Development of a liver disease-specific large language model chat interface using retrieval-augmented generation.

BACKGROUND AND AIMS: Large language models (LLMs) have significant capabilities in clinical information processing tasks. Commercially available LLMs, however, are not optimized for clinical uses and are prone to generating hallucinatory information. Retrieval-augmented generation (RAG) is an enterprise architecture that allows the embedding of customized data into LLMs. This approach "specializes" the LLMs and is thought to reduce hallucinations. APPROACH AND RESULTS: We developed "LiVersa," a liver disease-specific LLM, by using our institution's protected health information-complaint text embedding and LLM platform, "Versa." We conducted RAG on 30 publicly available American Association for the Study of Liver Diseases guidance documents to be incorporated into LiVersa. We evaluated LiVersa's performance by conducting 2 rounds of testing. First, we compared LiVersa's outputs versus those of trainees from a previously published knowledge assessment. LiVersa answered all 10 questions correctly. Second, we asked 15 hepatologists to evaluate the outputs of 10 hepatology topic questions generated by LiVersa, OpenAI's ChatGPT 4, and Meta's Large Language Model Meta AI 2. LiVersa's outputs were more accurate but were rated less comprehensive and safe compared to those of ChatGPT 4. RESULTS: We evaluated LiVersa's performance by conducting 2 rounds of testing. First, we compared LiVersa's outputs versus those of trainees from a previously published knowledge assessment. LiVersa answered all 10 questions correctly. Second, we asked 15 hepatologists to evaluate the outputs of 10 hepatology topic questions generated by LiVersa, OpenAI's ChatGPT 4, and Meta's Large Language Model Meta AI 2. LiVersa's outputs were more accurate but were rated less comprehensive and safe compared to those of ChatGPT 4. CONCLUSIONS: In this demonstration, we built disease-specific and protected health information-compliant LLMs using RAG. While LiVersa demonstrated higher accuracy in answering questions related to hepatology, there were some deficiencies due to limitations set by the number of documents used for RAG. LiVersa will likely require further refinement before potential live deployment. The LiVersa prototype, however, is a proof of concept for utilizing RAG to customize LLMs for clinical use cases.

The association between mean arterial pressure and acute kidney injury reversal among decompensated cirrhosis patients.

BACKGROUND: This study informs how mean arterial pressure (MAP) impacts AKI recovery among all patients hospitalized with cirrhosis, regardless of etiology. METHODS: We identified incident AKI episodes among subjects in our cohort of decompensated cirrhosis patients. AKI was defined as a ≥50% increase in creatinine (sCr) from an outpatient baseline (≥7 days prior) that required hospitalization. Linear mixed-effects models were completed to determine the impact between AKI recovery, MAP, and time. To determine the impact of MAP on AKI reversal, we completed time-dependent Cox-regression models with time beginning at the time of peak sCr and ending at death, discharge, or AKI reversal, among those hospitalized with AKI and those with Persistent AKI (≥48 hours). RESULTS: We identified 702 hospitalized cirrhosis patients with AKI. We found those with AKI reversal had, on average, higher MAP (2.1 mmHg, p<0.05) and a greater increase in MAP over time (0.1 mmHg per hour, p<0.001). Among all 702 hospitalized patients with AKI and adjusted for confounders, each 5 mmHg increase in MAP was associated with 1.07x the hazard of AKI reversal (p<0.01). Similarly, among those with persistent AKI after adjusting for confounders, each 5 mmHg increase in MAP was associated with 1.19x greater likelihood of AKI reversal (p<0.001). Discussion: Our data demonstrate that MAP significantly increases the likelihood of AKI recovery regardless of severity or injury or AKI phenotype. We believe these data highlight the importance of MAP as a clinical tool to promote kidney function recovery among cirrhosis patients hospitalized with AKI.

Nutritional aspects of prehabilitation in adults with cirrhosis awaiting liver transplant.

Malnutrition, sarcopenia (low muscle mass), and physical frailty have gained increasing recognition in candidates for liver transplant (LT) as these conditions can impact postoperative functional capacity. Multidimensional prehabilitation programs have been proposed as a safe intervention in adults awaiting LT but the nutritional pillar of prehabilitation has been understudied. This review summarizes the nutritional recommendations for prehabilitation for individuals with cirrhosis awaiting LT. Three major aspects of nutritional prehabilitation are discussed: (1) Assess: Evaluate nutritional status and assess for malnutrition, sarcopenia, and frailty to guide the nutritional prehabilitation intervention intensity, increasing across universal, targeted, and specialist levels; (2) Intervene: Prescribe a nutritional prehabilitation intervention to meet established nutrition guidelines in cirrhosis with a targeted focus on improving nutritional status and muscle health; (3) Reassess: Follow-up based on the required intensity of nutritional care with as needed intervention adjustment. Topics covered in the review include nutritional care levels for prehabilitation, energy prescriptions across body mass index strata, detailed considerations around protein intake (amount, distribution, and quality), carbohydrate and fat intake, other nutritional considerations, and the potential role of dietary supplements and nutraceuticals. Future research is warranted to more accurately evaluate energy needs, evaluate emerging dietary supplementation strategies, and establish the role of nutraceuticals alongside food-based interventions. While the general principles of nutritional prehabilitation are ready for immediate application, future large-scale randomized controlled trials in this space will help to quantify the benefit that can be gained by transitioning the LT approach from passive "transplant waitlist time" to active "transplant preparation time."

Outpatient mean arterial pressure: A potentially modifiable risk for acute kidney injury and death among patients with cirrhosis.

Mean arterial blood pressure (MAP), which decreases as portal hypertension progresses, may be a modifiable risk factor among patients with cirrhosis. We included adults enrolled in the Functional Assessment in Liver Transplantation study. We completed latent class trajectory analyses to define MAP trajectories. We completed time-dependent Cox-regression analyses to test the association between outpatient MAP and 3 cirrhosis-related outcomes: (1) stage 2 acute kidney injury (AKI), defined as a ≥200% increase in serum creatinine from baseline; (2) a 5-point increase in the MELD-Na score, defined as the incidence of increase from initial MELD-Na; (3) waitlist mortality, defined as death on the waitlist. For each outcome, we defined MAP cut points by determining the maximally selected Log-rank statistic after univariable Cox-regression analyses. Among the 1786 patients included in this analysis, our latent class trajectory analyses identified 3 specific outpatient MAP trajectories: "stable-low," "stable-high," and "increasing-to-decreasing." However, >80% of patients were in a "stable-low" trajectory. We found in adjusted analyses that outpatient MAP was associated with each of our outcomes: Stage 2 AKI (adjusted hazard ratio 0.88 per 10 mm Hg increase in MAP [95% CI: 0.79-0.99]); 5-point increase in MELD-Na (adjusted hazard ratio: 0.91 [95% CI: 0.86-0.96]; waitlist mortality (adjusted hazard ratio: 0.89 [95% CI: 0.81-0.96]). For each outcome, we found that an outpatient MAP of 82 mm Hg was most associated with outcomes ( p <0.05 for all). Our study informs the association between outpatient MAP and cirrhosis-related outcomes. These findings, coupled with the identification of specific thresholds, lay the foundation for the trial of targeted outpatient MAP modulation in patients with cirrhosis.

Quality measures in pre-liver transplant care by the Practice Metrics Committee of the American Association for the Study of Liver Diseases.

INTRODUCTION: The LT evaluation and waitlisting process is subject to variations in care that can impede quality. The American Association for the Study of Liver Diseases (AASLD) Practice Metrics Committee (PMC) developed quality measures and patient-reported experience measures (PREMs) along the continuum of pre-LT care to reduce care variation and guide patient-centered care. METHODS: Following a systematic literature review, candidate pre-LT measures were grouped into four phases of care: referral, evaluation and waitlisting, waitlist management, and organ acceptance. A modified Delphi panel with content expertise in hepatology, transplant surgery, psychiatry, transplant infectious disease, palliative care and social work selected the final set. Candidate PREMs spanned domains of cognitive health, emotional health, social well-being, and understanding the LT process. RESULTS: Of the 71 candidate measures, 41 were selected: 9 for referral; 20 for evaluation and waitlisting; 7 for waitlist management; and 5 for organ acceptance. A total of 14 were related to structure, 17 were process measures and 10 were outcome measures that focused on elements not typically measured in routine care. Among the PREMs, LT candidates rated items from understanding the LT process domain as the most important. CONCLUSION: The proposed pre-LT measures provide a framework for quality improvement and care standardization among LT candidates. Select measures apply to various stakeholders such as referring practitioners in the community and LT centers. Clinically meaningful measures that are distinct from those used for regulatory transplant reporting may facilitate local QI initiatives to improve access and quality of care.

Financial burden following adult liver transplantation is common and associated with adverse recipient outcomes.

The financial impact of liver transplantation has been underexplored. We aimed to identify associations between high financial burden (≥10% annual income spent on out-of-pocket medical costs) and work productivity, financial distress (coping behaviors in response to the financial burden), and financial toxicity (health-related quality of life, HRQOL) among adult recipients of liver transplant. Between June 2021 and May 2022, we surveyed 207 adult recipients of liver transplant across 5 US transplant centers. Financial burden and distress were measured by 25 items adapted from national surveys of cancer survivors. Participants also completed the Work Productivity and Activity Impairment and EQ-5D-5L HRQOL questionnaires. In total, 23% of recipients reported high financial burden which was significantly associated with higher daily activity impairment (32.9% vs. 23.3%, p =0.048). In adjusted analyses, the high financial burden was significantly and independently associated with delayed or foregone medical care (adjusted odds ratio, 3.95; 95% CI, 1.85-8.42) and being unable to afford basic necessities (adjusted odds ratio, 5.12; 95% CI: 1.61-16.37). Recipients experiencing high financial burden had significantly lower self-reported HRQOL as measured by the EQ-5D-5L compared to recipients with low financial burden (67.8 vs. 76.1, p =0.008) and an age-matched and sex-matched US general population (67.8 vs. 79.1, p <0.001). In this multicenter cohort study, nearly 1 in 4 adult recipients of liver transplant experienced a high financial burden, which was significantly associated with delayed or foregone medical care and lower self-reported HRQOL. These findings underscore the need to evaluate and address the financial burden in this population before and after transplantation.

Applying human-centered design to the construction of a cirrhosis management clinical decision support system.

BACKGROUND: Electronic health record (EHR)-based clinical decision support is a scalable way to help standardize clinical care. Clinical decision support systems have not been extensively investigated in cirrhosis management. Human-centered design (HCD) is an approach that engages with potential users in intervention development. In this study, we applied HCD to design the features and interface for a clinical decision support system for cirrhosis management, called CirrhosisRx. METHODS: We conducted technical feasibility assessments to construct a visual blueprint that outlines the basic features of the interface. We then convened collaborative-design workshops with generalist and specialist clinicians. We elicited current workflows for cirrhosis management, assessed gaps in existing EHR systems, evaluated potential features, and refined the design prototype for CirrhosisRx. At the conclusion of each workshop, we analyzed recordings and transcripts. RESULTS: Workshop feedback showed that the aggregation of relevant clinical data into 6 cirrhosis decompensation domains (defined as common inpatient clinical scenarios) was the most important feature. Automatic inference of clinical events from EHR data, such as gastrointestinal bleeding from hemoglobin changes, was not accepted due to accuracy concerns. Visualizations for risk stratification scores were deemed not necessary. Lastly, the HCD co-design workshops allowed us to identify the target user population (generalists). CONCLUSIONS: This is one of the first applications of HCD to design the features and interface for an electronic intervention for cirrhosis management. The HCD process altered features, modified the design interface, and likely improved CirrhosisRx's overall usability. The finalized design for CirrhosisRx proceeded to development and production and will be tested for effectiveness in a pragmatic randomized controlled trial. This work provides a model for the creation of other EHR-based interventions in hepatology care.

Outcomes of High-Grade Immune Checkpoint Inhibitor Hepatitis in Hospitalized and Nonhospitalized Patients.

BACKGROUND & AIMS: Guidelines recommend hospitalization for severe immune checkpoint inhibitor (ICI) hepatitis. We compared patient outcomes in the inpatient versus outpatient settings. METHODS: We conducted a multicenter, retrospective cohort study of 294 ICI-treated patients who developed grade 3-4 ICI hepatitis. The primary outcome was time to alanine aminotransferase (ALT) normalization (≤40); secondary outcomes included time to ALT ≤100 U/L and time to death. To account for confounding by indication, inverse probability of treatment weighting was applied to perform Cox regression. A sensitivity analysis was performed excluding patients with grade 4 hepatitis. RESULTS: One hundred and sixty-six patients (56.5%) were hospitalized for a median of 6 (interquartile range, 3-11) days. On inverse probability of treatment weighting Cox regression, hospitalization was not associated with time to ALT normalization (hazard ratio [HR], 1.11; 95% confidence interval [CI], 0.86-1.43; P = .436) or time to ALT ≤100 U/L (HR, 1.11; 95% CI, 0.86-1.43; P = .420). In the sensitivity analysis limited to patients with grade 3 hepatitis, hospitalization was also not associated with time to ALT normalization (HR, 1.11; 95% CI, 0.83-1.50; P = .474) or time to ALT ≤100 U/L (HR, 1.19; 95% CI, 0.90-1.58; P = .225). In a subgroup analysis of 152 patients with melanoma, hospitalization was not associated with reduced risk of all-cause death (HR, 0.93; 95% CI, 0.53-1.64; P = .798). Notably, despite their Common Terminology Criteria for Adverse Events classification of high-grade hepatitis, 94% of patients had "mild" liver injury based on International Drug-Induced Liver Injury Criteria. CONCLUSIONS: Hospitalization of patients with high-grade ICI hepatitis was not associated with faster hepatitis resolution and did not affect mortality. Routine hospitalization may not be necessary in all patients with high-grade ICI hepatitis and Common Terminology Criteria for Adverse Events criteria may overestimate severity of liver injury.

Barriers and Facilitators to Exercise in Older Adults Awaiting Kidney Transplantation and Their Care Partners.

Rationale & Objective: Despite guidelines calling to improve physical activity in older adults, and evidence suggesting that prekidney transplant physical function is highly associated with posttransplant outcomes, only a small percentage of older patients treated with dialysis are engaged in structured exercise. We sought to elucidate barriers and facilitators of exercise among older adults treated with dialysis awaiting transplant and their care partners. Study Design: Individual, in-depth, cognitive interviews were conducted separately for patients and care partners through secure web-conferencing. Setting & Participants: Twenty-three patients (≥50 years of age, treated with dialysis from the University of San Francisco kidney transplantation clinic, with a short physical performance battery of ≤10) and their care partners. Analytical Approach: All audio interviews were transcribed verbatim. Three investigators independently coded data and performed qualitative thematic content. The interview guide was updated iteratively based on the Capability Opportunity Motivation Behavior model. Results: Patients' median age was 60 years (57 ± 63.5) and care partners' median ages was 57 years (49.5 ± 65.5). Thirty-nine percent of patients and 78% of care partners were female, 39% of patients and 30% of care partners self-identified as African American, and 47% of dyads were spouse or partner relationships. Major themes for barriers to pretransplant exercise included lack of understanding of an appropriate regimen, physical impairments, dialysis schedules, and safety concerns. Major facilitators included having individualized or structured exercise programs, increasing social support for patients and care partners, and motivation to regain independence or functionality or to promote successful transplantation. Limitations: Participants geographically limited to Northern California. Conclusions: Although patients and care partners report numerous barriers to pretransplant exercise and activity, they also reported many facilitators. An individualized, structured, home-based exercise program could circumvent many of the reported barriers and allow older patients to improve pretransplant physical function.

Although exercise can improve the fitness of older adults treated with dialysis for kidney transplantation and reduce posttransplant complications, many such individuals do not exercise. We sought to elicit perspectives on barriers and facilitators to prekidney transplant exercises from older adults treated with dialysis and their care partners. We found that although patients and care partners had unique perspectives, they shared many barriers (such as physical and/or cognitive impairment, difficulty scheduling around dialysis, lack of guidance on exercise, and reduced exercise motivation related to dialysis) and several facilitators (such as desire to regain functionality and participate in life and motivation for successful transplantation). A shared interest among patients and care partners in joint participation in structured and home-based exercise may represent a tool to overcome barriers to pretransplant exercise.

Association of biological aging with frailty and post-transplant outcomes among adults with cirrhosis.

Frailty is classically associated with advanced age but is also an important predictor of clinical outcomes in comparatively young adults with cirrhosis. We examined the association of biological aging with frailty and post-transplant outcomes in a pilot of adults with cirrhosis undergoing liver transplantation (LT). Frailty was measured via the Liver Frailty Index (LFI). The primary epigenetic clock DNA methylation (DNAm) PhenoAge was calculated from banked peripheral blood mononuclear cells; we secondarily explored two first-generation clocks (Hannum; Horvath) and two additional second-generation clocks (GrimAge; GrimAge2). Twelve adults were included: seven frail (LFI ≥ 4.4, mean age 55 years) and five robust (LFI < 3.2, mean age 55 years). Mean PhenoAge age acceleration (AgeAccel) was + 2.5 years (P = 0.23) for frail versus robust subjects. Mean PhenoAge AgeAccel was + 2.7 years (P = 0.19) for subjects who were readmitted or died within 30 days of discharge post-LT versus those without this outcome. When compared with first-generation clocks, the second-generation clocks demonstrated greater average AgeAccel for subjects with frailty or poor post-LT outcomes. Measuring biological age using DNAm-derived epigenetic clocks is feasible in adults undergoing LT. While frail and robust subjects had the same average chronological age, average biological age as measured by second-generation epigenetic clocks tended to be accelerated among those who were frail or experienced a poor post-LT outcome. These results suggest that frailty in these relatively young subjects with cirrhosis may involve similar aging mechanisms as frailty classically observed in chronologically older adults and warrant validation in a larger cohort.

A pragmatic tool to screen for pre-transplant cognitive impairment among potential candidates for liver transplant.

INTRODUCTION: Cognitive impairment (CI) among liver transplant (LT) candidates is associated with increased risk of waitlist mortality and inferior outcomes. While formal neurocognitive evaluation is the gold standard for CI diagnosis, the Montreal Cognitive Assessment (MoCA) is often used for first-line cognitive screening. However, MoCA requires specialized training and may be too lengthy for a busy evaluation appointment. An alternate approach may be the Quick Dementia Rating System (QDRS), which is patient- and informant-based and can be administered quickly. We compared potential LT candidates identified by MoCA and QDRS as potentially benefiting from further formal cognitive evaluation. METHODS: We identified 46 potential LT candidates enrolled at a single center of a prospective, observational cohort study who were administered MoCA and QDRS during transplant evaluation (12/2021-12/2022). Scores were dichotomized as (1) normal versus abnormal and (2) normal/mild impairment versus more-than-mild impairment. We calculated sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of QDRS compared to MoCA. RESULTS: By MoCA, this population had a prevalence of 48% normal cognition, 48% mild, 4% moderate, and 0% severe impairment. This was categorized as 96% normal/mild and 4% more-than-mild impairment. When comparing to MoCA cognitive screening, QDRS had a sensitivity of 61%, specificity of 56%, NPV of 56%, and PPV of 61%. When identifying more-than-mild impairment, QDRS had a sensitivity of 100%, specificity of 73%, NPV of 100%, and PPV of 10%. CONCLUSION: The high sensitivity and NPV of QDRS in identifying more-than-mild impairment suggests it could identify potential LT candidates who would benefit from further formal cognitive evaluation. The ability to administer QDRS quickly and remotely makes it a pragmatic option for pre-transplant screening.

Association between neighborhood-based material deprivation and liver transplant waitlist registrants demographics and mortality.

BACKGROUND & AIMS: Liver transplantation for alcohol-related liver disease (ARLD) has increased. We examined temporal trends in ARLD listing practices by neighborhood deprivation and evaluated the impact of neighborhood deprivation on waitlist mortality. METHODS: We included all adults > 18 years listed 2008-2019 in the UNOS registry. Our primary exposure was the neighborhood socioeconomic deprivation index based on patients' listing zip codes. We determined temporal trends in an ARLD listing diagnosis. We modeled ARLD listing diagnosis using logistic regression and waitlist mortality using Cox proportional hazards models. RESULTS: The waitlist contained an increasing proportion of patients listed with ARLD over the study period; however, this rate increased the least for patients from the most deprived tertile (p < .001). Patients from the most deprived tertile were the least likely to be listed with ARLD (OR: .97, 95CI: .95-.98). In our adjusted model, patients from the most deprived tertile had an increased hazard of waitlist mortality (OR: 1.10, 95CI: 1.06-1.14). CONCLUSION: Neighborhood deprivation was associated with a decreased likelihood of being listed with ARLD, suggesting that transplant for ARLD is inequitably available. The increased mortality associated with neighborhood deprivation demands future work to uncover the underlying reasons for this disparity.

Neighborhood Income Is Associated with Health Care Use in Pediatric Short Bowel Syndrome.

OBJECTIVE: To evaluate associations between neighborhood income and burden of hospitalizations for children with short bowel syndrome (SBS). STUDY DESIGN: We used the Pediatric Health Information System (PHIS) database to evaluate associations between neighborhood income and hospital readmissions, readmissions for central line-associated bloodstream infections (CLABSI), and hospital length of stay (LOS) for patients <18 years with SBS hospitalized between January 1, 2006, and October 1, 2015. We analyzed readmissions with recurrent event analysis and analyzed LOS with linear mixed effects modeling. We used a conceptual model to guide our multivariable analyses, adjusting for race, ethnicity, and insurance status. RESULTS: We included 4289 children with 16 347 hospitalizations from 43 institutions. Fifty-seven percent of the children were male, 21% were Black, 19% were Hispanic, and 67% had public insurance. In univariable analysis, children from low-income neighborhoods had a 38% increased risk for all-cause hospitalizations (rate ratio [RR] 1.38, 95% CI 1.10-1.72, P = .01), an 83% increased risk for CLABSI hospitalizations (RR 1.83, 95% CI 1.37-2.44, P < .001), and increased hospital LOS (ß 0.15, 95% CI 0.01-0.29, P = .04). In multivariable analysis, the association between low-income neighborhoods and elevated risk for CLABSI hospitalizations persisted (RR 1.70, 95% CI 1.23-2.35, P < .01, respectively). CONCLUSIONS: Children with SBS from low-income neighborhoods are at increased risk for hospitalizations due to CLABSI. Examination of specific household- and neighborhood-level factors contributing to this disparity may inform equity-based interventions.

Ambient air pollution is associated with graft failure/death in pediatric liver transplant recipients.

Children exposed to disproportionately higher levels of air pollution experience worse health outcomes. In this population-based, observational registry study, we examine the association between air pollution and graft failure/death in children following liver transplantation (LT) in the US. We modeled the associations between air pollution (PM2.5) levels localized to the patient's ZIP code at the time of transplant and graft failure or death using Cox proportional-hazards models in pediatric LT recipients aged <19 years in the US from 2005-2015. In univariable analysis, high neighborhood PM2.5 was associated with a 56% increased hazard of graft failure/death (HR: 1.56; 95% CI: 1.32, 1.83; P < .001). In multivariable analysis, high neighborhood PM2.5 was associated with a 54% increased risk of graft failure/death (HR: 1.54; 95% CI: 1.29, 1.83; P < .001) after adjusting for race as a proxy for racism, insurance status, rurality, and neighborhood socioeconomic deprivation. Children living in high air pollution neighborhoods have an increased risk of graft failure and death posttransplant, even after controlling for sociodemographic variables. Our findings add further evidence that air pollution contributes to adverse health outcomes for children posttransplant and lay the groundwork for future studies to evaluate underlying mechanisms linking PM2.5 to adverse LT outcomes.

Association of body mass index with post-liver transplant outcomes.

BACKGROUND: Patients with obesity have inferior outcomes after general surgery procedures, but studies evaluating post-liver transplant (LT) outcomes have been limited by small sample sizes or lack of granularity of outcomes. We evaluated the relationship between obesity and post-LT outcomes, including those observed in other populations to be obesity-related. METHODS: Included were 1357 LT recipients prospectively enrolled in the ambulatory pre-LT setting at 8 U.S. CENTERS: Recipient were categorized by body mass index (BMI, kg/m2 ): non-obese (BMI < 30), class 1 obesity (BMI 30-<35), and classes 2-3 obesity (BMI ≥ 35). Post-transplant complications were compared by BMI using Chi-square and rank-sum testing, logistic regression, Kaplan-Meier curves, and Cox regression. RESULTS: Classes 2-3 obesity was associated with higher adjusted odds than non-obesity of venous thrombosis [adjusted odds ratio (aOR) 2.06, 95% CI 1.01-4.23, p = .047] and wound dehiscence (aOR 2.45, 95% CI 1.19-5.06, p = .02). Compared with non-obese recipients, post-LT hospital stay was significantly longer for recipients with classes 2-3 obesity [p = .01; median (Q1-Q3) 9 (6-14) vs. 8 (6-12) days) or class 1 obesity [p = .002; 9 (6-14) vs. 8 (6-11) days].  Likelihood of ICU readmission, infection, discharge to a non-home facility, rejection, 30-day readmission, and 1-year readmission were similar across BMI categories (all p > .05). CONCLUSION: Compared to non-obese recipients, obese recipients had similar post-LT survival but longer hospital stay and higher likelihood of wound dehiscence and venous thrombosis. These findings underscore that obesity alone should not preclude LT, but recipients with obesity should be monitored for obesity-related complications such as wound dehiscence and venous thrombosis.

Brief PROMIS Assessment Screens for Frailty and Predicts Hospitalizations in Liver Transplant Candidates.

BACKGROUND: Frailty is prevalent in patients with end-stage liver disease and predicts waitlist mortality, posttransplant mortality, and frequency of hospitalizations. The Liver Frailty Index (LFI) is a validated measure of frailty in liver transplant (LT) candidates but requires an in-person assessment. METHODS: We studied the association between patient-reported physical function and LFI in a single-center prospective study of adult patients with cirrhosis undergoing LT evaluation from October 2020 to December 2021. Frailty was assessed with the LFI and 4-m gait speed. Patient-reported physical function was evaluated using a brief Patient-Reported Outcomes Measurement Information System (PROMIS) survey. RESULTS: Eighty-one LT candidates were enrolled, with a mean model of end-stage liver disease-sodium of 17.6 (±6.3). The mean LFI was 3.7 (±0.77; 15% frail and 59% prefrail) and the mean PROMIS Physical Function score was 45 (±8.6). PROMIS Physical Function correlated with LFI ( r = -0.54, P < 0.001) and 4-m gait speed ( r = 0.48, P < 0.001). The mean hospitalization rate was 1.1 d admitted per month. After adjusting for age, sex, and model of end-stage liver disease-sodium, patient-reported physical function-predicted hospitalization rate ( P = 0.001). CONCLUSIONS: This study suggests that a brief patient-reported outcome measure can be used to screen for frailty and predict hospitalizations in patients with cirrhosis.

The liver frailty index is a predictor of healthcare utilization after liver transplantation in older adults.

BACKGROUND: Older adults have higher healthcare utilization after liver transplantation (LT), yet objective risk stratification tools in this population are lacking. We evaluated the Liver Frailty Index (LFI) as one potential tool. METHODS: Ambulatory LT candidates ≥65 years without hepatocellular carcinoma (HCC) who underwent LT from 1/2012 to 6/2022 at 8 U.S. centers were included. Estimates of the difference in median using quantile regression were used to assess the adjusted association between LFI and hospitalized days within 90 days post-LT. RESULTS: Of 131 LT recipients, median (interquartile range [IQR]) (1st -3rd quartiles) age was 68 years (66-70); median pre-LT MELD-Na was 19 (15-24). Median LFI was 4.1 (3.6-4.7); 27% were frail (LFI≥4.5). Median hospitalized days within 90 days post-LT was 11 (7-20). Compared with non-frail patients, frail patients were hospitalized for a median of 5 days longer post-LT (95% CI .30-9.7, p = .04). Each .5 unit increase in pre-LT LFI was associated with an increase of 1.16 days (95%CI .42-2.69, p = .02) in hospitalized days post-LT. CONCLUSION: Among older adults undergoing LT, frailty was associated with more hospitalized days within 90 days after LT. The LFI can identify older adults who might benefit from pre-LT or early post-LT programs which may reduce post-LT healthcare utilization, such as early rehabilitation or post-hospital discharge programs.

Association of state Medicaid expansion policies with pediatric liver transplant outcomes.

Children from minoritized/socioeconomically deprived backgrounds suffer disproportionately high rates of uninsurance and graft failure/death after liver transplant. Medicaid expansion was developed to expand access to public insurance. Our objective was to characterize the impact of Medicaid expansion policies on long-term graft/patient survival after pediatric liver transplantation. All pediatric patients (<19 years) who received a liver transplant between January 1, 2005, and December 31, 2020 in the US were identified in the Scientific Registry of Transplant Recipients (N = 8489). Medicaid expansion was modeled as a time-varying exposure based on transplant and expansion dates. We used Cox proportional hazards models to evaluate the impact of Medicaid expansion on a composite outcome of graft failure/death over 10 years. As a sensitivity analysis, we conducted an intention-to-treat analysis from time of waitlisting to death (N = 1 1901). In multivariable analysis, Medicaid expansion was associated with a 30% decreased hazard of graft failure/death (hazard ratio, 0.70; 95% confidence interval, 0.62, 0.79; P < .001) after adjusting for Black race, public insurance, neighborhood deprivation, and living in a primary care shortage area. In intention-to-treat analyses, Medicaid expansion was associated with a 72% decreased hazard of patient death (hazard ratio, 0.28; 95% confidence interval, 0.23-0.35; P < .001). Policies that enable broader health insurance access may help improve outcomes and reduce disparities for children undergoing liver transplantation.

Prevalence of cognitive impairment in liver transplant recipients.

Liver transplant (LT) recipients have a high burden of cognitive impairment risk factors identified in other populations, yet little work has explored cognition in the United States LT population. We characterized prevalence of cognitive impairment (CI) in LT recipients pre-LT and ≥3 months post-LT. Adult LT recipients with cirrhosis but without active pre-LT hepatic encephalopathy (HE) were screened for CI using the Montreal Cognitive Assessment (MoCA) for CI (MoCA <24) both pre-LT and ≥3 months post-LT. The association between cognitive performance and recipient characteristics was assessed using logistic regression. Of 107 LT recipients, 36% had pre-LT CI and 27% had post-LT CI [median (Q1-Q3) MoCA 26 (23-28)]. Each 1-point increase in pre-LT MoCA was associated with 26% lower odds of post-LT cognitive impairment (aOR .74, 95% CI .63-.87, p < .001), after adjusting for recipient age, history of HE, and time since LT. In this study of cirrhosis recipients without active pre-LT HE, cognitive impairment was prevalent before LT and remained prevalent ≥3 months after LT (27%), long after effects of portal hypertension on cognition would be expected to have resolved. Our data expose an urgent need for more comprehensive neurologic examination of LT recipients to better identify, characterize, and address predictors of post-LT cognitive impairment.