Low-Income, Poor Physical Health, Poor Mental Health, and Other Social Risk Factors Are Associated With Decreased Access to Care in Patients With Carpal Tunnel Syndrome.

BACKGROUND: Carpal Tunnel Syndrome (CTS) is associated with a significant personal and societal burden. Evaluating access to care can identify barriers, limitations, and disparities in the delivery of healthcare services in this population. The purpose of this study was to evaluate access to overall healthcare and healthcare utilization among patients with CTS. METHODS: This is a retrospective cohort study conducted with the All of Us database. Patients diagnosed with CTS that completed the access to care survey were included and matched to a control group. The primary outcomes were access to care across 4 domains: (1) delayed care, (2) could not afford care, (3) skipped medications, and (4) over 1 year since seeing provider. Secondary analysis was then performed to identify patient-specific factors associated with reduced access to care. RESULTS: In total, 7649 patients with CTS were included and control matched to 7649 patients without CTS. In the CTS group, 33.7% (n = 2577) had delayed care, 30.4% (n = 2323) could not afford care, 15.4% (n = 1180) skipped medications, and 1.6% (n = 123) had not seen a provider in more than 1 year. Within the CTS cohort, low-income, worse physical health, and worse mental health were associated with poor access to care. CONCLUSION: Patients experience notable challenges with delayed care, affordability of care, and medication adherence regardless of having a diagnosis of CTS. Targeted interventions on modifiable risk factors such as low income, poor mental health, and poor physical health are important opportunities to improve access to care in this population.

Strains/Sprains and Fractures Are the Most Common Hand and Wrist Injuries in National Basketball Association Athletes Who Return to Preinjury Player Efficiency and Equal or Greater True Shooting Percentage Within Two Years of Injury.

Purpose: To characterize the prevalence and incidence of in-game hand and wrist injuries in the National Basketball Association (NBA), to determine the factors associated with an equal or greater player efficiency rating (PER), and to determine the factors associated with an equal or greater true shooting percentage (TS%) 2 years after a hand and wrist injury using a large-scale national database of NBA players. Methods: Injury data from seasons 2015-2016 to 2020-2021, with exclusion of the 2019-2020 because of abbreviated play due to the coronavirus disease 2019, were extracted from a public online database, Pro Sports Transactions. Injury characteristics and NBA player demographic information were assessed using descriptive statistics. Poisson logistic regression analyses were performed to identify risk factors associated with equal or increased PER and TS% 2years after injury. Results: There were 214 reported hand and wrist injuries, and of these injuries, 173 (81%) were classified as structural. The most common injury types were a strain or sprain (0.63 per 1,000 game exposures), followed by fractures (0.37 per 1,000 game exposures). Older age (relative risk [RR] 0.89; 95% confidence interval [CI] 0.84-0.95) and more years played in the NBA were modestly associated with relative risk of having a decreased PER at 2 years after injury. Increased weight (RR 1.02; 95% CI 1-1.05) and increased body mass index (RR 1.14; 95% CI 1.01-1.29) were also modestly associated with having a decreased PER and TS%, respectively at 2 years after injury. Conclusions: Strains/sprains and fractures are the most common hand and wrist injuries sustained by NBA players. Regardless of dominant or nondominant hand and wrist injuries, NBA players are likely to return to baseline overall player efficiency based on PER and TS% within 2 years of injury. Clinical Relevance: Our study characterizes hand and wrist injuries of NBA players and provides an understanding for these injuries on player performance at 2 years.

Musculofascial Z-Lengthening for the Management of Chronic Medial Epicondylitis: Technique and Early Results.

Medial epicondylitis is a common elbow pathology secondary to flexor-pronator tendinosis associated with repetitive wrist flexion activities. Though often responsive to nonoperative management, recalcitrant symptomatology is not uncommon. Surgical intervention for chronic medial epicondylitis most commonly involves open debridement of degenerative tendon which can be difficulty to identify and with a notably risk of iatrogenic complication. We present a reproducible musculofascial z-lengthening of the flexor-pronator mass for management of chronic medial epicondylitis and report the mid-term results of this intervention.

Rare Bipolaris Species Fungal Periprosthetic Hip Infection in an Immunocompetent Host: A Case Report.

CASE: We present a case report of a 64-year-old man who developed a rare Bipolaris species fungal periprosthetic joint infection (PJI) after revision arthroplasty for complications associated with a metal-on-metal total hip arthroplasty. The patient underwent a 2-stage debridement with antibiotic bead placement and implant retention, along with chronic antifungal suppression. At the 2-year follow-up, the patient remained asymptomatic. CONCLUSION: Fungal PJI with filamentous fungi such as Bipolaris species is a rare clinical entity. This case report highlights the clinical presentation and management of this rare condition.

Decoding the Signals: An Analysis of Preference Signaling in the 2023 Orthopaedic Surgery Residency Match.

Background: While previously used in other specialties, the preference signaling program (PSP) was implemented in the 2022 to 2023 orthopaedic surgery residency application process for the first time. The PSP allowed for 30 signaling tokens to be sent by applicants to programs of their choice to indicate particular interest in a program. It remains unknown how the PSP affects applicants and programs in the orthopaedic surgery residency match. Thus, this study's purpose was to assess the utility of preference signaling within the orthopaedic surgery residency application process in its inaugural year of use. Methods: An anonymous electronic survey was emailed to all orthopaedic surgery residency applicants who applied to the authors' institution during the 2022 to 2023 application cycle. The survey was sent after match lists were submitted and closed before the release of match results. The survey collected information regarding applicant demographics, preference signaling habits, and attitude toward preference signaling. Results: The survey was completed by 101 applicants. Applicants applied to a mean of 90 programs (range: 10-197) and received an average of 12 interview invitations (range: 0-39). Applicants almost uniformly used all 30 signals, with nearly two-thirds signaling their home programs (65%, 49/76), and nearly all applicants sending signals to programs at which they performed away rotations (95.7%, 88/92). Applicants received a mean of 9 invitations from programs they signaled, compared with 2 invitations from programs they did not signal. Applicants were significantly more likely to receive an interview invite at a program they signaled than one they did not (p < 0.01). Overall, 57% of applicants (57/101) found the PSP to be helpful, whereas 28% (28/101) found it to be unhelpful, and 16% (16/101) had a neutral opinion. Conclusions: This study reports that the PSP in the 2022 to 2023 orthopaedic surgery match was an effective method of expressing interest in a program because applicants were significantly more likely to receive interview invites to signaled programs. More than half of respondents felt PSP to be helpful; however, the effect on application numbers is still unclear. Level of Evidence: III.

Deep learning based phenotyping of medical images improves power for gene discovery of complex disease.

Electronic health records are often incomplete, reducing the power of genetic association studies. For some diseases, such as knee osteoarthritis where the routine course of diagnosis involves an X-ray, image-based phenotyping offers an alternate and unbiased way to ascertain disease cases. We investigated this by training a deep-learning model to ascertain knee osteoarthritis cases from knee DXA scans that achieved clinician-level performance. Using our model, we identified 1931 (178%) more cases than currently diagnosed in the health record. Individuals diagnosed as cases by our model had higher rates of self-reported knee pain, for longer durations and with increased severity compared to control individuals. We trained another deep-learning model to measure the knee joint space width, a quantitative phenotype linked to knee osteoarthritis severity. In performing genetic association analysis, we found that use of a quantitative measure improved the number of genome-wide significant loci we discovered by an order of magnitude compared with our binary model of cases and controls despite the two phenotypes being highly genetically correlated. In addition we discovered associations between our quantitative measure of knee osteoarthritis and increased risk of adult fractures- a leading cause of injury-related death in older individuals-, illustrating the capability of image-based phenotyping to reveal epidemiological associations not captured in the electronic health record. For diseases with radiographic diagnosis, our results demonstrate the potential for using deep learning to phenotype at biobank scale, improving power for both genetic and epidemiological association analysis.

Association of Unmet Social Needs With Level of Capability in People With Persistent Knee Pain.

BACKGROUND: Musculoskeletal providers are increasingly recognizing the importance of social factors and their association with health outcomes as they aim to develop more comprehensive models of care delivery. Such factors may account for some of the unexplained variation between pathophysiology and level of pain intensity and incapability experienced by people with common conditions, such as persistent nontraumatic knee pain secondary to osteoarthritis (OA). Although the association of one's social position (for example, income, employment, or education) with levels of pain and capability are often assessed in OA research, the relationship between aspects of social context (or unmet social needs) and such symptomatic and functional outcomes in persistent knee pain are less clear. QUESTIONS/PURPOSES: (1) Are unmet social needs associated with the level of capability in patients experiencing persistently painful nontraumatic knee conditions, accounting for sociodemographic factors? (2) Do unmet health-related social needs correlate with self-reported quality of life? METHODS: We performed a prospective, cross-sectional study between January 2021 and August 2021 at a university academic medical center providing comprehensive care for patients with persistent lower extremity joint pain secondary to nontraumatic conditions such as age-related knee OA. A final 125 patients were included (mean age 62 ± 10 years, 65% [81 of 125] women, 47% [59 of 125] identifying as White race, 36% [45 of 125] as Hispanic or Latino, and 48% [60 of 125] with safety-net insurance or Medicaid). We measured patient-reported outcomes of knee capability (Knee injury and Osteoarthritis Outcome Score for Joint Replacement), quality of life (Patient-Reported Outcome Measure Information System [PROMIS] Global Physical Health and PROMIS Global Mental Health), and unmet social needs (Accountable Health Communities Health-Related Social Needs Survey, accounting for insufficiencies related to housing, food, transportation, utilities, and interpersonal violence), as well as demographic factors. RESULTS: After controlling for demographic factors such as insurance status, education attained, and household income, we found that reduced knee-specific capability was moderately associated with experiencing unmet social needs (including food insecurity, housing instability, transportation needs, utility needs, or interpersonal safety) (standardized beta regression coefficient [ß] = -4.8 [95% confidence interval -7.9 to -1.7]; p = 0.002 and substantially associated with unemployment (ß = -13 [95% CI -23 to -3.8]; p = 0.006); better knee-specific capability was substantially associated with having Medicare insurance (ß = 12 [95% CI 0.78 to 23]; p = 0.04). After accounting for factors such as insurance status, education attained, and household income, we found that older age was associated with better general mental health (ß = 0.20 [95% CI 0.0031 to 0.39]; p = 0.047) and with better physical health (ß = 0.004 [95% CI 0.0001 to 0.008]; p = 0.04), but effect sizes were small to negligible, respectively. CONCLUSION: There is an association of unmet social needs with level of capability and unemployment in patients with persistent nontraumatic knee pain. This finding signals a need for comprehensive care delivery for patients with persistent knee pain that screens for and responds to potentially modifiable social risk factors, including those based on one's social circumstances and context, to achieve better outcomes. LEVEL OF EVIDENCE: Level II, prognostic study.

Imposter Syndrome Among Surgeons Is Associated With Intolerance of Uncertainty and Lower Confidence in Problem Solving.

BACKGROUND: Feelings of imposter syndrome (inadequacy or incompetence) are common among physicians and are associated with diminished joy in practice. Identification of modifiable factors associated with feelings of imposter syndrome might inform strategies to ameliorate them. To this point, though, no such factors have been identified. QUESTION/PURPOSE: Are intolerance of uncertainty and confidence in problem-solving skills independently associated with feelings of imposter syndrome after accounting for other factors? METHODS: This survey-based experiment measured the relationship between feelings of imposter syndrome, intolerance of uncertainty, and confidence in problem-solving skills among musculoskeletal specialist surgeons. Approximately 200 surgeons who actively participate in the Science of Variation Group, a collaboration of mainly orthopaedic surgeons specializing in upper extremity illnesses primarily across Europe and North America, were invited to this survey-based experiment. One hundred two surgeons completed questionnaires measuring feelings of imposter syndrome (an adaptation of the Clance Imposter Phenomenon Scale), tolerance of uncertainty (the Intolerance of Uncertainty Scale-12), and confidence in problem-solving skills (the Personal Optimism and Self-Efficacy Optimism questionnaire), as well as basic demographics. The participants were characteristic of other Science of Variation Group experiments: the mean age was 52 ± 5 years, with 89% (91 of 102) being men, most self-reported White race (81% [83 of 102]), largely subspecializing in hand and/or wrist surgery (73% [74 of 102]), and with just over half of the group (54% [55 of 102]) having greater than 11 years of experience. We sought to identify factors associated with greater feelings of imposter syndrome in a multivariable statistical model. RESULTS: Accounting for potential confounding factors such as years of experience or supervision of trainees in the multivariable linear regression analysis, greater feelings of imposter syndrome were modestly associated with higher intolerance of uncertainty (regression coefficient [ß] 0.34 [95% confidence interval (CI) 0.16 to 0.51]; p < 0.01) and with lower confidence in problem-solving skills (ß -0.70 [95% CI -1.0 to -0.35]; p < 0.01). CONCLUSION: The finding that feelings of imposter syndrome may be modestly to notably associated with modifiable factors, such as difficulty managing uncertainty and lack of confidence in problem-solving, spark coaching opportunities to support and sustain a surgeon's mindset, which may lead to increased comfort and joy at work. CLINICAL RELEVANCE: Beginning with premedical coursework and throughout medical training and continuing medical education, future studies can address the impact of learning and practicing tactics that increase comfort with uncertainty and greater confidence in problem solving on limiting feelings of imposter syndrome.

Does Value-Based Care Threaten Joint Arthroplasty Access for Vulnerable Patient Populations?: AOA Critical Issues.

ABSTRACT: Health-care expenses have been projected to increase from 17.7% of the U.S. gross domestic product (GDP) in 2014 to 19.6% in 2024. The unsustainable increase in health-care costs has contributed toward support for value-based health care (VBHC) reform. Contemporary VBHC reform programs relevant to orthopaedic surgery include the voluntary Bundled Payments for Care Improvement initiatives (BPCI and BPCI-Advanced) and the Comprehensive Care for Joint Replacement (CJR) program, a mandatory bundled payment program.The purported benefits of transitioning from volume-based reimbursement to value-based reimbursement include moving from a fragmented provider-centered care model to a patient-centered model, with greater care coordination and alignment among providers focused on improving value. VBHC models allow innovative strategies to proactively invest resources to promote value (e.g., the use of nurse navigators) while eliminating unnecessary resources that do not promote value. However, major concerns regarding VBHC include the absence of medical and socioeconomic risk stratification as well as decreased access for higher-risk patients.This article identifies the benefits and potential unintended consequences of VBHC reform, with a focus on joint arthroplasty. We also discuss some potential strategies to promote innovation and improve value without compromising access for vulnerable patients.

Incorporating patient-reported outcomes into shared decision-making in the management of patients with osteoarthritis of the knee: a hybrid effectiveness-implementation study protocol.

INTRODUCTION: Osteoarthritis (OA) is a major clinical and public health concern. The primary surgical treatment of knee OA is total knee replacement (TKR), a procedure that aims to alleviate pain and restore physical function. TKR is expensive, however, and based on professional guidelines, inappropriately performed in up to a third of patients. Patient-reported outcome measures (PROMs) help evaluate treatment options by quantifying health outcomes that matter to patients and can thus inform shared decision-making (SDM) between patients and health professionals. METHODS AND ANALYSIS: This is a US-based 2-year, two-site hybrid type 1 study to assess clinical effectiveness and implementation of a machine learning-based patient decision aid (PDA) integrating patient-reported outcomes and clinical variables to support SDM for patients with knee OA considering TKR. Substudy 1: At one study site, a randomised controlled trial is evaluating the clinical effectiveness of the PDA and SDM process on decision quality as measured after the baseline consultation and treatment choice measured 3 and 6 months after the baseline visit among 200 patients with knee OA. Substudy 2: At a second study site, a qualitative assessment using principles of behaviour design and intervention mapping is evaluating the feasibility and acceptability of the PROMs, PDA and SDM process by interviewing seven health professionals and 25 patients before and 25 patients after PDA implementation. ETHICS AND DISSEMINATION: Ethics approval has been obtained from The University of Texas at Austin Institutional Review Board (protocol number: 2018-11-0042). Informed consent will be obtained from all participants. Study results will be disseminated through conference presentations, publications and professional societies. TRIAL REGISTRATION NUMBER: NCT04805554.

Patient and Surgeon Ratings of Patient Involvement in Decision-Making Are Not Aligned.

BACKGROUND: Specialists want to guide patients toward making informed treatment choices consistent with what matters most to them (their values). One measure of this goal is alignment between patient and surgeon-perceived involvement in decision-making. We performed a cross-sectional survey of patients presenting for musculoskeletal specialty care to determine agreement between patients and surgeons regarding patient involvement in shared decision-making. We also tested (1) factors associated with specialist-perceived involvement, accounting for the patient's perceived involvement in decision-making, and (2) factors associated with patient perception of involvement in decision-making, accounting for ratings of preferred involvement. METHODS: In this cross-sectional survey, 136 patients seeking musculoskeletal care for conditions involving the upper or lower extremities rated their preferred level of involvement in decision-making (Control Preferences Scale) before the visit and their perceived level of involvement (Modified Control Preferences Scale) after the visit. Participants also completed measures of symptoms of depression and pain self-efficacy. After the visit, the surgeons rated their perception of the patient's involvement in decision-making (Modified Control Preferences Scale). RESULTS: There was poor agreement between patients and surgeons regarding the extent of patient participation in decision-making (ICC = 0.11). The median difference was 1 point on a 5-point Likert scale (interquartile range: 0 to 1). Accounting for demographic characteristics and personal factors in multivariable analysis, specialists rated patients who did not have a high school diploma as having less involvement in decision-making. Specialist-perceived patient involvement in decision-making was not related to patient-perceived involvement. The only factor associated with higher patient-rated involvement was higher patient-preferred involvement (OR = 3.9; 95% CI = 2.6 to 5.8; p < 0.001). CONCLUSIONS: The observation that surgeons misperceive patient participation in decision-making emphasizes the need for strategies to ensure patient participation, such as methods to help patients gain awareness of what matters most to them (their values), clinician checklists for identification and reorientation of common misinterpretations of symptoms, and decision aids or motivational interviewing tools that can help to ensure that patient choices are consistent with their values and are unhindered by misconceptions.

Digital Phenotyping and Patient-Generated Health Data for Outcome Measurement in Surgical Care: A Scoping Review.

Digital phenotyping-the moment-by-moment quantification of human phenotypes in situ using data related to activity, behavior, and communications, from personal digital devices, such as smart phones and wearables-has been gaining interest. Personalized health information captured within free-living settings using such technologies may better enable the application of patient-generated health data (PGHD) to provide patient-centered care. The primary objective of this scoping review is to characterize the application of digital phenotyping and digitally captured active and passive PGHD for outcome measurement in surgical care. Secondarily, we synthesize the body of evidence to define specific areas for further work. We performed a systematic search of four bibliographic databases using terms related to "digital phenotyping and PGHD," "outcome measurement," and "surgical care" with no date limits. We registered the study (Open Science Framework), followed strict inclusion/exclusion criteria, performed screening, extraction, and synthesis of results in line with the PRISMA Extension for Scoping Reviews. A total of 224 studies were included. Published studies have accelerated in the last 5 years, originating in 29 countries (mostly from the USA, n = 74, 33%), featuring original prospective work (n = 149, 66%). Studies spanned 14 specialties, most commonly orthopedic surgery (n = 129, 58%), and had a postoperative focus (n = 210, 94%). Most of the work involved research-grade wearables (n = 130, 58%), prioritizing the capture of activity (n = 165, 74%) and biometric data (n = 100, 45%), with a view to providing a tracking/monitoring function (n = 115, 51%) for the management of surgical patients. Opportunities exist for further work across surgical specialties involving smartphones, communications data, comparison with patient-reported outcome measures (PROMs), applications focusing on prediction of outcomes, monitoring, risk profiling, shared decision making, and surgical optimization. The rapidly evolving state of the art in digital phenotyping and capture of PGHD offers exciting prospects for outcome measurement in surgical care pending further work and consideration related to clinical care, technology, and implementation.

Compilation and Analysis of Web-Based Orthopedic Personalized Predictive Tools: A Scoping Review.

Web-based personalized predictive tools in orthopedic surgery are becoming more widely available. Despite rising numbers of these tools, many orthopedic surgeons may not know what tools are available, how these tools were developed, and how they can be utilized. The aim of this scoping review is to compile and synthesize the profile of existing web-based orthopedic tools. We conducted two separate PubMed searches-one a broad search and the second a more targeted one involving high impact journals-with the aim of comprehensively identifying all existing tools. These articles were then screened for functional tool URLs, methods regarding the tool's creation, and general inputs and outputs required for the tool to function. We identified 57 articles, which yielded 31 unique web-based tools. These tools involved various orthopedic conditions (e.g., fractures, osteoarthritis, musculoskeletal neoplasias); interventions (e.g., fracture fixation, total joint arthroplasty); outcomes (e.g., mortality, clinical outcomes). This scoping review highlights the availability and utility of a vast array of web-based personalized predictive tools for orthopedic surgeons. Increased awareness and access to these tools may allow for better decision support, surgical planning, post-operative expectation management, and improved shared decision-making.

Immunization with cytolethal distending toxin B produces autoantibodies to vinculin and small bowel bacterial changes in a rat model of postinfectious irritable bowel syndrome.

BACKGROUND: Recent data substantiate the importance of acute gastroenteritis in the development of irritable bowel syndrome (IBS). An animal model of postinfectious IBS determined the importance of cytolethal distending toxin B (CdtB) during live Campylobacter jejuni infection and its development of autoimmunity to vinculin. In this study, we examine whether subcutaneous exposure to CdtB alone is sufficient to produce the postinfectious IBS effect and autoimmunity. METHODS: Sixty adult Sprague Dawley rats were randomized into 2 groups to receive subcutaneous injection of either CdtB or vehicle and administered a booster injection of the same product 3 weeks later. Serum was collected for anti-CdtB and anti-vinculin titers. Duodenal and ileal luminal contents for total eubacterial qPCR, and ileal bowel segments were harvested for vinculin and ileal expression. In a second experiment, 4 adult, Sprague Dawley rats were injected with either Cy7-labeled anti-CdtB and anti-vinculin antibodies were injected into the tail vein and imaged to determine organ localization of the antibodies. KEY RESULTS: Rats that received CdtB increased in serum anti-CdtB after injection. CdtB exposure also precipitated significant elevation in anti-vinculin antibodies (P < .001). This was associated with a reduction in intestinal vinculin expression (P < .001) that negatively correlated with serum anti-CdtB levels. CdtB exposure was also associated with greater levels of duodenal (P < .001) and ileal (P < .01) bacteria by qPCR that positively correlated with anti-CdtB levels. CONCLUSIONS AND INFERENCES: Rats injected with CdtB developed a postinfectious IBS-like phenotype and autoimmunity to vinculin with corresponding reduction in intestinal vinculin expression.

Breath Test Gas Patterns in Inflammatory Bowel Disease with Concomitant Irritable Bowel Syndrome-Like Symptoms: A Controlled Large-Scale Database Linkage Analysis.

INTRODUCTION: Breath testing (BT) has gained interest for diagnosing small intestinal bacterial overgrowth (SIBO) in IBD patients with irritable bowel syndrome (IBS) overlap. We aim to characterize the rate of SIBO and BT gas patterns in IBD patients with IBS-like symptoms compared to non-IBD patients. METHODS: A database of 14,847 consecutive lactulose BTs was developed from patients with IBS-like symptoms between November 2005 and October 2013. BTs were classified as normal, H2 predominant, CH4 predominant, and flatline based on criteria established from the literature. BT data linkage with electronic health records and chart review identified IBD patients along with disease phenotype, location, severity, and antibiotic response. Poisson loglinear model evaluated differences in gas patterns between the two groups. RESULTS: After excluding patients with repeat breath tests, we identified 486 IBD and 10,505 non-IBD patients with at least one BT. Positive BT was present in 57% (n = 264) of IBD patients. Crohn's disease (odds ratio (OR) 0.21, [95% confidence interval (CI) 0.11-0.38]) and ulcerative colitis (OR 0.39, [95% CI 0.22-0.70]) patients were less likely to produce excess CH4. IBD patients were more likely to have flatline BT (OR 1.82, [95% CI 1.20-2.77]). In IBD patients with SIBO, 57% improved symptomatically with antibiotics. CONCLUSION: In a cohort of IBD patients with IBS-like symptoms, a high rate of patients had positive BT and symptomatic improvement with antibiotics. In IBD, methanogenesis is suppressed and flatline BT is more frequent, suggesting excess hydrogenotrophic bacteria. These findings suggest methanogenic and hydrogenotrophic microorganisms as potential targets for microbiome-driven biomarkers and therapies.

Declining Rates of Referral for Irritable Bowel Syndrome Without Constipation at a Tertiary Care Center.

BACKGROUND: Irritable bowel syndrome (IBS) is a common chronic disorder of the gastrointestinal tract. Several treatments have been developed, including rifaximin for the treatment of IBS without constipation (non-IBS-C), but no studies have evaluated the effect of these therapies on patient referral rates to tertiary care gastroenterology clinics. AIM: To assess referral patterns for IBS patients at a tertiary motility clinic over a 10-year period. METHODS: Data from consecutive patients referred to the clinic during 2006-2016 were analyzed. Trends in the proportion of referrals and prior rifaximin use in IBS-C versus non-IBS-C groups were compared. RESULTS: A total of 814 adult patients were referred to a single physician panel for IBS-related symptoms. Of these, 776 were included in the study [528 females (68%), average age 45.7 ± 15.9 years), comprising 431 IBS-C (55.5%) and 345 non-IBS-C (44.5%) patients. The proportion of non-IBS-C referrals declined significantly from 53.0% in 2006 to 27.3% in 2016 (Chi-square, p < 0.0001, Cochran-Armitage trend test p = 0.0001), and the proportion of IBS-C referrals increased significantly from 46.9% in 2006 to 72.7% in 2016 (Chi-square, p < 0.0001, Cochran-Armitage trend test p = 0.0004). Non-IBS-C referrals with prior rifaximin use significantly increased from 22.7% in 2006 to 66.7% in 2016 (Cochran-Armitage trend test, p = 0.008). CONCLUSIONS: The results indicate a significantly declining tertiary care referral rate for non-IBS-C over the past decade. While not directly linked, there has been an increase in rifaximin use in the same population during the same time interval.

Biomarkers of Irritable Bowel Syndrome.

Traditionally, irritable bowel syndrome (IBS) has not been regarded as an organic disease, and the pathophysiology of IBS is heterogeneous. Currently, the diagnosis of IBS is based upon the Rome diagnostic criteria. The performance of these criteria is only modest in predicting IBS, and moreover their validation is lacking. Additionally, as functional symptoms are common in the general population, healthy controls or volunteers are difficult to define and there is currently no definition of "normal" in the Rome criteria. Due to the weaknesses of the current diagnostic criteria, patients and doctors expect new gold standard diagnostic tools. Various etiologic mechanisms result in potential biomarkers. The focus of this research has been to find non-invasive biomarkers from serum, breath gas, and fecal materials. Though biomarkers should be based on biological and pathogenic processes, most biomarkers for IBS have been developed to identify organic diseases and therefore eliminate IBS. To date, these types of biomarkers for IBS have been disappointing. The purposes of developing biomarkers include improvement of diagnosis, differentiation from other organic diseases, and discrimination of IBS subtypes. A true mechanistic biomarker would make it possible to rule in IBS, rather than to rule out other organic diseases. New serologic biomarkers for diarrhea-predominant IBS have been introduced based on the pathophysiologic findings from a rat model and validation in a large-scale clinical trial. Further investigations of abnormal organic findings from each subtype of IBS would enable the development of new, simple subtype-specific biomarkers.

Intestinal methane production is associated with decreased weight loss following bariatric surgery.

To determine whether methane and hydrogen on breath test affects weight loss after bariatric surgery, 156 subjects (pre-surgery BMI ≥33) were recruited ≥4 months after surgery. Pre- and post-surgery weights and BMIs were recorded. Post-surgery methane and hydrogen levels were determined. % total weight loss and % change in BMI were prorated to six months after surgery. M+/H+ subjects (N=13) exhibited lower prorated % change in BMI vs. all other subjects (N=144) (p=0.13), and significantly lower prorated % total weight loss (p=0.036). These findings may suggest that subjects with positive breath methane and hydrogen lose less weight following bariatric surgery.