Development and Validation of the Asia-Pacific Proximal Colon Neoplasia Risk Score.

BACKGROUND & AIMS: Patients found to be at high risk of advanced proximal neoplasia (APN) after flexible sigmoidoscopy screening should be considered for colonoscopy examination. We developed and validated a scoring system to identify persons at risk for APN. METHODS: We collected data from 7954 asymptomatic subjects (age, 50-75 y) who received screening colonoscopy examinations at 14 sites in Asia. We randomly assigned 5303 subjects to the derivation cohort and the remaining 2651 to the validation cohort. We collected data from the derivation cohort on age, sex, family history of colorectal cancer, smoking, drinking, body mass index, medical conditions, and use of nonsteroidal anti-inflammatory drugs or aspirin. Associations between the colonoscopic findings of APN and each risk factor were examined using the Pearson χ2 test, and we assigned each participant a risk score (0-15), with scores of 0 to 3 as average risk and scores of 4 or higher as high risk. The scoring system was tested in the validation cohort. We used the Cochran-Armitage test of trend to compare the prevalence of APN among subjects in each group. RESULTS: In the validation cohort, 79.5% of patients were classified as average risk and 20.5% were classified as high risk. The prevalence of APN in the average-risk group was 1.9% and in the high-risk group was 9.4% (adjusted relative risk, 5.08; 95% CI, 3.38-7.62; P < .001). The score included age (61-70 y, 3; ≥70 y, 4), smoking habits (current/past, 2), family history of colorectal cancer (present in a first-degree relative, 2), and the presence of neoplasia in the distal colorectum (nonadvanced adenoma 5-9 mm, 2; advanced neoplasia, 7). The c-statistic of the score was 0.74 (95% CI, 0.68-0.79), and for distal findings alone was 0.67 (95% CI, 0.60-0.74). The Hosmer-Lemeshow goodness-of-fit test statistic was greater than 0.05, indicating the reliability of the validation set. The number needed to refer was 11 (95% CI, 10-13), and the number needed to screen was 15 (95% CI, 12-17). CONCLUSIONS: We developed and validated a scoring system to identify persons at risk for APN. Screening participants who undergo flexible sigmoidoscopy screening with a score of 4 points or higher should undergo colonoscopy evaluation.

Population Density and Risk of Inflammatory Bowel Disease: A Prospective Population-Based Study in 13 Countries or Regions in Asia-Pacific.

INTRODUCTION: Living in an urban environment may increase the risk of developing inflammatory bowel disease (IBD). It is unclear if this observation is seen globally. We conducted a population-based study to assess the relationship between urbanization and incidence of IBD in the Asia-Pacific region. METHODS: Newly diagnosed IBD cases between 2011 and 2013 from 13 countries or regions in Asia-Pacific were included. Incidence was calculated with 95% confidence interval (CI) and pooled using random-effects model. Meta-regression analysis was used to assess incidence rates and their association with population density, latitude, and longitude. RESULTS: We identified 1175 ulcerative colitis (UC), 656 Crohn's disease (CD), and 37 IBD undetermined (IBD-U). Mean annual IBD incidence per 100 000 was 1.50 (95% CI: 1.43-1.57). India (9.31; 95% CI: 8.38-10.31) and China (3.64; 95% CI, 2.97-4.42) had the highest IBD incidence in Asia. Incidence of overall IBD (incidence rate ratio [IRR]: 2.19; 95% CI: 1.01-4.76]) and CD (IRR: 3.28; 95% CI: 1.83-9.12) was higher across 19 areas of Asia with a higher population density. In China, incidence of IBD (IRR: 2.37; 95% CI: 1.10-5.16) and UC (IRR: 2.63; 95% CI: 1.2-5.8) was positively associated with gross domestic product. A south-to-north disease gradient (IRR: 0.94; 95% CI: 0.91-0.98) was observed for IBD incidence and a west-to-east gradient (IRR: 1.14; 95% CI: 1.05-1.24) was observed for CD incidence in China. This study received IRB approval. CONCLUSIONS: Regions in Asia with a high population density had a higher CD and UC incidence. Coastal areas within China had higher IBD incidence. With increasing urbanization and a shift from rural areas to cities, disease incidence may continue to climb in Asia.

Early Course of Inflammatory Bowel Disease in a Population-Based Inception Cohort Study From 8 Countries in Asia and Australia.

BACKGROUND & AIMS: The incidence of inflammatory bowel disease (IBD) is increasing in Asia, but little is known about disease progression in this region. The Asia-Pacific Crohn's and Colitis Epidemiology Study was initiated in 2011, enrolling subjects from 8 countries in Asia (China, Hong Kong, Indonesia, Sri Lanka, Macau, Malaysia, Singapore, and Thailand) and Australia. We present data from this ongoing study. METHODS: We collected data on 413 patients diagnosed with IBD (222 with ulcerative colitis [UC], 181 with Crohn's disease [CD], 10 with IBD unclassified; median age, 37 y) from 2011 through 2013. We analyzed the disease course and severity and mortality. Risks for medical and surgical therapies were assessed using Kaplan-Meier analysis. RESULTS: The cumulative probability that CD would change from inflammatory to stricturing or penetrating disease was 19.6%. The cumulative probabilities for use of immunosuppressants or anti-tumor necrosis factor agents were 58.9% and 12.0% for patients with CD, and 12.7% and 0.9% for patients with UC, respectively. Perianal CD was associated with an increased risk of anti-tumor necrosis factor therapy within 1 year of its diagnosis (hazard ratio, 2.97; 95% confidence interval, 1.09-8.09). The cumulative probabilities for surgery 1 year after diagnosis were 9.1% for patients with CD and 0.9% for patients with UC. Patients with CD and penetrating disease had a 7-fold increase for risk of surgery, compared with patients with inflammatory disease (hazard ratio, 7.67; 95% confidence interval, 3.93-14.96). The overall mortality for patients with IBD was 0.7%. CONCLUSIONS: In a prospective population-based study, we found that the early course of disease in patients with IBD in Asia was comparable with that of the West. Patients with CD frequently progress to complicated disease and have accelerated use of immunosuppressants. Few patients with early stage UC undergo surgery in Asia. Increasing our understanding of IBD progression in different populations can help optimize therapy and improve outcomes.

Prevalence and association of pks+ Escherichia coli with colorectal cancer in patients at the University Malaya Medical Centre, Malaysia.

Escherichia coli (E. coli) from the B2 phylogenetic group is implicated in colorectal cancer (CRC) as it possesses a genomic island, termed polyketide synthetase (pks), which codes for the synthesis of colibactin, a genotoxin that induces DNA damage, cell cycle arrest, mutations and chromosomal instability in eukaryotic cells. The aim of this study was to detect and compare the prevalence of E. coli expressing pks (pks+ E. coli) in CRC patients and healthy controls followed by investigating the virulence triggered by pks+ E. coli using an in-vitro model. Mucosal colon tissues were collected and processed to determine the presence of pks+ E. coli. Thereafter, primary colon epithelial (PCE) and colorectal carcinoma (HCT116) cell lines were used to detect cytopathic response to the isolated pks+ E. coli strains. Our results showed 16.7% and 4.3% of CRC and healthy controls, respectively were pks+ E. coli. Further, PCE displayed syncytia and cell swelling and HCT116 cells, megalocytosis, in response to treatment with the isolated pks+ E. coli strains. In conclusion, pks+ E. coli was more often isolated from tissue of CRC patients compared to healthy individuals, and our in-vitro assays suggest these isolated strains may be involved in the initiation and development of CRC.