PUBLICATIONS

2021

Chiang AL, Rabinowitz LG, Alakbarli J, Chan WW. The Patterns and Impact of Social Media Exposure of Journal Publications in Gastroenterology: Retrospective Cohort Study. Journal of medical Internet research. 2021;23(5):e25252. doi:10.2196/25252

BACKGROUND: Medical journals increasingly promote published content through social media platforms such as Twitter. However, gastroenterology journals still rank below average in social media engagement.

OBJECTIVE: We aimed to determine the engagement patterns of publications in gastroenterology journals on Twitter and evaluate the impact of tweets on citations.

METHODS: This was a retrospective cohort study comparing the 3-year citations of all full-length articles published in five major gastroenterology journals from January 1, 2012, to December 31, 2012, tweeted by official journal accounts with those that were not. Multivariate analysis using linear regression was performed to control for journal impact factor, time since publication, article type, frequency of reposting by other users ("retweets"), and media addition to tweets. Secondary analyses were performed to assess the associations between article type or subtopic and the likelihood of social media promotion/engagement.

RESULTS: A total of 1666 articles were reviewed, with 477 tweeted by the official journal account. Tweeting an article independently predicted increased citations after controlling for potential confounders (β coefficient=13.09; P=.007). There was significant association between article type and number of retweets on analysis of variance (ANOVA) (P<.001), with guidelines/technical reviews (mean difference 1.04, 95% CI 0.22-1.87; P<.001) and meta-analyses/systemic reviews (mean difference 1.03, 95% CI 0.35-1.70; P<.001) being retweeted more than basic science articles. The manuscript subtopics most frequently promoted included motility/functional bowel disease (odds ratio [OR] 3.84, 95% CI 1.93-7.64; P<.001) and education (OR 4.69, 95% CI 1.62-13.58; P=.004), while basic science papers were less likely tweeted (OR 0.154, 95% CI 0.07-0.34; P<.001).

CONCLUSIONS: Tweeting of gastroenterology journal articles independently predicted higher 3-year citations. Wider adoption of social media to increase reach and measure uptake of published research should be considered.

2020

Rabiee A, Sadowski B, Adeniji N, et al. Liver Injury in Liver Transplant Recipients With Coronavirus Disease 2019 (COVID-19): U.S. Multicenter Experience. Hepatology (Baltimore, Md.). 2020;72(6):1900-1911. doi:10.1002/hep.31574

BACKGROUND AND AIMS: Coronavirus disease 2019 (COVID-19) is associated with liver injury, but the prevalence and patterns of liver injury in liver transplantation (LT) recipients with COVID-19 are open for study.

APPROACH AND RESULTS: We conducted a multicenter study in the United States of 112 adult LT recipients with COVID-19. Median age was 61 years (interquartile range, 20), 54.5% (n = 61) were male, and 39.3% (n = 44) Hispanic. Mortality rate was 22.3% (n = 25); 72.3% (n = 81) were hospitalized and 26.8% (n = 30) admitted to the intensive care unit (ICU). Analysis of peak values of alanine aminotransferase (ALT) during COVID-19 showed moderate liver injury (ALT 2-5× upper limit of normal [ULN]) in 22.2% (n = 18) and severe liver injury (ALT > 5× ULN) in 12.3% (n = 10). Compared to age- and sex-matched nontransplant patients with chronic liver disease and COVID-19 (n = 375), incidence of acute liver injury was lower in LT recipients (47.5% vs. 34.6%; P = 0.037). Variables associated with liver injury in LT recipients were younger age (P = 0.009; odds ratio [OR], 2.06; 95% confidence interval [CI], 1.20-3.54), Hispanic ethnicity (P = 0.011; OR, 6.01; 95% CI, 1.51-23.9), metabolic syndrome (P = 0.016; OR, 5.87; 95% CI, 1.38-24.99), vasopressor use (P = 0.018; OR, 7.34; 95% CI, 1.39-38.52), and antibiotic use (P = 0.046; OR, 6.93; 95% CI, 1.04-46.26). Reduction in immunosuppression (49.4%) was not associated with liver injury (P = 0.156) or mortality (P = 0.084). Liver injury during COVID-19 was significantly associated with mortality (P = 0.007; OR, 6.91; 95% CI, 1.68-28.48) and ICU admission (P = 0.007; OR, 7.93; 95% CI, 1.75-35.69) in LT recipients.

CONCLUSIONS: Liver injury is associated with higher mortality and ICU admission in LT recipients with COVID-19. Hence, monitoring liver enzymes closely can help in early identification of patients at risk for adverse outcomes. Reduction of immunosuppression during COVID-19 did not increase risk for mortality or graft failure.

Li M, Chan WW, Zucker SD. Association Between Atazanavir-Induced Hyperbilirubinemia and Cardiovascular Disease in Patients Infected with HIV. Journal of the American Heart Association. 2020;9(19):e016310. doi:10.1161/JAHA.120.016310

BACKGROUND: Serum bilirubin is inversely associated with cardiovascular risk. Atazanavir, an HIV protease inhibitor that competitively inhibits bilirubin conjugation, provides a unique opportunity to examine whether selectively increasing bilirubin is cardioprotective. We sought to determine whether patients receiving atazanavir manifest a reduced risk of cardiovascular disease compared with those receiving darunavir, an HIV protease inhibitor that does not increase serum bilirubin.

METHODS AND RESULTS: This was a retrospective cohort study of 1020 patients with HIV. The main outcome was time to myocardial infarction or ischemic stroke. Mean follow-up was 6.6±3.4 years, with 516 receiving atazanavir and 504 darunavir. Atazanavir patients exhibited significantly higher serum total bilirubin (1.7 versus 0.4 mg/dL; P<0.001) and longer mean time to ischemic event (10.2 versus 9.4 years; P<0.001). On Cox regression, atazanavir treatment (hazard ratio [HR], 0.38; 95% CI, 0.21-0.71; P=0.002) and serum bilirubin (HR, 0.60; 95% CI, 0.41-0.89; P=0.011) were independently associated with a lower risk of an ischemic event. Notably, when atazanavir and bilirubin were included together in the Cox regression model, atazanavir lost significance (HR, 0.55; 95% CI, 0.24-1.29; P=0.169) consistent with bilirubin being an intermediate variable on the causal pathway between atazanavir and its effect on cardiovascular disease. Patients on atazanavir also had a significantly lower risk of developing new cardiovascular disease (HR, 0.53; 95% CI, 0.33-0.86; P=0.010) and longer mean time to death (12.2 versus 10.8 years; P<0.001).

CONCLUSIONS: Patients with HIV on atazanavir manifest a decreased risk of cardiovascular disease when compared with those on darunavir, an effect that appears to be mediated by serum bilirubin.

Clarke JO, Ahuja NK, Chan WW, et al. Mucosal impedance for esophageal disease: evaluating the evidence. Annals of the New York Academy of Sciences. 2020;1481(1):247-257. doi:10.1111/nyas.14414

Impedance has traditionally been employed in esophageal disease as a means to assess bolus flow and reflux episodes. Recent and ongoing research has provided new and novel applications for this technology. Measurement of esophageal mucosal impedance, via either multichannel intraluminal impedance catheters or specially designed endoscopically deployed impedance catheters, provides a marker of mucosal integrity. Mucosal impedance has been shown to segregate gastroesophageal reflux disease (GERD) and eosinophilic esophagitis from non-GERD controls and may play a role in predicting response to reflux intervention. More data are needed with regard to other esophageal subgroups, outcome studies, and functional disease. Our paper reviews the history of impedance in esophageal disease, the means of assessing baseline and mucosal impedance, data with regard to the newly developed mucosal impedance probes, the clinical utility of mucosal impedance in specific clinical conditions, and limitations in our existing knowledge, along with suggestions for future studies.

Chan WW, Ahuja N, Fisichella M, Gavini S, Rangan V, Vela MF. Extraesophageal syndrome of gastroesophageal reflux: relationships with lung disease and transplantation outcome. Annals of the New York Academy of Sciences. 2020;1482(1):95-105. doi:10.1111/nyas.14460

Gastroesophageal reflux disease (GERD) is prevalent and may be associated with both esophageal and extraesophageal syndromes, which include various pulmonary conditions. GERD may lead to pulmonary complications through the "reflux" (aspiration) or "reflex" (refluxate-triggered, vagally mediated airway spasm) mechanisms. While GERD may cause or worsen pulmonary disorders, changes in respiratory mechanics due to lung disease may also increase reflux. Typical esophageal symptoms are frequently absent and objective assessment with reflux monitoring is often needed for diagnosis. Impedance monitoring should be considered in addition to traditional pH study due to the involvement of both acidic and weakly acidic/nonacidic reflux. Antireflux therapy may improve outcomes of some pulmonary complications of GERD, although careful selection of a candidate is paramount to successful outcomes. Further research is needed to identify the optimal testing strategy and patient phenotypes that would benefit from antireflux therapy to improve pulmonary outcomes.

Lazarescu A, Chan WW, Gyawali P, Lee YY, Xiao Y, Wu P. Updates on diagnostic modalities for esophageal dysphagia. Annals of the New York Academy of Sciences. 2020;1481(1):108-116. doi:10.1111/nyas.14453

Esophageal dysphagia is a common symptom in adults. Fluoroscopic contrast studies, endoscopy, and esophageal manometry have been used in the diagnosis of esophageal dysphagia for many years. The diagnostic yield has been improved with new test protocols that highlight abnormal bolus transit in the esophagus and outflow obstruction, as well as new high-definition and high-resolution technical advances in equipment. Functional luminal impedance planimetry and the addition of impedance to high-resolution esophageal manometry have also allowed the assessment of new parameters to better understand esophageal structure and function. In this concise review, we describe the role and utility of various diagnostic modalities in the assessment of patients with esophageal dysphagia.

Lo WK, Moniodis A, Goldberg HJ, Feldman N, Chan WW. Increased Acid Exposure on Pretransplant Impedance-pH Testing Is Associated With Chronic Rejection After Lung Transplantation. Journal of clinical gastroenterology. 2020;54(6):517-521. doi:10.1097/MCG.0000000000001331

GOAL: The goal of this study was to assess the relationship between pretransplant measures of reflux and longer-term outcomes of chronic allograft rejection in lung transplant recipients.

BACKGROUND: Bronchiolitis obliterans syndrome (BOS) is a primary measure of morbidity and mortality following lung transplantation, and a manifestation of chronic lung allograft dysfunction (CLAD). Acid reflux has been associated with early allograft injury through a proposed mechanism of aspiration and activation of the inflammatory cascade, but its association with chronic rejection is unclear.

STUDY: This was a retrospective cohort study of lung transplant recipients undergoing impedance-pH testing off proton pump inhibitor from 2007 to 2016. Patients with pretransplant antireflux surgery were excluded. Time-to-event analysis using the Cox proportional hazards model was applied to assess the relationship between pretransplant reflux measures and the development of BOS, defined histologically and clinically. A secondary analysis was completed using CLAD as the outcome variable.

RESULTS: Fifty-one subjects (59% men, mean age: 56, mean follow-up: 2.2 y) met inclusion criteria for the study. The BOS endpoint was reached in 13 subjects (28%). In time-to-event analyses, BOS was associated with increased acid exposure, defined as >4.2% of time with pH<4 [hazard ratio (HR): 4.18; 95% confidence interval (CI): 1.31-13.4; P=0.01], and elevated DeMeester score >14.7 (HR: 3.08; 95% CI: 1.02-9.26; P=0.04), with confirmation from Kaplan-Meier analyses. The secondary analysis demonstrated a similar association between increased acid exposure and CLAD (HR: 3.28; 95% CI: 1.09-9.88; P=0.03), which persisted on multivariate models.

CONCLUSION: Increased acid exposure on pretransplant reflux testing was associated with the development of BOS and CLAD, both measures of chronic allograft rejection, after lung transplantation, and may provide clinically relevant information to improve lung allograft survival through aggressive reflux management.

Hathorn KE, Chan WW, Aihara H, Thompson CC. Determining the Safety and Effectiveness of Electrocautery Enhanced Scissors for Peroral Endoscopic Myotomy (with Video). Clinical endoscopy. 2020;53(4):443-451. doi:10.5946/ce.2019.214

BACKGROUND/AIMS: Peroral endoscopic myotomy (POEM) has recently come to the forefront in the management of achalasia. We aimed to analyze the efficacy and safety of the use of electrocautery enhanced scissors (EES) for POEM.

METHODS: This retrospective cohort study prospectively collected the data of all adult patients (aged ≥18 years) with normal foregut anatomy who underwent POEM using EES. The patients' baseline characteristics and procedure details (time, tunnel length, myotomy length, depth, and location) were recorded. The primary outcome was clinical success (3-month post-procedure Eckardt score of ≤3). The secondary outcomes were technical success and adverse events. A paired Student's t-test was performed.

RESULTS: Fifteen patients were included in this study. The technical success rate of myotomy using EES was 100%. Fellows participated in the myotomy in all cases. The clinical success rate was 93.3% (14/15). The mean pre-Eckardt score was 5.4±2.5, while the mean post-Eckardt score was 1.3±1.3, which indicated a significant improvement (p≤0.0001). The most common treatment-related adverse events were post-procedure pain (4, 26.7%) and symptomatic reflux disease (4, 26.7%).

CONCLUSION: In the largest series to date on the use of EES in POEM, we demonstrated that this technique has both technical and clinical efficacy as well as an excellent safety profile.

McNabb-Baltar J, Jin DX, Grover AS, et al. Lipase Elevation in Patients With COVID-19. The American journal of gastroenterology. 2020;115(8):1286-1288. doi:10.14309/ajg.0000000000000732

INTRODUCTION: Although coronavirus disease (COVID-19) has been associated with gastrointestinal manifestations, its effect on the pancreas remains unclear. We aimed to assess the frequency and characteristics of hyperlipasemia in patients with COVID-19.

METHODS: A retrospective cohort study of hospitalized patients across 6 US centers with COVID-19.

RESULTS: Of 71 patients, 9 (12.1%) developed hyperlipasemia, with 2 (2.8%) greater than 3 times upper limit of normal. No patient developed acute pancreatitis. Hyperlipasemia was not associated with poor outcomes or symptoms.

DISCUSSION: Although a mild elevation in serum lipase was observed in some patients with COVID-19, clinical acute pancreatitis was not seen.