Evaluating Receipt of Optimal Medical Therapy Amongst Structurally Disadvantaged Groups Undergoing Amputation.

OBJECTIVES: Optimal medical therapy (OMT) for peripheral artery disease (PAD) is associated with decreased major amputation and mortality. OMT has several components, including antiplatelet and high-intensity statin therapy, blood pressure control, etc. While there are disparities in receipt of OMT among PAD patients, it is unknown if patients from disadvantaged neighborhoods, measured by the area deprivation index (ADI), are less likely to be on OMT. METHODS: We performed a retrospective review of patients that underwent major lower extremity amputation between 2015 and 2019 at two large academic healthcare systems. Primary exposure was high ADI, defined as ADI ≥60th percentile, and secondary exposure was non-Hispanic Black (NHB) race. For each analysis, the primary outcome of interest was receipt of OMT, defined here as at least one antiplatelet agent and a high-intensity statin. The exposure outcome relationship was assessed using multivariable logistic regression. RESULTS: Among 354 patients with median age of 66 (interquartile range [IQR] 58-74), 267 (75.4%) were male, 219 (61.9%) identified as NHB and 116 (32.8%) as non-Hispanic White. Overall, 91 (25.7%) patients were on OMT at time of amputation despite 57.3% of the cohort being established with a vascular surgeon. Compared to those with low ADI, the category high ADI had a higher proportion of NHB patients (48.1% vs 70.3%, p= 0.001) and patients were more often hospitalized at the University-affiliated facilities (47.4% vs 63.0%, p= 0.004). High ADI was not associated with receipt of OMT prior to major amputation (adjusted odds ratio [aOR] 0.72, 95% confidence interval [CI] 0.42-1.24). In secondary analysis, NHB race was not associated with receipt of OMT. Stratification by facility type (Veterans Affairs and University-affiliated facilities) also showed no association between high ADI or race and receipt of OMT. CONCLUSIONS: Neighborhood economic well-being is not associated with receipt of OMT prior to major amputation. While the absence of socioeconomic disparities is notable, the proportion of patients on OMT is suboptimal. Care processes should be critically evaluated and quality measures potentially created to improve the rate of receipt of OMT among patients at risk for amputation.

Accuracy and consistency of publicly available Large Language Models as clinical decision support tools for the management of colon cancer.

BACKGROUND: Large Language Models (LLM; e.g., ChatGPT) may be used to assist clinicians and form the basis of future clinical decision support (CDS) for colon cancer. The objectives of this study were to (1) evaluate the response accuracy of two LLM-powered interfaces in identifying guideline-based care in simulated clinical scenarios and (2) define response variation between and within LLMs. METHODS: Clinical scenarios with "next steps in management" queries were developed based on National Comprehensive Cancer Network guidelines. Prompts were entered into OpenAI ChatGPT and Microsoft Copilot in independent sessions, yielding four responses per scenario. Responses were compared to clinician-developed responses and assessed for accuracy, consistency, and verbosity. RESULTS: Across 108 responses to 27 prompts, both platforms yielded completely correct responses to 36% of scenarios (n = 39). For ChatGPT, 39% (n = 21) were missing information and 24% (n = 14) contained inaccurate/misleading information. Copilot performed similarly, with 37% (n = 20) having missing information and 28% (n = 15) containing inaccurate/misleading information (p = 0.96). Clinician responses were significantly shorter (34 ± 15.5 words) than both ChatGPT (251 ± 86 words) and Copilot (271 ± 67 words; both p < 0.01). CONCLUSIONS: Publicly available LLM applications often provide verbose responses with vague or inaccurate information regarding colon cancer management. Significant optimization is required before use in formal CDS.

Setting reasonable goals for kidney transplant referral among dialysis facilities.

BACKGROUND: Determining whether a patient is eligible for kidney transplantation is complex. In this study, we estimate what proportion of patients with end-stage kidney disease (ESKD) might have been suitable candidates for kidney transplantation but were not referred. METHODS: We identified 43,952 people initiating dialysis for kidney failure between 2012 and 2017 in the states of Georgia, North Carolina, or South Carolina from the United States Renal Data System and linked to the Early-Steps to Transplant Access Registry to obtain data on referral and waitlisting up until December 2020. We identified 'good transplant candidates' as those who were waitlisted within 2-years of referral, among all patients referred within 1-year of dialysis initiation. Using propensity score cut-offs, logistic regression, and area under the curve (AUC), we then estimated the proportion of individuals who may have been good transplant candidates, but were not referred. RESULTS: Overall, 42.6% of incident dialysis patients were referred within one year and among them, 32.9% were waitlisted within 2 years of referral. Our model had reasonably good discrimination for identifying good transplant candidates with an AUC of 0.70 (95%CI 0.69-0.71), sensitivity of 0.68 and specificity of 0.61. Overall, 25% of individuals not referred for transplant may have been 'good' transplant candidates. Adding these patients to the existing 18,725 referred patients would increase the proportion of incident ESKD patients being referred within one year from 42.6% to 57.2% (a ~ 14.6% increase). CONCLUSIONS: In this study, we show that a significant proportion of potentially good transplant candidates are not being referred for transplant. A ~ 14% increase in the proportion of patients being referred from dialysis facilities is both a meaningful and realistic goal and could lead to more qualified patients being referred and subsequently waitlisted for a lifesaving transplant.

Sex/Gender Disparities in Preemptive Referrals for Kidney Transplantation.

Introduction: Sex/gender inequities persist in access to kidney transplantation. Whether differences in preemptive referral (i.e., referral before dialysis start) explain this inequity remains unknown. Methods: All adults (aged 18-79 years; N = 44,204) initiating kidney replacement therapy (KRT; dialysis or transplant) in Georgia (GA), North Carolina (NC), or South Carolina (SC) between 2015 and 2019 were identified from the United States Renal Data System (USRDS). Individuals were linked to the Early Steps to Kidney Transplant Access Registry (E-STAR) to obtain data on preemptive referral and followed-up with through November 13, 2020, for outcomes of waitlisting and living donor transplant. Logistic regression assessed the association between sex/gender and likelihood of preemptive referral among all KRT patients. Cox-proportional hazards assessed the association between sex/gender and waitlisting or living donor among preemptively referred patients. Results: Overall, men and women were similarly likely to be preemptively referred (odds ratio [OR]: 0.99 [0.95-1.04]). Preemptively referred women (vs. men) were, on average, younger and with fewer comorbidities. There were no sex/gender differences in waitlisting once patients were preemptively referred (hazard ratio [HR]: 0.97 [0.91-1.03]); however, women (vs. men) who were preemptively referred remained 25% (HR: 0.75 [0.66-0.86]) less likely to receive a living donor transplant. Conclusion: In the Southeast US, men and women initiating KRT are similarly likely to be preemptively referred for a kidney transplant, and this appears, at least in part, to mitigate known sex/gender inequities in access to waitlisting, but not living donor transplant. Despite this, preemptively referred women, on average, had a more favorable medical profile relative to preemptively referred men.

Pay-for-Performance Incentives for Home Dialysis Use and Kidney Transplant.

Importance: The Centers for Medicare & Medicaid Services' mandatory End-Stage Renal Disease Treatment Choices (ETC) model, launched on January 1, 2021, randomly assigned approximately 30% of US dialysis facilities and managing clinicians to financial incentives to increase the use of home dialysis and kidney transplant. Objective: To assess the ETC's association with use of home dialysis and kidney transplant during the model's first 2 years and examine changes in these outcomes by race, ethnicity, and socioeconomic status. Design, Setting, and Participants: This retrospective cross-sectional study used claims and enrollment data for traditional Medicare beneficiaries with kidney failure from 2017 to 2022 linked to same-period transplant data from the United Network for Organ Sharing. The study data span 4 years (2017-2020) before the implementation of the ETC model on January 1, 2021, and 2 years (2021-2022) following the model's implementation. Exposure: Receiving dialysis treatment in a region randomly assigned to the ETC model. Main Outcomes and Measures: Primary outcomes were use of home dialysis and kidney transplant. A difference-in-differences (DiD) approach was used to estimate changes in outcomes among patients treated in regions randomly selected for ETC participation compared with concurrent changes among patients treated in control regions. Results: The study population included 724 406 persons with kidney failure (mean [IQR] age, 62.2 [53-72] years; 42.5% female). The proportion of patients receiving home dialysis increased from 12.1% to 14.3% in ETC regions and from 12.9% to 15.1% in control regions, yielding an adjusted DiD estimate of -0.2 percentage points (pp; 95% CI, -0.7 to 0.3 pp). Similar analysis for transplant yielded an adjusted DiD estimate of 0.02 pp (95% CI, -0.01 to 0.04 pp). When further stratified by sociodemographic measures, including age, sex, race and ethnicity, dual Medicare and Medicaid enrollment, and poverty quartile, there was not a statistically significant difference in home dialysis use across joint strata of characteristics and ETC participation. Conclusions and Relevance: In this cross-sectional study, the first 2 years of the ETC model were not associated with increased use of home dialysis or kidney transplant, nor changes in racial, ethnic, and socioeconomic disparities in these outcomes.

Real-World Risk of Severe Cytopenias in Multiple Myeloma Patients Sequentially Treated with Immunomodulatory Drugs.

INTRODUCTION: Most multiple myeloma (MM) patients experience cytopenias, likely driven by both disease and treatment-related factors. Immunomodulatory agents (IMiDs), which form the backbone of most anti-myeloma regimens, are known to cause higher grade cytopenias. In this context, the impact of sequential IMiD treatments on cytopenia risk is unknown. METHODS: We evaluated the cumulative risks of severe cytopenias following second line of therapy (LOT) initiation in 5,573 MM patients in the Flatiron Health database. Patients for whom both LOTs 1 and 2 contained IMiDs were considered "sequentially exposed"; those for whom neither contained IMiDs were "never exposed." RESULTS: For the neutropenia outcome, compared to the never exposed, the sequentially exposed had the highest 1-year risk (risk difference [RD] 12%), followed by those only recently exposed during LOT 2 (RD 8%), then by those with only past exposure during LOT 1 (RD 5%). A similar pattern was observed for leukopenia, but no meaningful differences were observed for anemia or thrombocytopenia. The associations between sequential exposure, versus never, with neutropenia and leukopenia were even stronger among those with a recent cytopenia history. CONCLUSION: Results suggest that sequential exposure to IMiDs is a risk factor for higher grade cytopenias. These findings have profound clinical implications in choosing newer LOTs with potential risks of cytopenia.

Kidney Transplantation Contraindications: Variation in Nephrologist Practice and Training Vintage.

Introduction: Health system leaders aim to increase access to kidney transplantation in part by encouraging nephrologists to refer more patients for transplant evaluation. Little is known about nephrologists' referral decisions and whether nephrologists with older training vintage weigh patient criteria differently (e.g., more restrictively). Methods: Using a novel, iteratively validated survey of US-based nephrologists, we examined how nephrologists assess adult patients' suitability for transplant, focusing on established, important criteria: 7 clinical (e.g., overweight) and 7 psychosocial (e.g., insurance). We quantified variation in nephrologist restrictiveness-proportion of criteria interpreted as absolute or partial contraindications versus minor or negligible concerns-and tested associations between restrictiveness and nephrologist age (proxy for training vintage) in logistic regression models, controlling for nephrologist-level and practice-level factors. Results: Of 144 nephrologists invited, 42 survey respondents (29% response rate) were 85% male and 54% non-Hispanic White, with mean age 52 years, and 67% spent ≥1 day/wk in outpatient dialysis facilities. Nephrologists interpreted patient criteria inconsistently; consistency was lower for psychosocial criteria (intraclass correlation coefficient: 0.28) than for clinical criteria (intraclass correlation coefficient: 0.43; P < 0.01). With each additional 10 years of age, nephrologists' odds of interpreting criteria restrictively (top tertile) doubled (adjusted odds ratio [aOR] 1.96; 95% confidence interval [CI]: 0.95-4.07), with marginal statistical significance. This relationship was significant when interpreting psychosocial criteria (aOR: 3.18; 95% CI: 1.16-8.71) but not when interpreting clinical criteria (aOR: 1.12; 95% CI: 0.52-2.38). Conclusion: Nephrologists interpret evaluation criteria variably when assessing patient suitability for transplant. Guideline-based educational interventions could influence nephrologists' referral decision-making differentially by age.

Influence of incomplete death information on cumulative risk estimates in US claims data.

Administrative claims databases often do not capture date or fact of death, so studies using these data may inappropriately treat death as a censoring event-equivalent to other withdrawal reasons-rather than a competing event. We examined 1-, 3-, and 5-year inverse-probability-of-treatment weighted cumulative risks of a composite cardiovascular outcome among 34 527 initiators of telmisartan (exposure) and ramipril (referent), who were aged ≥55 years, in Optum (United States) claims data from 2003 to 2020. Differences in cumulative risks of the cardiovascular endpoint due to censoring of death (cause-specific), as compared with treating death as a competing event (subdistribution), increased with greater follow-up time and older age, where event and mortality risks were higher. Among ramipril users, 5-year cause-specific and subdistribution cumulative risk estimates per 100, respectively, were 16.4 (95% CI, 15.3-17.5) and 16.2 (95% CI, 15.1-17.3) among ages 55-64 (difference = 0.2) and were 43.2 (95% CI, 41.3-45.2) and 39.7 (95% CI, 37.9-41.4) among ages ≥75 (difference = 3.6). Plasmode simulation results demonstrated the differences in cause-specific versus subdistribution cumulative risks to increase with increasing mortality rate. We suggest researchers consider the cohort's baseline mortality risk when deciding whether real-world data with incomplete death information can be used without concern. This article is part of a Special Collection on Pharmacoepidemiology.

Disparities in Access to Liver Transplant Referral and Evaluation among Patients with Hepatocellular Carcinoma in Georgia.

Liver transplantation offers the best survival for patients with early-stage hepatocellular carcinoma (HCC). Prior studies have demonstrated disparities in transplant access; none have examined the early steps of the transplant process. We identified determinants of access to transplant referral and evaluation among patients with HCC with a single tumor either within Milan or meeting downstaging criteria in Georgia.Population-based cancer registry data from 2010 to 2019 were linked to liver transplant centers in Georgia. Primary cohort: adult patients with HCC with a single tumor ≤8 cm in diameter, no extrahepatic involvement, and no vascular involvement. Secondary cohort: primary cohort plus patients with multiple tumors confined to one lobe. We estimated time to transplant referral, evaluation initiation, and evaluation completion, accounting for the competing risk of death. In sensitivity analyses, we also accounted for non-transplant cancer treatment.Among 1,379 patients with early-stage HCC in Georgia, 26% were referred to liver transplant. Private insurance and younger age were associated with increased likelihood of referral, while requiring downstaging was associated with lower likelihood of referral. Patients living in census tracts with ≥20% of residents in poverty were less likely to initiate evaluation among those referred [cause-specific hazard ratio (csHR): 0.62, 95% confidence interval (CI): 0.42-0.94]. Medicaid patients were less likely to complete the evaluation once initiated (csHR: 0.53, 95% CI: 0.32-0.89).Different sociodemographic factors were associated with each stage of the transplant process among patients with early-stage HCC in Georgia, emphasizing unique barriers to access and the need for targeted interventions at each step. SIGNIFICANCE: Among patients with early-stage HCC in Georgia, age and insurance type were associated with referral to liver transplant, race, and poverty with evaluation initiation, and insurance type with evaluation completion. Opportunities to improve transplant access include informing referring providers about insurance requirements, addressing barriers to evaluation initiation, and streamlining the evaluation process.

Characterizing Fit-for-Purpose Real-World Data: An Assessment of a Mother-Infant Linkage in the Japan Medical Data Center Claims Database.

Purpose: Observational postapproval safety studies are needed to inform medication safety during pregnancy. Real-world databases can be valuable for supporting such research, but fitness for regulatory purpose must first be vetted. Here, we demonstrate a fit-for-purpose assessment of the Japan Medical Data Center (JMDC) claims database for pregnancy safety regulatory decision-making. Patients and Methods: The Duke-Margolis framework considers a database's fitness for regulatory purpose based on relevancy (capacity to answer the research question based on variable availability and a sufficiently sized, representative population) and quality (ability to validly answer the research question based on data completeness and accuracy). To assess these considerations, we examined descriptive characteristics of infants and pregnancies among females ages 12-55 years in the JMDC between January 2005 and March 2022. Results: For relevancy, we determined that critical data fields (maternal medications, infant major congenital malformations, covariates) are available. Family identification codes permitted linkage of 385,295 total mother-infant pairs, 57% of which were continuously enrolled during pregnancy. The prevalence of specific congenital malformation subcategories and maternal medical conditions were representative of the general population, but preterm births were below expectations (3.6% versus 5.6%) in this population. For quality, our methods are expected to accurately identify the complete set of mothers and infants with a shared health insurance plan. However, validity of gestational age information was limited given the high proportion (60%) of missing live birth delivery codes coupled with suppression of infant birth dates and inaccessibility of disease codes with gestational week information. Conclusion: The JMDC may be well suited for descriptive studies of pregnant people in Japan (eg, comorbidities, medication usage). More work is needed to identify a method to assign pregnancy onset and delivery dates so that in utero medication exposure windows can be defined more precisely as needed for many regulatory postapproval pregnancy safety studies.

Implementation of the ASCENT Trial to Improve Transplant Waitlisting Access.

Introduction: The Allocation System for changes in Equity in Kidney Transplantation (ASCENT) study was a hybrid type 1 trial of a multicomponent intervention among 655 US dialysis facilities with low kidney transplant waitlisting to educate staff and patients about kidney allocation system (KAS) changes and increase access to and reduce racial disparities in waitlisting. Intervention components included a staff webinar, patient and staff educational videos, and facility-specific feedback reports. Methods: Implementation outcomes were assessed using the Reach, Effectiveness, Adoption, Implementation, and Maintenance Framework. Postimplementation surveys were administered among intervention group facilities (n = 334); interviews were conducted with facility staff (n = 6). High implementation was defined as using 3 to 4 intervention components, low implementation as using 1 to 2 components, and nonimplementation as using no components. Results: A total of 331 (99%) facilities completed the survey; 57% were high implementers, 31% were low implementers, and 12% were nonimplementers. Waitlisting events were higher or similar among high versus low implementer facilities for incident and prevalent populations; for Black incident patients, the mean proportion waitlisted in low implementer facilities was 0.80% (95% confidence interval [CI]: 0.73-0.87) at baseline and 0.55% at 1-year (95% CI: 0.48-0.62) versus 0.83% (95% CI: 0.78-0.88) at baseline and 1.40% at 1-year (95% CI: 1.35-1.45) in high implementer facilities. Interviews revealed that the intervention helped facilities prioritize transplant education, but that intervention components were not uniformly shared. Conclusion: The findings provide important context to interpret ASCENT effectiveness results and identified key barriers and facilitators to consider for future modification and scale-up of multilevel, multicomponent interventions in dialysis settings.

Social Risk and Dialysis Facility Performance in the First Year of the ESRD Treatment Choices Model.

Importance: The End-Stage Renal Disease Treatment Choices (ETC) model randomly selected 30% of US dialysis facilities to receive financial incentives based on their use of home dialysis, kidney transplant waitlisting, or transplant receipt. Facilities that disproportionately serve populations with high social risk have a lower use of home dialysis and kidney transplant raising concerns that these sites may fare poorly in the payment model. Objective: To examine first-year ETC model performance scores and financial penalties across dialysis facilities, stratified by their incident patients' social risk. Design, Setting, and Participants: A cross-sectional study of 2191 US dialysis facilities that participated in the ETC model from January 1 through December 31, 2021. Exposure: Composition of incident patient population, characterized by the proportion of patients who were non-Hispanic Black, Hispanic, living in a highly disadvantaged neighborhood, uninsured, or covered by Medicaid at dialysis initiation. A facility-level composite social risk score assessed whether each facility was in the highest quintile of having 0, 1, or at least 2 of these characteristics. Main Outcomes and Measures: Use of home dialysis, waitlisting, or transplant; model performance score; and financial penalization. Results: Using data from 125 984 incident patients (median age, 65 years [IQR, 54-74]; 41.8% female; 28.6% Black; 11.7% Hispanic), 1071 dialysis facilities (48.9%) had no social risk features, and 491 (22.4%) had 2 or more. In the first year of the ETC model, compared with those with no social risk features, dialysis facilities with 2 or more had lower mean performance scores (3.4 vs 3.6, P = .002) and lower use of home dialysis (14.1% vs 16.0%, P < .001). These facilities had higher receipt of financial penalties (18.5% vs 11.5%, P < .001), more frequently had the highest payment cut of 5% (2.4% vs 0.7%; P = .003), and were less likely to achieve the highest bonus of 4% (0% vs 2.7%; P < .001). Compared with all other facilities, those in the highest quintile of treating uninsured patients or those covered by Medicaid experienced more financial penalties (17.4% vs 12.9%, P = .01) as did those in the highest quintile in the proportion of patients who were Black (18.5% vs 12.6%, P = .001). Conclusions: In the first year of the Centers for Medicare & Medicaid Services' ETC model, dialysis facilities serving higher proportions of patients with social risk features had lower performance scores and experienced markedly higher receipt of financial penalties.

Factors Affecting Treatment Selection Among Patients With Hidradenitis Suppurativa.

Importance: Despite the US Food and Drug Administration's approval of adalimumab for the treatment of hidradenitis suppurativa (HS), prescription rates remain low, indicating a critical gap between evidence-based guidelines and clinical practice. Understanding the medical decision-making process that these patients use when considering biologic agents and other HS therapies may uncover opportunities for improved patient-physician communication and HS disease control. Objective: To elucidate factors that affect the medical decision-making process for patients with HS, with an emphasis on biologic therapies. Design, Setting, and Participants: Open-ended semistructured interviews were conducted with English-speaking adults with HS (aged ≥18 years) recruited from 2 dermatology clinics that are part of Emory University School of Medicine in Atlanta, Georgia. All participants had an average 7-day pain score of 1 or higher on a 0- to 10-point numeric rating scale. Surveys were conducted between November 2019 and March 2020, and data were analyzed from December 2021 to August 2022. Data collection continued until thematic saturation was reached at 21 interviews. Results: A total of 21 participants (median [IQR] age, 38.5 [27.9-43.4] years; 16 females [76%]) were included in the analysis. Almost all participants (96%) had Hurley stage II or III disease, and 15 (71%) had a history of adalimumab use. Suffering threshold, perceptions of treatment risk, treatment fatigue, disease understanding, and sources of information (included dermatologists, the internet, advertisements, and friends and loved ones) were identified as factors affecting participants' decisions to initiate new treatments for HS. Conclusions and Relevance: Results of this qualitative study suggest that mitigating misconceptions about treatment risk, identifying gaps in disease knowledge, and emphasizing early treatment to prevent scarring and disease progression may empower patients with HS to engage in treatment planning and to try new therapies.