrictions. Two reviewers independently selected cross-sectional studies reporting adenoma and colorectal cancer prevalence rates in average risk individuals and assessed studies for inclusion and quality, and extracted the data for analysis. Pooled adenoma and colorectal cancer prevalence rates were estimated using fixed and random effects models. Stratification and metaregression was used to assess heterogeneity. RESULTS Based on 18 included studies, the pooled prevalence of adenomas, colorectal cancer, nonadvanced adenomas, and advanced adenomas was 30.2%, 0.3%, 17.7%, and 5.7%, respectively. Heterogeneity was observed in the pooled prevalence rates for overall adenomas, advanced adenomas, and colorectal cancer and was explained by the mean age (> or = 65 years vs < 65 years) with older cohorts reporting higher prevalence rates. None of the study quality indicators was found to be significant predictors of heterogeneity. CONCLUSIONS The high prevalence of advanced adenomas and colorectal cancer, especially among older screen-eligible individuals, provides impetus for expanding colorectal cancer screening programs. Furthermore, the pooled prevalence estimates can be used as quality indicators for established programs.

Colorectal Cancer Screening for Average-Risk North Americans: An Economic Evaluation

An economic analysis of different screening methods for detection of colorectal cancers suggests that in US or Canadian settings, screening with fecal immunochemical testing results in lower health-care costs as compared with other screening approaches.

Cost-effectiveness of computerized tomographic colonography versus colonoscopy for colorectal cancer screening

Background: Computerized tomographic (CT) colonography is a potential alternative to colonoscopy for colorectal cancer screening. Its main advantage, a better safety profile, may be offset by its limitations: lower sensitivity, need for colonoscopy in cases where results are positive, and expense. Methods: We performed an economic evaluation, using decision analysis, to compare CT colonography with colonoscopy for colorectal cancer screening in patients over 50 years of age. Three-year outcomes included number of colonoscopies, perforations and adenomas removed; deaths from perforation and from colorectal cancer from missed adenomas; and direct health care costs. The expected prevalence of adenomas, test performance characteristics of CT colonography and colonoscopy, and probability of colonoscopy complications and cancer from missed adenomas were derived from the literature. Costs were determined in detail locally. Results: Using the base-case assumptions, a strategy of CT colonography for colorectal cancer screening would cost

Obstructive sleep apnoea is associated with diabetes in sleepy subjects

2.27 million extra per 100 000 patients screened; 3.78 perforation-related deaths would be avoided, but 4.11 extra deaths would occur from missed adenomas. Because screening with CT colonography would cost more and result in more deaths overall compared with colonoscopy, the latter remained the dominant strategy. Our results were sensitive to CT colonographys test performance characteristics, the malignant risk of missed adenomas, the risk of perforation and related death, the procedural costs and differences in screening adherence. Interpretation: At present, CT colonography cannot be recommended as a primary means of population-based colorectal cancer screening in Canada.

Effect of ambient air pollution on the incidence of appendicitis

Background: Although obstructive sleep apnoea (OSA) has been linked to insulin resistance and glucose intolerance, it is unclear whether there is an independent association between OSA and diabetes mellitus (DM) and whether all patients with OSA are at risk. The objective of this study was to determine the association between OSA and DM in a large cohort of patients referred for sleep diagnostic testing. Methods: A cross-sectional analysis of participants in a clinic-based study was conducted between July 2005 and August 2007. DM was defined by self-report and concurrent use of diabetic medications (oral hypoglycaemics and/or insulin). Sensitivity analysis was performed using a validated administrative definition of diabetes. OSA was defined by the respiratory disturbance index (RDI) using polysomnography or ambulatory monitoring. Severe OSA was defined as an RDI ⩾30/h. Subjective sleepiness was defined as an Epworth Sleepiness Scale score ⩾10. Results: Complete data were available for 2149 patients. The prevalence of DM increased with increasing OSA severity (p<0.001). Severe OSA was associated with DM following adjustment for patient demographics, weight and neck circumference (odds ratio (OR) 2.18; 95% CI 1.22 to 3.89; p<0.01). Following a stratified analysis, this relationship was observed exclusively in sleepy patients (OR 2.59 (95% CI 1.35 to 4.97) vs 1.16 (95% CI 0.31 to 4.37) in non-sleepy patients). Conclusions: Severe OSA is independently associated with DM in patients who report excessive sleepiness. Future studies investigating the impact of OSA treatment on DM may wish to focus on this patient population.

Liver Stiffness by Transient Elastography Predicts Liver-Related Complications and Mortality in Patients with Chronic Liver Disease

Background: The pathogenesis of appendicitis is unclear. We evaluated whether exposure to air pollution was associated with an increased incidence of appendicitis. Methods: We identified 5191 adults who had been admitted to hospital with appendicitis between Apr. 1, 1999, and Dec. 31, 2006. The air pollutants studied were ozone, nitrogen dioxide, sulfur dioxide, carbon monoxide, and suspended particulate matter of less than 10 μ and less than 2.5 μ in diameter. We estimated the odds of appendicitis relative to short-term increases in concentrations of selected pollutants, alone and in combination, after controlling for temperature and relative humidity as well as the effects of age, sex and season. Results: An increase in the interquartile range of the 5-day average of ozone was associated with appendicitis (odds ratio [OR] 1.14, 95% confidence interval [CI] 1.03–1.25). In summer (July–August), the effects were most pronounced for ozone (OR 1.32, 95% CI 1.10–1.57), sulfur dioxide (OR 1.30, 95% CI 1.03–1.63), nitrogen dioxide (OR 1.76, 95% CI 1.20–2.58), carbon monoxide (OR 1.35, 95% CI 1.01–1.80) and particulate matter less than 10 μ in diameter (OR 1.20, 95% CI 1.05–1.38). We observed a significant effect of the air pollutants in the summer months among men but not among women (e.g., OR for increase in the 5-day average of nitrogen dioxide 2.05, 95% CI 1.21–3.47, among men and 1.48, 95% CI 0.85–2.59, among women). The double-pollutant model of exposure to ozone and nitrogen dioxide in the summer months was associated with attenuation of the effects of ozone (OR 1.22, 95% CI 1.01–1.48) and nitrogen dioxide (OR 1.48, 95% CI 0.97–2.24). Interpretation: Our findings suggest that some cases of appendicitis may be triggered by short-term exposure to air pollution. If these findings are confirmed, measures to improve air quality may help to decrease rates of appendicitis.

Clinical Practice Guidelines for the Use of Video Capsule Endoscopy

Background Liver stiffness measurement (LSM) by transient elastography (TE, FibroScan) is a validated method for noninvasively staging liver fibrosis. Most hepatic complications occur in patients with advanced fibrosis. Our objective was to determine the ability of LSM by TE to predict hepatic complications and mortality in a large cohort of patients with chronic liver disease. Methods In consecutive adults who underwent LSM by TE between July 2008 and June 2011, we used Cox regression to determine the independent association between liver stiffness and death or hepatic complications (decompensation, hepatocellular carcinoma, and liver transplantation). The performance of LSM to predict complications was determined using the c-statistic. Results Among 2,052 patients (median age 51 years, 65% with hepatitis B or C), 87 patients (4.2%) died or developed a hepatic complication during a median follow-up period of 15.6 months (interquartile range, 11.0–23.5 months). Patients with complications had higher median liver stiffness than those without complications (13.5 vs. 6.0 kPa; P<0.00005). The 2-year incidence rates of death or hepatic complications were 2.6%, 9%, 19%, and 34% in patients with liver stiffness <10, 10–19.9, 20–39.9, and ≥40 kPa, respectively (P<0.00005). After adjustment for potential confounders, liver stiffness by TE was an independent predictor of complications (hazard ratio [HR] 1.05 per kPa; 95% confidence interval [CI] 1.03–1.06). The c-statistic of liver-stiffness for predicting complications was 0.80 (95% CI 0.75–0.85). A liver stiffness below 20 kPa effectively excluded complications (specificity 93%, negative predictive value 97%); however, the positive predictive value of higher results was sub-optimal (20%). Conclusions Liver stiffness by TE accurately predicts the risk of death or hepatic complications in patients with chronic liver disease. TE may facilitate the estimation of prognosis and guide management of these patients.

Population-based analysis of practices and costs of surveillance for colonic dysplasia in patients with primary sclerosing cholangitis and colitis

BACKGROUND & AIMS Video capsule endoscopy (CE) provides a noninvasive option to assess the small intestine, but its use with respect to endoscopic procedures and cross-sectional imaging varies widely. The aim of this consensus was to provide guidance on the appropriate use of CE in clinical practice. METHODS A systematic literature search identified studies on the use of CE in patients with Crohns disease, celiac disease, gastrointestinal bleeding, and anemia. The quality of evidence and strength of recommendations were rated using the Grading of Recommendation Assessment, Development, and Evaluation (GRADE) approach. RESULTS The consensus includes 21 statements focused on the use of small-bowel CE and colon capsule endoscopy. CE was recommended for patients with suspected, known, or relapsed Crohns disease when ileocolonoscopy and imaging studies were negative if it was imperative to know whether active Crohns disease was present in the small bowel. It was not recommended in patients with chronic abdominal pain or diarrhea, in whom there was no evidence of abnormal biomarkers typically associated with Crohns disease. CE was recommended to assess patients with celiac disease who have unexplained symptoms despite appropriate treatment, but not to make the diagnosis. In patients with overt gastrointestinal bleeding, and negative findings on esophagogastroduodenoscopy and colonoscopy, CE should be performed as soon as possible. CE was recommended only in selected patients with unexplained, mild, chronic iron-deficiency anemia. CE was suggested for surveillance in patients with polyposis syndromes or other small-bowel cancers, who required small-bowel studies. Colon capsule endoscopy should not be substituted routinely for colonoscopy. Patients should be made aware of the potential risks of CE including a failed procedure, capsule retention, or a missed lesion. Finally, standardized criteria for training and reporting in CE should be defined. CONCLUSIONS CE generally should be considered a complementary test in patients with gastrointestinal bleeding, Crohns disease, or celiac disease, who have had negative or inconclusive endoscopic or imaging studies.

Decreasing mortality from acute biliary diseases that require endoscopic retrograde cholangiopancreatography: a nationwide cohort study.

Background: Patients with primary sclerosing cholangitis (PSC) and colitis are at risk of developing dysplasia and colorectal cancer (CRC). Consequently, annual surveillance colonoscopy with random biopsies is recommended. The aims of the present study were (1) to determine the incidence of dysplasia or CRC, (2) to assess surveillance practices, and (3) to assess the costs associated with surveillance of PSC patients. Methods: A population‐based study was conducted between 2000 and 2004 to identify all patients with a diagnosis of PSC using regional databases. Colonic histopathology reports of PSC patients with colitis were reviewed to determine the frequency of surveillance colonoscopies performed between 2000 and 2005, the number of biopsies retrieved, and the presence of CRC or dysplasia. The cost of annual surveillance colonoscopy with 33 random biopsies to detect 1 additional case of dysplasia was calculated from a local costs database. Results: Forty‐five PSC patients with ulcerative colitis or Crohns disease were identified. Five patients (11.1%) were diagnosed with low‐grade dysplasia (n = 2), dysplasia‐associated lesion or mass (n = 2), or CRC (n = 1) during the 5‐year follow‐up period for an incidence rate of 3.1 events per 100 person‐years (95% confidence interval: 1.0–7.2/100 person‐years). Two of these lesions were detected through surveillance and 3 because of symptomatic presentation. Only 36% (56) of the expected number of surveillance colonoscopies were performed. The median number of biopsies collected was 27 (IQR: 19–33). The cost of surveillance to detect 1 additional case of dysplasia was

The Feasibility and Reliability of Transient Elastography Using Fibroscan®: A Practice Audit of 2335 Examinations

26,495. Conclusion: Despite a high rate of colorectal dysplasia or CRC among PSC patients, surveillance was suboptimal.