Comparing artificial intelligence to humans for endoscopic diagnosis of gastric neoplasia: An external validation study.

OBJECTIVES: Artificial intelligence (AI) uses deep learning functionalities that may enhance the detection of early gastric cancer during endoscopy. An AI-based endoscopic system for upper endoscopy was recently developed in Japan. We aim to validate this AI-based system in a Singaporean cohort. METHODS: There were 300 de-identified still images prepared from endoscopy video files obtained from subjects that underwent gastroscopy in National University Hospital (NUH). Five specialists and 6 non-specialists (trainees) from NUH were assigned to read and categorize the images into "neoplastic" or "non-neoplastic." Results were then compared with the readings performed by the endoscopic AI system. RESULTS: The mean accuracy, sensitivity, and specificity for the 11 endoscopists were 0.847, 0.525, and 0.872, respectively. These values for the AI-based system were 0.777, 0.591, and 0.791, respectively. While AI in general did not perform better than endoscopists on the whole, in the subgroup of high-grade dysplastic lesions, only 29.1% were picked up by the endoscopist rating, but 80% were classified as neoplastic by AI (P = 0.0011). The average diagnostic time was also faster in AI compared with endoscopists (677.1 s vs 42.02 s (P < 0.001). CONCLUSION: We demonstrated that an AI system developed in another health system was comparable in diagnostic accuracy in the evaluation of static images. AI systems are faster and not fatigable and may have a role in augmenting human diagnosis during endoscopy. With more advances in AI and larger studies to support its efficacy it would likely play a larger role in screening endoscopy in future.

Academy of Medicine, Singapore clinical guideline on endoscopic surveillance and management of gastric premalignant lesions.

Gastric cancer (GC) has a good prognosis, if detected at an early stage. The intestinal subtype of GC follows a stepwise progression to carcinoma, which is treatable with early detection and intervention using high-quality endoscopy. Premalignant lesions and gastric epithelial polyps are commonly encountered in clinical practice. Surveillance of patients with premalignant gastric lesions may aid in early diagnosis of GC, and thus improve chances of survival. An expert professional workgroup was formed to summarise the current evidence and provide recommendations on the management of patients with gastric premalignant lesions in Singapore. Twenty-five recommendations were made to address screening and surveillance, strategies for detection and management of gastric premalignant lesions, management of gastric epithelial polyps, and pathological reporting of gastric premalignant lesions.

Severity of gastric intestinal metaplasia predicts the risk of gastric cancer: a prospective multicentre cohort study (GCEP).

OBJECTIVE: To investigate the incidence of gastric cancer (GC) attributed to gastric intestinal metaplasia (IM), and validate the Operative Link on Gastric Intestinal Metaplasia (OLGIM) for targeted endoscopic surveillance in regions with low-intermediate incidence of GC. METHODS: A prospective, longitudinal and multicentre study was carried out in Singapore. The study participants comprised 2980 patients undergoing screening gastroscopy with standardised gastric mucosal sampling, from January 2004 and December 2010, with scheduled surveillance endoscopies at year 3 and 5. Participants were also matched against the National Registry of Diseases Office for missed diagnoses of early gastric neoplasia (EGN). RESULTS: There were 21 participants diagnosed with EGN. IM was a significant risk factor for EGN (adjusted-HR 5.36; 95% CI 1.51 to 19.0; p<0.01). The age-adjusted EGN incidence rates for patients with and without IM were 133.9 and 12.5 per 100 000 person-years. Participants with OLGIM stages III-IV were at greatest risk (adjusted-HR 20.7; 95% CI 5.04 to 85.6; p<0.01). More than half of the EGNs (n=4/7) attributed to baseline OLGIM III-IV developed within 2 years (range: 12.7-44.8 months). Serum trefoil factor 3 distinguishes (Area Under the Receiver Operating Characteristics 0.749) patients with OLGIM III-IV if they are negative for H. pylori. Participants with OLGIM II were also at significant risk of EGN (adjusted-HR 7.34; 95% CI 1.60 to 33.7; p=0.02). A significant smoking history further increases the risk of EGN among patients with OLGIM stages II-IV. CONCLUSIONS: We suggest a risk-stratified approach and recommend that high-risk patients (OLGIM III-IV) have endoscopic surveillance in 2 years, intermediate-risk patients (OLGIM II) in 5 years.

The effectiveness of the Safety in Interventional Radiology (SIR) Shield in reducing droplet transmission and its effect on image quality and radiation dose.

OBJECTIVE: To evaluate the efficacy of a barrier shield in reducing droplet transmission and its effect on image quality and radiation dose in an interventional suite. METHODS: A human cough droplet visualisation model in a supine position was developed to assess efficacy of barrier shield in reducing environmental contamination. Its effect on image quality (resolution and contrast) was evaluated via image quality test phantom. Changes in the radiation dose to patient post-shield utilisation was measured. RESULTS: Use of the shield prevented escape of visible fluorescent cough droplets from the containment area. No subjective change in line-pair resolution was observed. No significant difference in contrast-to-noise ratio was measured. Radiation dosage to patient was increased; this is predominantly attributed to the increased air gap and not the physical properties of the shield. CONCLUSION: Use of the barrier shield provided an effective added layer of personal protection in the interventional radiology theatre for aerosol generating procedures. ADVANCES IN KNOWLEDGE: This is the first time a human supine cough droplet visualisation has been developed. While multiple types of barrier shields have been described, this is the first systematic practical evaluation of a barrier shield designed for use in the interventional radiology theatre.

Non-obese non-alcoholic fatty liver disease (NAFLD) in Asia: an international registry study.

BACKGROUND: A significant proportion of the non-alcoholic fatty liver disease (NAFLD) population is non-obese. Prior studies reporting the severity of NAFLD amongst non-obese patients were heterogenous. Our study, using data from the largest biopsy-proven NAFLD international registry within Asia, aims to characterize the demographic, metabolic and histological differences between non-obese and obese NAFLD patients. METHODS: 1812 biopsy-proven NAFLD patients across nine countries in Asia assessed between 2006 and 2019 were pooled into a curated clinical registry. Demographic, metabolic and histological differences between non-obese and obese NAFLD patients were evaluated. The performance of Fibrosis-4 index for liver fibrosis (FIB-4) and NAFLD fibrosis score (NFS) to identify advanced liver disease across the varying obesity subgroups was compared. A random forest analysis was performed to identify novel predictors of fibrosis and steatohepatitis in non-obese patients. FINDINGS: One-fifth (21.6%) of NAFLD patients were non-obese. Non-obese NAFLD patients had lower proportions of NASH (50.5% vs 56.5%, p = 0.033) and advanced fibrosis (14.0% vs 18.7%, p = 0.033). Metabolic syndrome in non-obese individuals was associated with NASH (OR 1.59, 95% CI 1.01-2.54, p = 0.047) and advanced fibrosis (OR 1.88, 95% CI 0.99-3.54, p = 0.051). FIB-4 performed better than the NFS score (AUROC 81.5% vs 73.7%, p < 0.001) when classifying patients with F2-4 fibrosis amongst non-obese NAFLD patients. Haemoglobin, GGT, waist circumference and cholesterol are additional variables found on random forest analysis useful for identifying non-obese NAFLD patients with advanced liver disease. CONCLUSION: A substantial proportion of non-obese NAFLD patients has NASH or advanced fibrosis. FIB-4, compared to NFS better identifies non-obese NAFLD patients with advanced liver disease. Serum GGT, cholesterol, haemoglobin and waist circumference, which are neither components of NFS nor FIB-4, are important biomarkers for advanced liver disease in non-obese patients.

Are migrant workers in Singapore receiving adequate healthcare? A survey of doctors working in public tertiary healthcare institutions.

INTRODUCTION: Migrant workers comprise about one-fifth of Singapore's resident population and form a substantial and vital component of the nation's workforce. However, limited data is available regarding the barriers that migrant workers face in accessing healthcare from the healthcare providers' perspective. METHODS: We conducted a survey on doctors working in four restructured hospitals in Singapore, to assess what they perceived to be barriers faced by migrant workers in accessing healthcare. We also assessed the doctors' understanding of migrant-health-related policies in Singapore. RESULTS: A total of 427 survey responses were collected. Most respondents were senior doctors (senior residents or consultants) who had been practising medicine for a median of ten years. Among doctors, the most common perceived barriers to migrant workers accessing healthcare were related to culture/language (92.3%) and finances (healthcare cost) (81.0%). Of the six questions asked pertaining to migrant healthcare policy in Singapore, the respondents achieved a median of four correctly answered questions (interquartile range 3-5), and about 55% were unaware or unsure of available resources for migrant workers. CONCLUSION: Our study identified healthcare providers' perceived barriers to the delivery of healthcare to migrant workers, which corroborate previously published data reported by migrant workers themselves. Further efforts should be directed towards diminishing these barriers and increasing the literacy of migrant health among healthcare workers.

Probiotics in health and disease: fooling Mother Nature?

Probiotics are ubiquitous, consumption by the general public is common, and the dogma remains that they are beneficial for general and gut health. However, evolving evidence suggests a potentially "harmful" impact of many commercially available probiotics. There is also significant variability in formulations that leads to a lack of a universally acceptable definition of probiotics. In this perspective, we review the flaws with definition, relevant observational and randomized studies that showed both positive and negative impacts on health and disease, unbiased interpretation of key trials, emerging evidence from microbiome and immuno-oncological studies, and impact on systemic immunity. We propose that caution be exercised prior to endorsements of their illness-directed consumption and rampant general usage. As a deeper understanding of the human microbiome accrues and our ability to manipulate this complex ecosystem improves, the probiotic of tomorrow might be the precision tool that deals with diseases on a broad front. Gut microbiome, akin to fingerprints, is indigenous to an individual and 'one size fits all' prescription strategy should be discouraged until a more universally acceptable 'favorable taxa' or a 'personalized probiotic,' to complement an individual's native microbiota, gets fashioned.

Healthcare-seeking behaviour, barriers and mental health of non-domestic migrant workers in Singapore.

BACKGROUND: Low-wage migrant workers are vulnerable to healthcare inequities. We sought to identify potential barriers to healthcare and risk factors for mental health issues in non-domestic migrant workers in Singapore, and identify high-risk subgroups. METHODS: A cross-sectional, interviewer-administered survey of 433 non-domestic migrant workers was conducted at subsidised clinics and a foreign worker dormitory from July to August 2016. Questions assessed healthcare usage patterns, affordability issues, barriers to care and psychological distress using a validated screening scale (Kessler-6). FINDINGS: Bangladeshi workers surveyed were more likely to be single, have more financial dependents, a lower level of education and salary and pay higher agent fees (p<0.01). 61.4% of workers reported that they had insurance, but had poor understanding of whether it covered inpatient/outpatient expenses. The majority of workers had not, or were not sure if they had, received information about company-bought insurance (72.4%). Among those who had, most reported that information was not in their native language (67.7%). Non-specific psychological distress was found in 21.9%, as estimated by the Kessler-6 scale. Multivariate analysis found that psychological distress was independently associated with Bangladeshi nationals (OR 2.98, 95% CI 1.58 to 5.62; p=0.001) and previous experience of financial barriers to healthcare (OR 3.86, 95% CI 2.25 to 6.62; p<0.0001). INTERPRETATION: We identified gaps in non-domestic migrant workers' knowledge of healthcare coverage, and substantial financial barriers to healthcare. The Bangladeshi population in our study was at higher risk of such barriers and psychological distress. These represent areas for further research and intervention.

Cost-effectiveness of strategy-based approach to treatment of genotype 1 chronic hepatitis C.

BACKGROUND AND AIM: The high cost of chronic hepatitis C (HCV) direct-acting antivirals (DAAs) poses significant financial challenges for health payers, especially in Asia. A personalized treatment strategy based on individualized probability of virological response using oral DAAs as second-line therapy would seem practical but has not been studied. METHODS: We performed a Markov model to project health outcomes and costs for patients with genotype 1 HCV through 10 treatment strategies over a lifetime period. The implication of retreatment was also incorporated to reflect real-life situation. RESULTS: Using boceprevir and peginterferon/ribavirin (BOC/PR, the least costly treatment) as a base case, the all-oral therapies such as ombitasvir/paritaprevir/ritonavir-dasabuvir are cost-effective with an incremental cost-effective ratio of $US50 828. However, the all-oral DAAs would no longer be cost-effective compared with conventional therapies if retreatment were taken into account. A road map strategy using rapid virological response to guide use of BOC/PR and sofosbuvir/PR had the most favorable incremental cost-effective ratio ($US27 782) relative to BOC/PR. Nevertheless, the trade-off with the cost-effectiveness of the road map strategy is an increased number of liver-related deaths compared with all-oral DAAs (52 vs 10-20 per 10 000 patients) by incorporating retreatment. CONCLUSIONS: The 12-week all-oral DAAs were cost-effective options using conventional drug-to-drug comparison. However, they cease to be cost-effective when treatment strategies incorporating DAA retreatment for interferon failures are incorporated. HCV management can be optimized by adopting individualized treatment algorithm providing a practical solution to health payers to make oral DAAs accessible to those who need them most.