Anna M. Forsberg

Prevalence of colonic neoplasia and advanced lesions in the normal population : a prospective population-based colonoscopy study.

Abstract Objective. There are few prospective studies of the prevalence of colonic neoplasia in the normal population. In order to properly evaluate screening-protocols for colorectal cancer in risk groups (e.g., older subjects or those with a family history), it is essential to know the prevalence of adenomas and cancer in the normal population. Methods. A prospective population-based colonoscopy study on 745 individuals born in Sweden aged 19–70 years was conducted (mean age 51.1 years). All polyps seen were retrieved and examined. Results. Out of the 745 individuals 27% had polyps, regardless of kind. Adenomas were found in 10% of the individuals and finding of adenomas was positively correlated to higher age. Men had adenomas in 15% and women in 6% of the cases. Women had a right-sided dominance of adenomas. Hyperplastic polyps were seen in 21% of the individuals. The presence of hyperplastic polyps was significantly positively correlated to the presence of adenomas. Advanced adenomas were seen in 2.8% of the study participants, but no cancers were detected. Conclusion. One in 10 healthy subjects had an adenoma but advanced adenomas were uncommon. Men and women have a different adenoma prevalence and localization. The results provide baseline European data for evaluating colonoscopy screening-protocols for colorectal cancer risk groups, and the findings may have implications for colon cancer screening in the normal, otherwise-healthy population.

A pooled analysis of the outcome of prospective colonoscopic surveillance for familial colorectal cancer

Surveillance guidelines for the management of familial colorectal cancer (FCC), a dominant family history of colorectal cancer in which the polyposis syndromes and Lynch syndrome have been excluded, are not firmly established. The outcome of colonoscopic surveillance is studied using data from six centers. DNA mismatch repair deficiency was excluded by genetic testing. Families were classified as FCC type X if they fulfilled the original Amsterdam criteria (AC) and late onset (LOFCC) if they fulfilled the AC apart from not having a cancer aged under 50. The most advanced findings on colonoscopy were analyzed. One thousand five hundred eighty‐five individuals (median age 47.3, 44% male) from 530 FCC families (349 FCC type X) underwent a total of 4,992 colonoscopies with 7,904 patient‐years of follow‐up. Results for FCC type X and LOFCC were very similar. At baseline, 22 prevalent asymptomatic colorectal cancers were diagnosed, 120 (7.6%) individuals had high‐risk adenomas and 225 (14.2%) simple adenomas. One thousand eighty‐eight individuals had a further colonoscopy (median follow‐up of 6.2 years). Of nine individuals diagnosed with cancer, eight had a previous history of at least one polyp/adenoma. High‐risk adenomas were detected in 92 (8.7%) and multiple adenomas were detected in 20 (1.9%) individuals. Both FCC type X and LOFCC have a high prevalence of colorectal cancers and on follow‐up develop high‐risk adenomas (including multiple adenomas), but infrequent interval cancers. They should be managed similarly with five‐yearly colonoscopies undertaken from between 30 and 40 with more intensive surveillance in individuals developing multiple or high‐risk adenomas.

Towards a healthy stomach? Helicobacter pylori prevalence has dramatically decreased over 23 years in adults in a Swedish community

Background In Western countries the prevalence of Helicobacter pylori (H. pylori) infection may be declining but there is a lack of recent longitudinal population studies. We evaluated the changing epidemiology over a 23-year period in Sweden. Materials and methods In 1989, the validated Abdominal Symptom Questionnaire (ASQ) was mailed to a random sample of inhabitants (ages 22–80 years) in a Swedish community, and 1097 (87%) responded. H. pylori serology was analysed in a representative subsample (n = 145). Twenty-three years later, the ASQ was mailed again using similar selection criteria, and 388 out of 1036 responders had an upper endoscopy with assessment of H. pylori and corpus atrophy status. Results The prevalence of positive H. pylori serology decreased from 37.9% (1989) to 15.8% (2012), corresponding to a decrease in odds of 75% per decade (odds ratio (OR): 0.25; 95% confidence interval (CI): 0.11–0.59, p = 0.001) independent of age, gender, body mass index (BMI) and level of education, with a pattern consistent with a birth cohort effect. The prevalence increased with increasing age (p = 0.001). The prevalence of H. pylori on histology in 2012 was 11.4% (95% CI 8.6–15.0). The prevalence of corpus atrophy on serology and/or histology in 2012 was 3.2% (95% CI 1.8–5.5); all cases were ≥57 years old. Conclusion The stomach is healthier in 2012 compared with 1989. H. pylori prevalence in adults has decreased over the last two decades to a level where clinical management might be affected.

Hill classification is superior to the axial length of a hiatal hernia for assessment of the mechanical anti-reflux barrier at the gastroesophageal junction

Background and study aims: The pathogenesis of gastroesophageal reflux disease (GERD) is multifactorial, including the mechanical anti-reflux barrier of the gastroesophageal junction. This barrier can be evaluated endoscopically in two ways: by measuring the axial length of any hiatal hernia present or by assessing the gastroesophageal flap valve. The endoscopic measurement of axial length is troublesome because of the physiological dynamics in the area. Grading the gastroesophageal flap valve is easier and has proven reproducible. The aim of the present study was to compare the two endoscopic grading methods with regard to associations with GERD. Patients and methods: Population-based subjects underwent endoscopic examination assessing the axial length of hiatus hernia, the gastroesophageal flap valve using the Hill classification, esophagitis using the Los Angeles (LA) classification, and columnar metaplasia using the Z-line appearance (ZAP) classification. Biopsies were taken from the squamocolumnar junction to assess the presence of intestinal metaplasia. Symptoms were recorded with the validated Abdominal Symptom Questionnaire. GERD was defined according to the Montreal definition. Results: In total, 334 subjects were included in the study and underwent endoscopy; 86 subjects suffered from GERD and 211 presented no symptoms or signs of GERD. Based on logistic regression, the estimated area under the curve statistic (AUC) for Hill (0.65 [95 %CI 0.59 – 0.72]) was higher than the corresponding estimate for the axial length of a hiatal hernia (0.61 [95 %CI 0.54 – 0.68]), although the difference was not statistically significant (P = 0.225). Conclusion: From our data, and in terms of association with GERD, the Hill classification was slightly stronger compared to the axial length of a hiatal hernia, but we could not verify that the Hill classification was superior as a predictor. The Hill classification may replace the axial length of a hiatal hernia in the endoscopic assessment of the mechanical anti-reflux barrier of the gastroesophageal junction.

World Endoscopy Organization Consensus Statements on Post-Colonoscopy and Post-Imaging Colorectal Cancer

BACKGROUND & AIMS Colonoscopy examination does not always detect colorectal cancer (CRC)- some patients develop CRC after negative findings from an examination. When this occurs before the next recommended examination, it is called interval cancer. From a colonoscopy quality assurance perspective, that term is too restrictive, so the term post-colonoscopy colorectal cancer (PCCRC) was created in 2010. However, PCCRC definitions and methods for calculating rates vary among studies, making it impossible to compare results. We aimed to standardize the terminology, identification, analysis, and reporting of PCCRCs and CRCs detected after other whole-colon imaging evaluations (post-imaging colorectal cancers [PICRCs]). METHODS A 20-member international team of gastroenterologists, pathologists, and epidemiologists; a radiologist; and a non-medical professional met to formulate a series of recommendations, standardize definitions and categories (to align with interval cancer terminology), develop an algorithm to determine most-plausible etiologies, and develop standardized methodology to calculate rates of PCCRC and PICRC. The team followed the Appraisal of Guidelines for Research and Evaluation II tool. A literature review provided 401 articles to support proposed statements; evidence was rated using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. The statements were voted on anonymously by team members, using a modified Delphi approach. RESULTS The team produced 21 statements that provide comprehensive guidance on PCCRCs and PICRCs. The statements present standardized definitions and terms, as well as methods for qualitative review, determination of etiology, calculation of PCCRC rates, and non-colonoscopic imaging of the colon. CONCLUSIONS A 20-member international team has provided standardized methods for analysis of etiologies of PCCRCs and PICRCs and defines its use as a quality indicator. The team provides recommendations for clinicians, organizations, researchers, policy makers, and patients.

A register-based study: adverse events in colonoscopies performed in Sweden 2001–2013

Abstract Objectives: The rates for colonoscopy-associated adverse events vary considerably worldwide. In Sweden, the figures are known to a limited extent. We assessed the frequency of severe colonoscopy-related adverse events and the impacts of different risk factors, including the use of general anaesthesia. Material and methods: This is a retrospective population-based cohort study of the colonoscopies performed during the years 2001–2013 on adults identified in the Swedish health registers. The rates for bleeding, perforation, splenic injury and 30-day mortality were calculated. Covariates for risks were assessed in a multivariate Poisson regression model. Results: There were 593,315 colonoscopies performed on the 426,560 individuals included in the study. The rates for colonoscopy-related bleeding and perforation were 0.17% and 0.11%, respectively. When polypectomy was performed, the rates were 0.53% for bleeding and 0.25% for perforation. There were 31 splenic injuries (1:20,000 colonoscopies) reported. The crude 30-day death rate for colonoscopy was 0.68%. Of those diagnosed with bleeding or perforation, 5.6% and 6.1% were dead within 30 days, respectively. The multivariate RR for perforation when general anaesthesia was employed was 2.65 (p < .001; 95%CI 1.71–4.12). Conclusions: The perforation rate seemed to be relatively high in an international perspective. General anaesthesia was associated with a significantly higher risk for perforation. Splenic injuries were more frequent than expected.

Colonoscopy findings in high-risk individuals compared to an average-risk control population

Abstract Background and aims: There is clear evidence of reduced morbidity and mortality from regular colonoscopy programs in patients with Lynch syndrome (LS). Today, also individuals with empirically increased risks of colorectal cancer (CRC) are offered colonoscopic surveillance. The aim was to compare the findings at the first screening colonoscopy in LS carriers, and individuals with an increased risk of bowel cancer due to family history of CRC with a control population. Methods: Altogether 1397 individuals with an increased risk for CRC were divided in four risk groups: one with LS carriers and three groups with individuals with different family history of CRC. The findings were compared between the different risk groups and a control group consisting of 745 individuals from a control population who took part in a population-based colonoscopy study. Results: In LS, 30% of the individuals had adenomas and 10% advanced adenomas. The corresponding figures in the other risk groups were 14–24% and 4–7%, compared with 10% and 3% in the control group. The relative risk of having adenomas and advanced adenomas was, compared to controls, significantly higher for all risk groups except the group with the lowest risk. Age was a strong predictor for adenomas and advanced adenomas in both risk individuals and controls. Conclusions: Individuals with a family history of CRC have a high prevalence and cumulative risk of adenomas and advanced adenomas, and screening is motivated also in this risk group.

Identifying clinically relevant sliding hiatal hernias : a population-based endoscopy study

Abstract Objectives: The clinical relevance of small to moderate sliding hiatal hernias is controversial. The aims of the present study were to (1) investigate which symptoms are associated with sliding hiatal hernias and (2) define the length of a sliding hiatal hernia at which gastrointestinal symptoms occur. Methods: A study population representative of the general Swedish population answered a questionnaire regarding gastrointestinal symptoms and was investigated with an upper endoscopy. The length of any sliding hiatal hernia was measured. Results: Only reflux-related symptoms were associated with length of the hiatal hernia (acid regurgitation OR 1.46, CI 1.19–1.79, heartburn OR 1.27, CI 1.05–1.54), and the association did not become significant until an axial hiatal hernia length of 2 cm. Conclusions: Only reflux symptoms could be attributed to sliding hiatal hernias. Hiatal hernias less than 2 cm should be considered clinically insignificant.

Post-colonoscopy colorectal cancers in Sweden: room for quality improvement

Objective Post-colonoscopy colorectal cancer (PCCRC), a cancer occurring within a short interval of a colonoscopy, might be partly explained as missed or incompletely resected lesions. Associated risk factors are age, sex, comorbidity, cancer location, and colonoscopy volume. There is a gap in the knowledge of prevalence of PCCRC and the impact of different risk factors in Sweden. Methods This is a retrospective population-based observational cohort study of the colonoscopies performed on adults during the years 2001–2010 that were identified from Swedish health registers. The rate of PCCRC (diagnosed 6–36 months after the first colonoscopy) was defined as the number of PCCRCs divided by the number of colorectal cancers (CRC) in the interval of 0–36 months. Univariate and multivariate Poisson regression analyses examined associations with PCCRC. Results There were 289 729 colonoscopies performed on 249 079 individuals included in the study. There were 16 319 individuals with a colorectal cancer diagnosis 0–36 months after a colonoscopy. Of these, 1286 (7.9%) were PCCRCs. In the multivariate analysis, young age (18–30 years) and former polyp diagnosis had the highest risks [relative risk (RR)=3.3; 95% confidence interval: 2.1–5.2 and RR=3.1; 95% confidence interval: 2.7–3.6]. The impact of other risk factors, such as female sex, comorbidity, right sided colorectal cancer location, and time period, was consistent with the finding in other studies. Conclusion The prevalence of PCCRC in Sweden seems to be relatively high, indicating that there is room for improvement in colonoscopy quality. The high RR of PCCRC in the youngest age group, even though there were only a few cases, has not been described in other studies.