Laurence F. McMahon

Systematic review: effects of resident work hours on patient safety

Key Summary Points The Accreditation Council for Graduate Medical Education has mandated work hour limitations for all residents in the United States. Evidence about patient safety is insufficient to inform the process of reducing resident work hours. Seven studies have assessed patient safety and interventions to decrease resident work hours. Previous research on interventions to reduce resident work hours is suboptimal and contradictory (some studies suggest improvements in patient safety indicators, while other studies suggest no change or possible harm after interventions were performed). Future research should focus on patient safety indicators as outcomes when interventions to decrease resident work hours are implemented. Several national organizations, including Public Citizen (a consumer watchdog group) (1), the American Medical Student Association (AMSA) (2), and the Committee of Interns and Residents (CIR) (3), have criticized the long hours of residency. Together, these groups unsuccessfully petitioned the Occupational Safety and Health Administration (OSHA) to require resident work hour limitations (1). Some patient safety advocates believe that limiting physician work hours and decreasing fatigue will improve patient safety (4). This widely accepted belief has led to dramatic reform initiated by the Accreditation Council for Graduate Medical Education (ACGME) (5). This reform sought to create a minimum standard for duty hours across all training programs, regardless of specialty. This change occurred nationally on 1 July 2003 (6). The effect of this universal change in resident work hours on patient safety is unknown. A primary concern with the modification of resident work hours is the potential loss of continuity of care (7, 8). Continuity is a core value across specialties, and its preservation has potential benefits and drawbacks for patients, physicians, and the health care system. The trade-off between the positive values of continuity of care and decreasing resident fatigue has important implications for patient safety, both directly (for example, errors) and indirectly (for example, resident health). It is unclear how solutions that provide resident night-float coverage and improve resident mood and satisfaction will affect patient care. The predictable consequence of decreasing hours of care is that multiple physicians must now care for an individual patient; the consequence to patient safety of these several patient hand-offs is unknown. It is difficult to know how to achieve an optimal balance between continuity and fatigue, given that both may have repercussions for patient safety and are optimized in different ways. In the past year, residency programs in all specialties have been investing time and resources to conform to the ACGMEs regulations. While the proposed changes to resident work hours have been much debated (7-12), a systematic review of the literature examining the relationship between limiting resident work hours and patient safety will help inform this discussion and guide policymakers (13), program directors, and others who are involved in educating residents. Methods Data Sources We searched the English-language literature about resident work hours for 1966 to March 2004 with MEDLINE, PREMEDLINE (1966 to mid-2002 only), EMBASE, and Current Contents. In March 2004, we re-ran the MEDLINE, EMBASE, and Current Contents searches by using the same strategy. The MEDLINE search was conducted by exploding and combining the following Medical Subject Heading (MeSH) terms: workload; work schedule tolerance; fatigue; mental fatigue; sleep; sleep deprivation; sleep disorders; sleep disorder, circadian rhythm; chronobiology; and personnel staffing and scheduling. We included the following terms in a keyword search: work hours, workload, fatigue, and work schedule. We combined all the keywords and MeSH subheadings. Finally, we combined that list with the combination of the exploded MeSH term education, medical, graduate, and the term internship and residency. The keyword night float was searched separately. We used similar search strategies with the other databases. The list contained more than 1300 references. We hand-searched several journals that are not indexed for 1966 to 2002: Medical Teacher (19791986), Medical Education (19761986), British Journal of Medical Education (19661975), and Teaching and Learning in Medicine (19892002). We also hand-searched several journals (Annals of Internal Medicine, Academic Medicine, Society of General Internal Medicine, Journal of the American Medical Association, and The New England Journal of Medicine) for January to March 2004 to ensure that important relevant articles that were not yet indexed would be included. We identified 8 additional studies of interventions to limit resident work hours. One of these studies reported patient safetyrelated outcomes. We examined the reference lists of all articles included in our review and the reference lists of review articles to identify additional papers. Finally, we asked an expert to review our final bibliography to ensure the completeness of the list of relevant published and unpublished studies. Study Selection We included studies that 1) assessed a system change designed to counteract the effects of work hours, fatigue, or sleep deprivation and 2) included an outcome directly related to patient safety (for example, death, morbidity, and patient care errors). Starting with more than 1200 citations for 1966 to 2002 and 172 citations for 2002 to 2004, we reviewed the abstracts of all relevant articles (Figure). Of these, 343 warranted more detailed review to determine whether they met inclusion criteria (many of the original citations were not research reports). Two authors involved in data abstraction independently reviewed the articles from the first search to ascertain whether they met inclusion criteria. One author reviewed the articles from the second search by using the same inclusion criteria. Figure. The process used to search the literature and select studies for inclusion. Data Abstraction Of the 343 papers reviewed, 42 studies described relevant interventions, and 11 of those evaluated patient outcomes. We eliminated 2 studies because they relied solely on survey reports of errors (1 resident self-report [14] and 1 report of nurses perceptions of resident errors [15]). We eliminated 2 other papers because they studied patient satisfaction, not safety (16, 17). Thus, we included 7 studies in this review. Two authors abstracted the data from each included article, and 1 author reviewed all studies. We used a standardized abstraction form that included the following information: number of participants, presence or absence of a control group, study design, outcomes, and methodologic concerns. We resolved all disagreements by discussion and consensus. When necessary, we attempted to contact the authors of the studies to provide additional information. Role of the Funding Source The Ann Arbor Veterans Affairs Medical Center/University of Michigans Patient Safety Enhancement Program had no role in the design, conduct, or reporting of the study or in the decision to submit the manuscript for publication. Data Synthesis We present the results of the 7 intervention studies that assessed patient safety outcomes. The Appendix Table shows the study design, strengths, and weaknesses of each study. No study was a clinical trial. The Table summarizes the studies diverse interventions. The outcomes also varied considerably from study to study (Table). To clarify our terminology, we use interns to refer to physicians in their first year of postgraduate training and residents for those in at least their second year of postgraduate training. Table. Summary of the Studies Included in the Review: Interventions and Outcomes Appendix Table. Summary of Study Design Strengths and Weaknesses Daigler and colleagues (18) conducted a retrospective cohort study to assess the effect of schedule changes for interns in a pediatrics program that would result in compliance with New York code 405 (the New York state law that limited resident work hours in 1989 [25]). In the preintervention period (19871988), residents worked approximately 100 hours per week and took overnight call every third or fourth night. In the postintervention period (19881989), the interns were scheduled to work less than 70 hours per week. Each week had one 24-hour day, one 16-hour day, one 12-hour day, three 9-hour days, and one day off. The intensive care units continued to have call every third night. The authors reported no difference in mortality, morbidity, or unexpected intensive care unit transfers after the schedule changes occurred. However, this study is flawed because the methods section contains very limited information about the patient sample, data collection, and data analysis. Gottlieb and colleagues (19) used a prospective prepost design to evaluate the effects of schedule changes in an internal medicine program at a Veterans Affairs hospital. These changes consisted of shifting from a call system with interns on call every fourth night and residents on call every eighth night to a system that incorporated a night- float system. The teams in the new system had 7-day cycles with 1 long call day, 3 short call days, and 3 noncall days during each cycle. Short call also occurred on the weekends. Therefore, interns were on call overnight every seventh night while residents were on call overnight every 14th night. Night-float teams admitted all patients after 10 p.m. on Sunday to Thursday. The housestaff reported sleeping substantially more after the intervention (19). The patient-related outcomes studied were medication errors, fevers, deaths, and readmissions. Resource utilization was also studied in the form of length of stay and the numbers of laboratory tests, consultations, and radiographs ordered. Statistically significantly

Racial and gender variation in use of diagnostic colonic procedures in the Michigan Medicare population.

BACKGROUNDnThere is accumulating evidence that screening programs can alter the natural history of colorectal cancer, a significant cause of mortality and morbidity in the US. Understanding how the technology to diagnose colonic diseases is utilized in the population provides insight into both the access and processes of care.nnnMETHODnUsing Medicare Part B billing files from the state of Michigan from 1986 to 1989 we identified all procedures used to diagnose colorectal disease. We utilized the Medicare Beneficiary File and the Area Resource File to identify beneficiary-specific and community-sociodemographic characteristics. The beneficiary and sociodemographic characteristics were, then, used in multiple regression analyses to identify their association with procedure utilization.nnnRESULTSnSigmoidoscopic use declined dramatically with the increasing age cohorts of Medicare beneficiaries. Urban areas and communities with higher education levels had more sigmoidoscopic use. Among procedures used to examine the entire colon, isolated barium enema was used more frequently in African Americans, the elderly, and females. The combination of barium enema and sigmoidoscopy was used more frequently among females and the newest technology, colonoscopy, was used most frequently among White males.nnnCONCLUSIONnThe existence of race, gender, and socioeconomic disparities in the use of colorectal technologies in a group of patients with near-universal insurance coverage demonstrates the necessity of understanding the reason(s) for these observed differences to improve access to appropriate technologies to all segments in our society.

Evaluating the Care of General Medicine Inpatients: How Good Is Implicit Review?

Review of the medical record is an integral part of evaluating the quality and appropriateness of inpatient care (for example, by payers, hospitals, professional organizations, and researchers) [1-4]. Often the initial review of the patients charts is based on predetermined criteria (explicit review) and does not require a physician reviewer. However, the complexity and heterogeneity of care on general medicine services makes it impractical to develop valid preset criteria for most aspects of care provided on these services [1, 2]. Therefore, most quality and utilization review for general medical inpatients relies on the opinions of peers as to whether they believe the care was appropriate (implicit review). Structured implicit review is a process whereby an expert reviewer judges specific aspects of patient care [1, 3, 5]. By serially focusing the reviewers attention on important aspects of care and by obtaining implicit judgments about this care, the reliability and the validity of the review are improved. This process was pioneered by Butler and Quinlan [6] and has been refined by researchers at the RAND Corporation [3, 5, 7] for specific medical diseases. Concurrent with our study, Rubin and colleagues [8] independently developed a structured, implicit review instrument for diverse medical and surgical conditions. Implicit review by peers (structured or not) is generally considered the community standard for final quality decisions [3, 4]. However, given that practice norms vary widely, can peers agree on the bounds of appropriate care? A recent review [9] of the literature found a paucity of empiric information about the reliability of peer judgments. Little information has been reported on the reliability of peers judgments about most aspects of care for general medicine inpatients (for example, specific quality problems and appropriateness of resource use). We evaluated implicit review for measuring quality of care and appropriateness of resource use on general medicine wards. We determined how often poor care was identified, the types of reported quality problems, and the level of agreement between different physician reviewers (inter-rater reliability). Methods Patients All patients were in one of four general medicine services at a large university teaching hospital. Each ward team consisted of an attending physician, a resident, and two or three interns, who rotated on the service for 1 month. The patient mix was heterogeneous; no single diagnostic-related group contributed more than 5% of patient admissions. A review of a random sample of admissions, occurring from January 1988 to June 1990, was supplemented with oversampling of patient groups of particular interest; deaths, those having readmission within 28 days of discharge, and patients who had an increase in their APACHE-L score (a severity-of-illness measure composed of the laboratory section of the original APACHE score) [10] during hospitalization. We also sampled patients for whom hospital satisfaction data were available (a survey of consecutive patients discharged alive during a 6-month period). Overall, charts from 675 patient admissions were reviewed (5% of charts selected for review could not be obtained for review): 425 patient admissions were selected randomly with replacement and 250 patient admissions were selected randomly to oversample deaths, early readmissions, in-hospital increases in APACHE-L scores, and the patient satisfaction survey. This sampling strategy was designed to allow for detailed analysis of patient groups of special interest for an evaluation of quality screens and of the impact of a clinical management intervention. Approximately 20% of charts from patient admissions (n = 171) were randomly selected for multiple independent reviews to allow for reliability testing. Although reviewers knew that the completeness and reliability of their reviews were being tested, they did not know which patients had their charts selected for multiple reviews. The 12 reviewers worked varying numbers of hours on the study and are not equally represented in the reliability analyses. However, all but one reviewer reviewed between 25 to 45 of the 171 patient admission charts selected for multiple reviews. The remaining reviewer dropped out of the study early on and reviewed only nine of the reliability charts. Excluding this reviewer from the analyses would not affect our results. The 171 patient admissions selected for inter-rater reliability testing of the reviewers had a mean age of 52 years (SD, 20 years), 20% of patients died in the hospital (as mentioned above, deaths were oversampled), and they were from 39 different diagnostic-related groups (no more than 12 patient admissions were in any one diagnostic-related group). The median number of reviewers per case was three. Structured Implicit Review Instrument Using the knowledge gained from structured implicit review for specific medical diseases, we developed a structured, implicit review instrument to evaluate quality of care on a general medicine ward. This instrument included 10 questions about specific aspects of the quality of inpatient care, 5 questions about the appropriateness of resource use, and 3 questions about outpatient care before admission. For patients who died in the hospital, reviewers were asked if their deaths were preventable by better quality of care. The overall evaluation of quality of medical care was rated on a 6-point scale (1 = superior, 2 = excellent, 3 = good, 4 = adequate, 5 = substandard, 6 = poor). Most of the other items were measured on 5-point scales (for example, 1 = definitely adequate, 2 = probably adequate, 3 = unsure, 4 = probably not adequate, 5 = definitely not adequate). For all measures, more appropriate care was represented by a lower scale score. When reviewers were unsure, they were asked to explain the reason for their uncertainty (borderline medical care was provided, handwriting illegible, inadequate documentation in the chart, or other). Reviews were done by 12 board-certified internists (7 fellows and 5 faculty) who had reputations for being excellent clinicians at the study hospital. All reviewers had recent or current extensive experience in general medicine inpatient care and had trained in diverse settings; only four had trained at the study hospital. All reviewers had 15 to 20 hours of training before beginning chart review. In a 90-minute initial instruction session, we reviewed the abstracting form and written instructions for completion of the implicit review process. Reviewers were given examples of what we considered substantial and unimportant deviations from standard of care for each item on the review form. We discussed the possible effect of poor outcomes on a reviewers judgment [12]. Reviewers were instructed not to second-guess reasonable judgments using hindsight and to concentrate on the quality of the process of care. They were asked to evaluate whether they believed the care received was appropriate, regardless of whether the patient had a good or bad outcome. We were only interested in clinically important quality problems that put the patient at substantial risk of a poor outcome. Each reviewer was required to give a written description of any alleged quality problem and to record the specific risk for the patient. Reviewers were not to consider inefficient care or unnecessary use of hospital resources in their evaluation of overall quality, unless it resulted in undue patient risk (for example, an unnecessary angiogram). After the initial training session, all reviewers were assigned to review the same 15 to 20 pilot charts. Small group meetings, with three to four reviewers, were then held to discuss their ratings of these patient admission charts for each category of the chart-review instrument. The instructions given in the original meeting were reiterated in detail. Then preliminary assessments of the reviewers reliability and thoroughness were evaluated, and 4 of the 12 reviewer trainees were assigned more pilot charts for additional training. Once chart review had begun in earnest, reviewers could still direct questions about the review form to the chart review supervisor (RAH). This supervisor examined reviewers written comments and abstract forms to check for inconsistencies or incomplete data and contacted reviewers when necessary. Every 2 months the supervisor (RAH) contacted all chart reviewers. He asked the reviewers if they were having any problems with the reviews and reinforced training (by reviewing the definitions of the review instrument subcategories and reiterating the training instructions). Copies of the review instrument and the instructions to reviewers are available on request. Statistical Analysis Weighted statistics were calculated to quantify the inter-rater reliabilities of reviewers implicit judgments. Kappas were calculated on 171 charts that had multiple reviews producing 368 separate comparisons. In evaluating inter-rater reliabilities, it is important to distinguish between reliabilities necessary for assessment of each patient and those needed for assessment of an aggregate of patients. For most aggregate comparisons using means or proportions (such as comparing mean scores on two hospital wards), moderate reliabilities of 0.5 or 0.6 are usually acceptable [11]. However, reliabilities must often be high to make a confident assessment of each patient ( 0.80) [11]. However, the statistic is only a summary of the amount of agreement and does not directly relay the predictiveness of a judgment. Therefore, we calculated the sensitivity and specificity of a single review using the mean review of the other reviewers as the standard (using a method described by Rubin and colleagues [8]). This analysis estimates the likelihood that a single review would correctly classify the patient compared with multiple other reviews (cutoff point for substandard care was a mean s

Variation in hospital admissions among small areas: A comparison of Maine and Michigan

Analysis of age-adjusted hospital admission profiles among small geographic areas has shown marked variation in hospital admissions for both surgical and medical cases in areas ranging from Maine to Manitoba. Much of the work has been led by John Wennberg and has focused on rural areas. This study examines the degree of variation in hospital admissions in small areas in the state of Michigan to determine whether those diseases that demonstrated high variation in Maine also demonstrated the same degree of variation in Michigan. The data on the degree of variation in 111 modified diagnosis-related groups (M-DRGs) from the state of maine were supplied by Dr. Wennberg. Using the same M-DRGs, we defined age-adjusted, population-based hospital admission rates for the lower peninsula of Michigan for 1980 among 60 previously defined hospital marked communities. The observed hospital discharge counts in each of the M-DRGs were compared to the expected counts in each of the 60 communities, where the expected count was based on an indirect age adjustment. Both the Maine and Michigan small area data were expressed by the M-DRGs systematic standard deviation in which random variation has been accounted for via a Poisson probability model. It was found that the systematic standard deviations of the M-DRGs in Maine and the M-DRGs in Michigan strongly correlated with a spearman correlation coefficient Of 0.71 (P <0.001). This study demonstrates that across a variety of geographic areas with differing mixes of urban, suburban, and rural locations there is remarkable consistency among diagnostic groups that show a high degree of variation in hospital admissions and those that show a low degree of variation. These data are encouraging; they suggest that an analysis of the reasons for small area variation in one area may be transportable to others.

Prediction of barrett's esophagus among men

OBJECTIVES:Risk factors for Barretts esophagus include gastroesophageal reflux disease (GERD) symptoms, age, abdominal obesity, and tobacco use. We aimed to develop a tool using these factors to predict the presence of Barretts esophagus.METHODS:Male colorectal cancer (CRC) screenees were recruited to undergo upper endoscopy, identifying newly diagnosed cases of Barretts esophagus. Logistic regression models predicting Barretts esophagus using GERD symptoms alone and together with abdominal obesity, tobacco use, and age were compared.RESULTS:Barretts esophagus was found in 70 (8.5%) of 822 CRC screenees. Mutually adjusting for other covariates, Barretts esophagus was associated with weekly GERD (odds ratio (OR)=2.33, 95% confidence interval (CI)=1.34, 4.05), age (OR per 10 years=1.53, 95% CI=1.05, 2.25), waist-to-hip ratio (OR per 0.10=1.44, 95% CI=0.898, 2.32) and pack-years of cigarette use (OR per 10 pack-years=1.09, 95% CI=1.04, 1.14). A model including those four factors had a greater area under the receiver operating characteristics curve than did a model based on GERD frequency and duration alone (0.72 vs. 0.61, P<0.001), and it had a net reclassification improvement index of 19–25%.CONCLUSIONS:The prevalence of Barretts esophagus was substantial in our population of older overweight men. A model based on GERD, age, abdominal obesity, and cigarette use more accurately classified the presence of Barretts esophagus than did a model based on GERD alone. Following validation of the tool in another population, its use in clinical practice might improve the efficiency of screening for Barretts esophagus.

Hospital-Acquired Catheter-Associated Urinary Tract Infection: Documentation and Coding Issues May Reduce Financial Impact of Medicare's New Payment Policy •

OBJECTIVEnTo evaluate whether hospital-acquired catheter-associated urinary tract infections (CA-UTIs) are accurately documented in discharge records with the use of International Classification of Diseases, Ninth Revision, Clinical Modification diagnosis codes so that nonpayment is triggered, as mandated by the Centers for Medicare and Medicaid Services (CMS) Hospital-Acquired Conditions Initiative.nnnMETHODSnWe conducted a retrospective medical record review of 80 randomly selected adult discharges from May 2006 through September 2007 from the University of Michigan Health System (UMHS) with secondary-diagnosis urinary tract infections (UTIs). One physician-abstractor reviewed each record to categorize UTIs as catheter associated and/or hospital acquired; these results (considered gold standard) were compared with diagnosis codes assigned by hospital coders. Annual use of the catheter association code (996.64) by UMHS coders was compared with state and US rates by using Healthcare Cost and Utilization Project data.nnnRESULTSnPatient mean age was 58 years; 56 (70%) were women; median length of hospital stay was 6 days; 50 patients (62%) used urinary catheters during hospitalization. Hospital coders had listed 20 secondary-diagnosis UTIs (25%) as hospital acquired, whereas physician-abstractors indicated that 37 (46%) were hospital acquired. Hospital coders had identified no CA-UTIs (code 996.64 was never used), whereas physician-abstractors identified 36 CA-UTIs (45%; 28 hospital acquired and 8 present on admission). Catheter use often was evident only from nursing notes, which, unlike physician notes, cannot be used by coders to assign discharge codes. State and US annual rates of 996.64 coding (approximately 1% of secondary-diagnosis UTIs) were similar to those at UMHS.nnnCONCLUSIONSnHospital coders rarely use the catheter association code needed to identify CA-UTI among secondary-diagnosis UTIs. Coders often listed a UTI as present on admission, although the medical record indicated that it was hospital acquired. Because coding of hospital-acquired CA-UTI seems to be fraught with error, nonpayment according to CMS policy may not reliably occur.

The Risk-Adjusted Mortality Index. A new measure of hospital performance.

The Commission on Professional and Hospital Activities (CPHA) developed the Risk-Adjusted Mortality Index (RAMI), a method for comparing hospital death rates using existing abstract or billing data. The method is comprehensive insofar as it includes all payers and all types of cases except neonates. RAMI was designed to differentiate among admissions on the basis of the patient characteristics that increase or reduce the risk of dying in the hospital. Using a large national data base, risk factors were determined empirically within each of 310 clusters based on diagnosis-related groups (DRGs). The model was very effective at predicting risk-adjusted outcomes, with a correlation of 0.98 between actual and predicted deaths in a sample of 300 hospitals. RAMI appears to be a powerful tool for using existing data to monitor changes over time in hospital death rates.

Measuring hospital performance. The development and validation of risk-adjusted indexes of mortality, readmissions, and complications.

In this study we used information from discharge abstracts to develop three different risk-adjusted measures of hospital performance: a Risk-Adjusted Mortality Index, a Risk-Adjusted Readmissions Index, and a Risk-Adjusted Complications Index. The adjustments have face validity, and appear to account for much of the variation across hospitals in the rates of these adverse events. The indexes are stable over time, and are not biased with respect to hospital size, ownership, or teaching status. All three indexes appear to have construct validity when tested against the changes in hospital care that occurred when PPS was introduced.

Small-area Variation in Hospital Discharge Rates: Do Socioeconomic Variables Matter?

Although numerous studies have been made of the determinants of smallarea variation in hospital discharge rates, there is still disagreement about the role of socioeconomic factors. The lack of consensus stems, in part, from the difficulty in comparing results across studies that use different units and methods of analysis. Many of the studies using well-defined hospital service areas did not have the data needed to conduct a controlled analysis of the determinants of hospital utilization. Most of the studies that have performed controlled analyses have relied on larger geopolitical areas, which are not believed to capture self-contained health care systems. The study described here used a consistent set of data, three methods of analysis, and two units of analysis to test the importance of socioeconomic characteristics in explaining the variation in medical and surgical discharge rates in Michigan. Socioeconomic factors are found to be statistically significant determinants of the variation in both medical and surgical discharge rates, whether the method of analysis is simple correlations or multiple regressions, and whether the unit of analysis is the county or a well-designed hospital service area. These results suggest that previous small-area variation studies may have incorrectly concluded that socioeconomic characteristics do not explain differences in utilization rates.

A Pilot Study of the Association of Low Plasma Adiponectin and Barrett's Esophagus

BACKGROUND AND AIMS:Gastroesophageal reflux disease (GERD) and obesity are associated with esophageal adenocarcinoma (EAC). We hypothesized that the obesity–EAC relation is mediated by factors secreted from adipocytes. Adiponectin is a peptide secreted by adipocytes, and its plasma levels are inversely associated with obesity. We aimed to estimate the effect of circulating adiponectin on the risk of Barretts esophagus (BE), an accepted precursor of EAC, controlling for GERD symptoms and other potential confounders.METHODS:We conducted a case–control study in cases of BE compared with controls without BE; most controls had GERD. Odds ratios (OR), corresponding to associations with BE, were estimated from conditional and unconditional logistic regression analyses of 50 matched pairs.RESULTS:BE was inversely associated with plasma adiponectin level (OR for each 10-μg/mL decrement 4.7, 95% confidence interval [CI] 1.4–15.0) and positively associated with GERD duration ≥10 yr, male gender, tobacco smoking, body mass index (BMI), waist circumference, and waist-to-hip ratio. Further adjustment for GERD duration, tobacco use, and BMI increased the adiponectin–BE association (OR 6.4, 95% CI 1.1–37.0), but the estimated OR was reduced when adjusting for measures of abdominal obesity (e.g., OR 2.5, 95% CI 0.49–13.00) and further adjusting for gender (OR 1.8, 95% CI 0.66–4.70).CONCLUSIONS:Despite methodologic limitations, including the small sample size, our findings suggest that adiponectin may be involved in the etiology of BE. Rather than simply a mechanical effect of obesity promoting GERD, the effects of abdominal obesity on the risk of BE might be mediated by adiponectin and other circulating factors.