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Biomedical subjects

Nicholas J Shaheen

Publications and source records attributed to Nicholas J Shaheen.

At least 19 recordsLinked to original sources

Value of HCC surveillance in a landscape of emerging surveillance options: Perspectives of a multi-stakeholder modified Delphi panel.

HCC surveillance is recommended by liver professional societies but lacks broad acceptance by several primary care and cancer societies due to limitations in the existing data. We convened a diverse multidisciplinary group of cancer screening experts to evaluate current and future paradigms of HCC prevention and early detection using a rigorous Delphi panel approach. The experts had high agreement on 21 statements about primary prevention, HCC surveillance benefits, HCC surveillance harms, and the evaluation of emerging surveillance modalities. The experts agreed that current data have methodologic limitations as well as unclear generalizability to Western populations. Although a randomized clinical trial of surveillance versus no surveillance is unlikely feasible, they concurred that alternative designs, such as a comparison of 2 surveillance modalities, could provide indirect evidence of surveillance efficacy. The panel acknowledged the presence of surveillance harms, but concurred the overall value of surveillance appears high, particularly given a greater emphasis on benefits over harms by both patients and clinicians. The experts underscored the importance of a framework for measuring both benefits and harms when evaluating emerging surveillance strategies. The panel acknowledged performance metrics of emerging methods may differ from other cancer screening programs given differences in populations, including higher risk of cancer development and competing risk of morality, and differences in diagnostic workflow in patients at risk of HCC. These data provide insights into the perceived value of HCC surveillance in an era of emerging blood- and imaging-based surveillance strategies.

Humans↗

Molecular Analysis of Persistent and Recurrent Barrett's Esophagus in the Setting of Endoscopic Therapy.

INTRODUCTION: Early neoplastic progression of Barrett's esophagus (BE) is often treated with endoscopic therapy. Although effective, some patients are refractory to therapy or recur after apparent eradication of the BE. The goal of this study was to determine whether genomic alterations within the treated BE may be associated with persistent or recurrent disease. METHODS: We performed DNA sequencing on pre-treatment esophageal samples from 45 patients who were successfully treated by endoscopic therapy and did not recur as well as pre-treatment and post-treatment samples from 40 patients who had persistent neoplasia and 21 patients who had recurrent neoplasia. The genomic alterations were compared between groups. RESULTS: The genomic landscape was similar between all groups. Patients with persistent disease were more likely to have pre-treatment alterations involving the receptor tyrosine kinase pathway ( P = 0.01), amplifications of oncogenes ( P = 0.01), and deletions of tumor suppressor genes ( P = 0.02). These associations were no longer significant after adjusting for patient age and BE length. More than half of patients with persistent (52.5%) or recurrent (57.2%) disease showed pre-treatment and post-treatment samples that shared at least 50% of their driver mutations. DISCUSSION: Pre-treatment samples were genomically similar between those who responded to endoscopic therapy and those who had persistent or recurrent disease, suggesting there is not a strong genomic component to treatment response. Although it was expected to find shared driver mutations in pre-treatment and post-treatment samples in patients with persistent disease, the finding that an equal number of patients with recurrent disease also showed this relation suggests that many recurrences represent undetected minimal residual disease.

Humans↗

Association of industry sponsorship to published outcomes in gastrointestinal clinical research.

BACKGROUND & AIMS: Recent years have seen an increase in industry sponsorship of clinical trials throughout medicine. We conducted a study to evaluate the association of industry sponsorship to published outcomes in gastrointestinal (GI) clinical research. Our aims were (1) to evaluate the trends in the source of funding for GI clinical research during the period from 1992 to 2002-2003, (2) to determine whether the source of study funding predicted the likelihood that a study would publish results that favor the drug or device being tested, and (3) to determine whether differences exist in the methodologic quality of the investigational study methods used in studies funded by private industry versus other sources. METHODS: We selected all clinical studies evaluating a drug or device from 4 prominent GI journals (Gastroenterology, The American Journal of Gastroenterology, Hepatology, and Gastrointestinal Endoscopy). All studies were abstracted by using a standardized data abstraction form. We evaluated the trends in funding source for studies published during the years 1992, 2002, and 2003. All selected studies were scored for methodologic quality by using a previously validated scoring system. The percentage of studies that reported outcomes that favored the device or drug being tested against the standard therapy or placebo was determined for each funding source. A funnel plot was constructed to assess for the presence of negative publication bias. RESULTS: A total of 6326 studies were reviewed. For the 1992 trend data, 1860 studies were reviewed, and 135 were selected for inclusion in the study. Ninety-five studies were studies involving the investigation of drugs, and 40 studies involved the testing of a device. For the 2002-2003 data 4466 studies were reviewed, and 315 were selected for inclusion in the study. Two hundred twenty-two studies were clinical trials involving the investigation of drugs, and 93 were clinical trials involving devices. In comparing 1992 to 2002, the percentage of studies funded by industry sources more than doubled from 10% to greater than 28% of the total studies assessed. There was an associated decline in the proportion of studies with funding from non-industry sources during this period (62% to less than 48%). The percentage of studies that did not disclose a funding source fell modestly from 28% to 24%. We found that 86% of studies funded by private industry reported a result favorable to the study drug or device, and 83% of studies funded by academic sources reported a result favorable to the study drug or device (P=.572). On average, studies funded by private industry had a higher methodology score than studies funded by traditional academic sources (75 of 100 vs 65 of 100; P=.005). Analysis of the funnel plot did not reveal evidence of bias against the publication of small studies with insignificant results. CONCLUSIONS: The proportion of research funded by industry has more than doubled during the last decade and currently comprises almost half of the funding for GI clinical research. Industry-sponsored studies are, on average, of superior methodologic quality to studies funded by other sources. Industry-sponsored studies in leading GI journals were no more likely than other studies to publish results that favored the study sponsor, although an extremely high percentage of all studies in these journals reported positive results. There has been only a modest decline in studies not acknowledging a funding source.

Clinical Trials as Topic↗

A very low-carbohydrate diet improves gastroesophageal reflux and its symptoms.

Obese patients with gastroesophageal reflux disease (GERD) may experience resolution of symptoms utilizing a very low-carbohydrate diet. The mechanism of this improvement is unknown. This studied aimed to prospectively assess changes in distal esophageal acid exposure and GERD symptoms among obese adults initiating a very low-carbohydrate diet. We studied obese individuals with GERD initiating a diet containing less than 20 g/day of carbohydrates. Symptom severity was assessed using the GERD Symptom Assessment Scale--Distress Subscale (GSAS-ds). Participants underwent 24-hr esophageal pH probe testing and initiated the diet upon its completion. Within 6 days, a second pH probe test was performed. Outcomes included changes in the Johnson-DeMeester score, percentage total time with a pH<4 in the distal esophagus, and GSAS-ds scores. Eight participants were enrolled. Mean Johnson-DeMeester score decreased from 34.7 to 14.0 (P=0.023). Percentage time with pH<4 decreased from 5.1% to 2.5% (P=0.022). Mean GSAS-ds score decreased from 1.28 to 0.72 (P=0.0004). These data suggest that a very low-carbohydrate diet in obese individuals with GERD significantly reduces distal esophageal acid exposure and improves symptoms.

Adolescent↗

The burden of gastrointestinal and liver diseases, 2006.

BACKGROUND: Digestive and liver diseases are a source of significant morbidity, mortality, and health-care costs for the U.S. population. An annual report of the toll of these diseases could be helpful to clinicians, policymakers, and researchers. AIM: To describe the epidemiology of gastrointestinal and liver diseases in the United States using data from privately and publicly held databases. METHODS: We collected data from the National Center for Health Statistics, the National Ambulatory Medical Care Survey, the National Inpatient Sample, the Centers for Disease Control and Prevention, and the National Cancer Institute, as well as proprietary pharmaceutical databases to construct a report on the impact of gastrointestinal and liver diseases on the U.S. population. We compiled information on causes of death, hospitalization, clinic visits, cancer incidence, and mortality and infectious disease incidence from these databases, and extracted data specific to gastrointestinal diseases. Because of the high costs associated with medications used to treat gastrointestinal diseases, we also include in this year's report a special section on pharmacoepidemiology and pharmacoeconomics. RESULTS: Colorectal cancer continues to be the leading cause of GI-related death, although the data indicate a downward trend in deaths. Abdominal pain, diarrhea, vomiting, and nausea are the most common GI symptoms precipitating a visit to the physician, and GERD is the most common GI-related diagnosis given in office visits. Chest pain not specified to be cardiac in origin is the most common cause of inpatient admission possibly related to GI disease, with cholelithiasis and pancreatitis following. Americans spend in excess of US dollars 10 billion/yr on proton pump inhibitors (PPIs), and two of the top five selling drugs in the United States are PPIs. Trends in PPI use demonstrate turbulent changes, likely reflecting both new drug entries into the field, as well as drug marketing. The number of PPI prescriptions/yr in the United States has doubled since 1999. Twenty-three drugs used for gastrointestinal diseases are among the top 200 generic drugs used in the United States. CONCLUSIONS: Gastrointestinal and liver diseases are significant contributors to the morbidity, mortality, and health-care expenditures of the U.S. population.

Female↗

The impact of the changing health care environment on the health and well-being of faculty at four medical schools.

PURPOSE: Increased pressure for clinical and research productivity and decreased control over the work environment have been reported to have adverse impacts on academic faculty in limited studies. The authors examined whether work-related stressors in academic medicine negatively affected the physical and mental health, as well as life and job satisfaction, of academic medical school faculty. METHOD: A 136-item self-administered anonymous questionnaire modified from a small 1984 study was distributed to 3,519 academic faculty at four U.S. medical schools following institutional review board approval at each school. Validated scales measuring depression, anxiety, work strain, and job and life satisfaction; a checklist of common physical and mental health symptoms; and questions about the impact of institutional financial stability, colleague attrition, and other work-related perceptions were used. Responses were analyzed by sex, academic rank, age, marital status, faculty discipline, and medical school. RESULTS: Responses were received from 1,951 full-time academic physicians and basic science faculty, a 54.3% response rate. Twenty percent of faculty, almost equal by sex, had significant levels of depressive symptoms, with higher levels in younger faculty. Perception of financial instability was associated with greater levels of work strain, depression, and anxiety. Significant numbers of faculty acknowledged that work-related strain negatively affected their mental health and job satisfaction, but not life satisfaction or physical health. Specialties were differentially affected. CONCLUSIONS: High levels of depression, anxiety, and job dissatisfaction-especially in younger faculty-raise concerns about the well-being of academic faculty and its impact on trainees and patient care. Increased awareness of these stressors should guide faculty support and development programs to ensure productive, stable faculty.

Adaptation, Psychological↗

Endoscopic anti-reflux devices: a year of challenges and change.

PURPOSE OF REVIEW: Endoscopic antireflux procedures have generated much interest among clinicians and patients. These devices utilize a variety of methods in an attempt to decrease reflux of gastric contents. This work reviews the most notable results of endoscopic antireflux procedure studies published in 2005. RECENT FINDINGS: A variety of studies of different technologies have been published this year. Only a few of these studies report data beyond 12 months to establish longer term efficacy. One sham controlled multicenter trial was published this year. After case reports of complications related to Enteryx (Boston Scientific Corp, Natick, Massachusetts, USA) use, this US Food and Drug Administration-approved device was voluntarily removed from the market. SUMMARY: A review of the literature demonstrates a paucity of long-term studies, as well as a lack of data comparing the devices to active medical therapy. The majority of studies are open-label trials with subjective endpoints, and such study designs are very susceptible to placebo effect. No one technology has demonstrated superiority to another. Additional studies with vigorous attention to methodology, safety evaluation, cost analysis and clinically meaningful endpoints will be required.

Endoscopes, Gastrointestinal↗

Does screening for Barrett's esophagus and adenocarcinoma of the esophagus prolong survival?

Despite the paucity of data supporting its use, screening upper endoscopy for patients with chronic gastroesophageal reflux disease symptoms to assess for Barrett's esophagus and esophageal adenocarcinoma has become a widely accepted practice. We apply the principles of screening to Barrett's esophagus and esophageal adenocarcinoma. Critical application of the key criteria of screening to this situation demonstrates that several criteria are unfulfilled. Key data are not available with which to judge other criteria. The major fault with screening for Barrett's esophagus is that the at-risk population is too broadly characterized and that too many cancers occur outside of this risk pool. Thus, recommendations for screening cannot be endorsed. Efforts may be better directed at further research identifying groups at risk for esophageal adenocarcinoma, developing more accurate and less-invasive methods of diagnosis, and discovering the underlying factors which continue to drive the increased incidence of this disease.

Adenocarcinoma↗

Pantoprazole reduces the size of postbanding ulcers after variceal band ligation: a randomized, controlled trial.

Elective esophageal variceal ligation (EVL) is performed to decrease the risk of variceal hemorrhage. Side effects of EVL include hemorrhage, chest pain, dysphagia, and odynophagia. Because gastric acid may exacerbate postbanding ulcers and delay healing, proton pump inhibition may decrease side effects associated with EVL. The aim of this study was to assess the efficacy of pantoprazole, a proton pump inhibitor, as an adjunct to elective EVL. We performed a double-blinded, randomized, placebo-controlled trial of pantoprazole after elective EVL. Subjects in the pantoprazole arm received 40 mg pantoprazole intravenously after EVL followed by 40 mg oral pantoprazole for 9 days. Control subjects received intravenous and oral placebo. Subjects underwent upper endoscopy 10 to 14 days after banding. Primary outcomes included the size and number of ulcers and the subjects' reports of dysphagia, chest pain, and heartburn. Forty-four subjects were randomized: 42 completed the protocol. At follow-up endoscopy, the mean number of ulcers was similar in the two groups. However, the ulcers in the pantoprazole group were on average half as large as in the placebo group (37 mm(2) vs. 82 mm(2), P < .01). Chest pain, dysphagia, and heartburn scores were not significantly different. Four subjects, all in the placebo group, had adverse outcomes, including 3 who bled from postbanding ulcers and 1 with sepsis. In conclusion, subjects receiving pantoprazole after elective EVL had significantly smaller postbanding ulcers on follow-up endoscopy than subjects receiving placebo. However, the total ulcer number and patient symptoms were not different between the groups.

2-Pyridinylmethylsulfinylbenzimidazoles↗

Factors influencing the shift of patients from one proton pump inhibitor to another: the effect of direct-to-consumer advertising.

BACKGROUND: Switching from one proton pump inhibitor (PPI) to another is common, and may be related to factors other than efficacy and tolerability. OBJECTIVES: The purposes of this study were to describe the incidence of therapeutic switching among PPI users, quantify direct ambulatory medical costs of switching, and characterize the relationship between product switching and variables hypothesized to influence a switch (eg, direct-to-consumer [DTC] advertising, structure of insurance coverage, disease diagnosis). METHODS: This was a retrospective cohort study of health plans using 1998 data. The subjects were employees and dependents with employer-sponsored health insurance contributing to the Medstat Market-Scan administrative dataset. Using a commercially available database to quantify DTC advertising by marketing area, market-specific expenditures were matched to eligible subjects. Among PPI users, we identified those who switched from one product to another (switchers) and compared their utilization and spending with nonswitchers. We then evaluated the relationship between drug use and variables hypothesized to affect switching: DTC advertising, insurance characteristics, patient diagnosis, diagnostic procedures, comorbidities, age, and sex. RESULTS: The analysis used data for 396,500 individuals from 47 unique markets that were geographically well distributed, with population density similar to that of the United States overall. The sample was also comparable with US census estimates for age and sex among working adults and their dependents. Only 620 (6.3%) of PPI users switched products during the 1998 calendar year. Annual diagnostic and drug costs were >US $400 higher for switchers than nonswitchers. Subjects in areas with high levels of DTC advertising were 43% more likely to switch from lansoprazole to omeprazole than those in the low-expenditure areas. Additionally, patients paying prescription drug copayments >US $5 were 12% less likely to switch from lansoprazole to omeprazole than patients paying lower copayments. CONCLUSIONS: In these privately insured patients using PPIs, product switching was associated with increased treatment costs. DTC advertising and patient cost-sharing were important predictors of product switching.

2-Pyridinylmethylsulfinylbenzimidazoles↗

The perception of cancer risk in patients with prevalent Barrett's esophagus enrolled in an endoscopic surveillance program.

BACKGROUND & AIMS: Patients with Barrett's esophagus (BE) have a risk of esophageal adenocarcinoma of approximately 0.5% per year. Patients may have difficulty understanding this risk. This study assessed the perceived risk of cancer in patients with BE, and correlated their risk estimates with their health care use behaviors. METHODS: We performed a survey of patients with BE participating in an endoscopic surveillance program at 2 sites: a university teaching hospital and a Veterans' Administration hospital. A questionnaire also elicited their demographics as well as their sources of health information. Health care behaviors, including physician visits and endoscopic surveillance behaviors, were assessed. Patients were classified as either overestimators or nonoverestimators of risk. Characteristics of overestimators, as well as health care use patterns, were assessed. RESULTS: One hundred eighteen patients met entry criteria, and 92 (78%) completed all the questionnaires. Sixty-eight percent of patients overestimated their 1-year risk of cancer, with a mean estimated 1-year cancer risk being 13.6%. The lifetime risk also was overestimated by 38% of patients. Patients who overestimated risk were more likely to be Veterans' Administration medical center patients, have more symptomatic reflux, and were more likely to use the Internet to get health care information. There was no significant difference in physician visits between overestimators and nonestimators (1.2 visits per year vs 1.0, P = .20), nor in endoscopy use (5.7 endoscopies per 5-year period vs 5.0, P = .42). CONCLUSIONS: The majority of patients with prevalent BE participating in an endoscopic surveillance program overestimated their chances of developing adenocarcinoma of the esophagus. Efforts to improve education of such patients with BE are warranted.

Adenocarcinoma↗