The use of mechanistic reasoning in assessing coronavirus interventions

Funder: Marie Curie; Id: http://dx.doi.org/10.13039/501100000654Funder: Wellcome; Id: http://dx.doi.org/10.13039/100010269Funder: MRC: Medical Research CouncilFunder: NIHR: National Institute For Health ResearchAbstract: Rationale: Evidence‐based medicine (EBM), the dominant approach to assessing the effectiveness of clinical and public health interventions, focuses on the results of association studies. EBM+ is a development of EBM that systematically considers mechanistic studies alongside association studies. Aims and objectives: To explore examples of the importance of mechanistic evidence to coronavirus research. Methods: We have reviewed the mechanistic evidence in four major areas that are relevant to the management of COVID‐19. Results and conclusions: (a) Assessment of combination therapy for MERS highlights the need for systematic assessment of mechanistic evidence. (b) That hypertension is a risk factor for severe disease in the case of SARS‐CoV‐2 suggests that altering hypertension treatment might alleviate disease, but the mechanisms are complex, and it is essential to consider and evaluate multiple mechanistic hypotheses. (c) Confidence that public health interventions will be effective requires a detailed assessment of social and psychological components of the mechanisms of their action, in addition to mechanisms of disease. (d) In particular, if vaccination programmes are to be effective, they must be carefully tailored to the social context; again, mechanistic evidence is crucial. We conclude that coronavirus research is best situated within the EBM+ evaluation framework

Incidence trends of colorectal cancer in the early 2000s in Italy. Figures from the IMPATTO study on colorectal cancer screening

We utilised the IMPATTO study's archives to describe the 2000-2008 colorectal cancer (CRC) incidence rate trends in Italy, once screening programmes based on the faecal immunochemical test were implemented in different areas. Data on CRCs diagnosed in Italy from 2000 to 2008 in subjects aged 40-79 years were collected by 23 cancer registries. Incidence rate trends were evaluated as a whole and by macro-area (North-Centre and South-Islands), presence of a screening programme, sex, ten-year age class, anatomic site, stage at diagnosis, and pattern of diagnosis (screen-detected, non-screen-detected). The annual percent change (APC) of incidence rate trends, with 95% confidence intervals (95%CI), were computed. The study included 46,857 CRCs diagnosed in subjects aged 40-79 years, of which 2,806 were screendetected. The incidence rates in the North-Centre were higher than in the South and on the Islands. During the study period, screening programmes had been implemented only in the North-Centre and had a significant effect on incidence rates, with an initial sharp increase in incidence, followed by a decrease that started in the 3rd-4th years of screening. These incidence rate trends were exclusively due to modifications in the rates of stage I cases. After screening programmes started, incidence increased in all anatomic sites, particularly in the distal colon. The differential figures introduced by the implementation of screening programmes warrant a continuous surveillance of CRC incidence and mortality trends to monitor the impact of screening at a national level

Characteristics of the colorectal cancers diagnosed in the early 2000s in Italy. Figures from the IMPATTO study on colorectal cancer screening

The impact of organized screening programmes on colorectal cancer (CRC) can be observed at a population level only several years after the implementation of screening. We compared CRC characteristics by diagnostic modality (screen-detected, non-screen-detected) as an early outcome to monitor screening programme effectiveness. Data on CRCs diagnosed in Italy from 2000 to 2008 were collected by several cancer registries. Linkage with screening datasets made it possible to divide the cases by geographic area, implementation of screening, and modality of diagnosis (screen-detected, non-screen-detected).We compared the main characteristics of the different subgroups of CRCs through multivariate logistic regression models. The study included 23,668 CRCs diagnosed in subjects aged 50-69 years, of which 11.9%were screendetected (N=2,806), all from the North-Centre of Italy. Among screen-detected CRCs, we observed a higher proportion of males, of cases in the distal colon, and a higher mean age of the patients. Compared with pre-screening cases, screen-detected CRCs showed a better distribution by stage at diagnosis (OR for stage III or IV: 0.40, 95%CI: 0.36-0.44) and grading (OR for poorly differentiated CRCs was 0.86, 95%CI: 0.75-1.00). Screen-detected CRCs have more favourable prognostic characteristics than non-screen-detected cases. A renewed effort to implement screening programmes throughout the entire country is recommended

Pre-Endoscopy real-time PCR testing for SARS-CoV2 does not reduce health care workers infection and is associated with a higher reduction of endoscopic activity in an outpatient setting

Objective: The role of pre-procedure SARS-CoV2 testing in digestive endoscopy is still debated. AGA guidelines recommend against pre-procedure testing considering low prevalence of SARS-CoV2 infection in the general population and low incidence of infection among endoscopy units Health Care Workers (HCWs). However, no studies have compared pre-procedure testing associated to symptom screening vs. symptom screening alone in reducing the risk of infection for HCWs. Main aim of the present study is to compare the risk of infection for HCWs in different Endoscopy Units adopting different pre-endoscopy screening and operating in two nearby hospital of the same region in Northern Italy in pre-vaccination period. For outpatients in the Endoscopy Unit of Trento (Unit 1) only pre-procedure symptom screening was performed, while in the Endoscopy Unit of Bolzano (Unit 2) pre-procedure symptom screening and negative pre-procedure real-time PCR were requested. Secondary aims were to assess the impact of pre-procedure real-time PCR testing on endoscopic activity and diagnostic delay.Design: Retrospective data collection on a prospectively maintained database was performed, including outpatient endoscopy procedures performed between June 1st 2020 and February 28th 2021 in Unit 1 and Unit 2.Results: No differences in terms of infection rate in HCWs have been identified in Unit 1 and Unit 2 (9.0 vs. 19.3% P=0.2) over a nine-month period. Moreover, in the unit performing pre-procedure real-time PCR before endoscopy a significantly higher reduction in endoscopic activity has been recorded (61.9% vs. 53.4%; P<0.01). In patients with positive real-time PCR, endoscopy was performed with a mean delay of 61.7 days (range 9-294) and 22.5% of them were lost at follow-up and did not undergo any endoscopic procedure in the following 12 months.Conclusions: This study supports the AGA recommendation suggesting that pre-endoscopy real-time PCR is an expensive and time-consuming procedure without proven benefits in an outpatient setting. (Acta gastroenterol. belg., 2022, 85, 581-585)

Secondary analysis of large databases for hepatology research

Secondary analysis of large datasets involves the utilization of existing data that has typically been collected for other purposes to advance scientific knowledge. This is an established methodology applied in health services research with the unique advantage of efficiently identifying relationships between predictor and outcome variables but which has been underutilized for hepatology research. Our review of 1431 abstracts published in the 2013 European Association for the Study of Liver (EASL) abstract book showed that less than 0.5% of published abstracts utilized secondary analysis of large database methodologies.This review paper describes existing large datasets that can be exploited for secondary analyses in liver disease research. It also suggests potential questions that could be addressed using these data warehouses and highlights the strengths and limitations of each dataset as described by authors that have previously used them. The overall goal is to bring these datasets to the attention of readers and ultimately encourage the consideration of secondary analysis of large database methodologies for the advancement of hepatology. (C) 2015 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved

Pancreatic cysts: Diagnostic accuracy and risk of inappropriate resections

Background: Pancreatic cystic neoplasms (PCN) frequently undergo surgery, given malignant potential. Pancreatic cyst surgery is associated with significant rates of morbidity and mortality. It is crucial to accurately characterize these lesions pre-operatively to avoid unnecessary surgery in patients with benign pancreatic cysts.Aim: We aimed to assess the correlation between pre-operative (pre-op) diagnosis based on imaging and clinical presentation, and post-operative (post-op) diagnosis based on histopathology in patients undergone pancreatic cyst surgery.Methods: From January 2000 to January 2012, we randomly selected 2000 patients with ICD-9 code 211.6 and 577.2. Amongst these we identified 281 patients undergone pancreas surgery. Patients with no pre-op imaging or non-cyst indication for surgery were excluded (n = 107). Imaging details, demographics, pre-operative physician diagnosis and histopathologic details of pancreatic cysts were recorded in 174 patients.Results: There was a discrepancy between the pre- and post-operative pancreatic cyst diagnosis in 54 (31%) patients. There was no difference in the proportion of various imaging studies (CT, EUS or MRI) between patients with a correct and patients with an incorrect pre-op diagnosis. The pre-op diagnosis was confirmed at pathology in 87.5% of the presumed SCNs, in 80% of the presumed pseudocysts, in 73.3% of the presumed BD-IPMNs, in 66.7% of the presumed MD/mixed-IPMNs and in 53.6% of the presumed MCNs. The accuracy of the pre-operative diagnosis of presumed MCN was significantly lower compared to the non-MCN cysts (53.6% vs. 75%; p = 0.037). Fourteen percent of resections were performed for asymptomatic benign cysts, preoperatively suspected to be potentially pre-malignant cysts.Conclusion: In nearly 1 out of 3 patients undergone pancreas cyst surgery, there is a discrepancy between pre- and post-op diagnosis. Pre-op diagnosis of presumed MCN is more likely to be incorrect, compared to the other cysts. (C) 2017 IAP and EPC. Published by Elsevier B.V. All rights reserved