Early Kidney Transplantation or Conversion to Peritoneal Dialysis after First-Time Arteriovenous Access Creation.

OBJECTIVES: After autogenous arteriovenous (AV) access creation for end-stage renal disease, a majority of patients will continue on hemodialysis (HD), a minority will receive definitive treatment with kidney transplantation, and a subset of patients will convert to peritoneal dialysis (PD). Our goal was to identify patient factors associated with early transition from HD to either kidney transplantation or PD. METHODS: This is a case-control study of all patients with first-time AV access creation in the Vascular Quality Initiative (2011-2022) who had long-term follow-up. Patients who remained on HD after AV access creation were the control group while patients who received early kidney transplant or who converted to PD were the two case groups. Relationship among demographics, comorbidities, neighborhood social disadvantage, and functional status as they relate to renal replacement therapy modality was assessed. RESULTS: There were 19,782 patients included; the average age was 62±15 years and 57% were male. During the follow-up period of a median 306 (71-403) days, 1.3% underwent a kidney transplantation and 2.3% underwent conversion to PD. On univariable analysis, rates of kidney transplantation or conversion to PD varied with race (P<.001), insurance status (P<.001), Area Deprivation Index (ADI) quintile (P<.001), and several medical comorbidities. On multivariable analysis, impaired ambulation, current smoking, Medicaid or Medicare insurance, Black race, heart failure, body mass index, and older age were associated with decreased transplantation rates. Conversion to PD was associated with ADI Q5, Q4, and Q3. Decreased conversion to PD was associated with impaired ambulation, Hispanic ethnicity, Black race, former smoking, medication-controlled diabetes, and older age. CONCLUSION: Decreased kidney transplantation was associated with Black race and non-commercial health insurance but not ADI quintile, suggesting disparities exist beyond community-level access to care. Early kidney transplantation conveyed a 3-year survival benefit compared to HD and PD, which had similar survival. Further work is required to increase access to kidney transplantation and PD.

Clinically relevant cut-points for changes in the Liver Frailty Index are associated with waitlist mortality in patients with cirrhosis.

BACKGROUND & AIMS: Physical frailty is a critical determinant of mortality in patients with cirrhosis and can be objectively measured using the Liver Frailty Index (LFI) that is potentially modifiable.. We aimed to LFI cut-points associated with waitlist mortality. APPROACH & RESULTS: Ambulatory adults with cirrhosis without HCC awaiting liver transplantation (LT) from 9 centers from 2012-2021 for ≥3 months with ≥2 pre-LT LFI assessments were included. The primary explanatory variable was change in LFI from first to second assessments per 3 months (∆LFI); we evaluated clinically-relevant ∆LFI cut-points at 0.1, 0.2, 0.3, and 0.5. The primary outcome was waitlist mortality (death or delisting for being too sick) with transplant considered as a competing event. Among 1029 patients, median (IQR) age was 58 (51-63) years; 42% were female; and median lab MELDNa at first assessment was 18 (15-22). For each 0.1 improvement in ∆LFI, risk of overall mortality decreased by 6% (cause-specific hazard ratio [cHR] 0.94, 95%CI 0.92-0.97, p < 0.001). ∆LFI was associated with waitlist mortality at cut-points as low as 0.1 (cHR 0.63, 95%CI 0.46-0.87) and 0.2 (HR 0.61, 95%CI 0.42-0.87). CONCLUSIONS: An improvement in LFI per 3 months as small as 0.1 in the pre-LT period is associated with a clinically meaningful reduction in waitlist mortality. These data provide estimates of the reduction in mortality risk associated with improvements in LFI that can be used to assess effectiveness of interventions targeting physical frailty in cirrhosis patients.

Medicare billing and utilization trends in vascular surgery.

OBJECTIVE: Within the past decade, Medicare Part B reimbursements for various surgical procedures have been declining, whereas health care expenses continue to increase. As a result, hospitals may increase service charges to offset losses in revenue, which may disproportionately affect underinsured patients. Our analysis aimed to characterize Medicare billing and utilization trends across common vascular surgical procedures. METHODS: The 2017 to 2021 Medicare Physician and Other Practitioners by Provider and Service dataset was queried for Current Procedural Terminology (CPT) codes for common vascular surgery procedures. The average charges, reimbursements, charge-to-reimbursement ratios, and service counts were calculated for the most common interventions performed by vascular surgeons. Data was stratified by care setting, facility (inpatient and outpatient hospital) vs non-facility locations. All monetary values were adjusted to the 2021 United States dollars to account for inflation. RESULTS: For facility settings, the mean charge billed to Medicare Part B increased from $3708 to $3952 (6.6%) from 2017 to 2021, with the average charge-to-reimbursement ratio increasing from 7.2 to 8.6. There were 17 of the 19 facility procedures that had a decline in reimbursements, decreasing from an average of $558 to $499 (-10.4%). Stab phlebectomy had the largest individual decrease in facility reimbursement (-53.5%), followed by above-knee amputation (-11.3%) and below-knee amputation (-11.0%). Both non-facility charges (-10.8%) and reimbursements (-12.2%) declined over the study period. Procedural utilization remained stable from 2017 to 2019. Tibial and femoral-popliteal atherectomy had increases of 45.9% and 33.7%, respectively, in overall procedural utilization when performed in non-facility settings from 2017 to 2019. CONCLUSIONS: Our analysis of vascular surgery procedures billed to Medicare Part B from 2017 to 2021 demonstrates an increase in charges, a decline in reimbursements, and a resultant increase in charge-to-reimbursement ratios for facility care settings. In contrast, non-facility charges have decreased in the face of declining reimbursements. These markups in submitted charges in facility locations may serve as an additional barrier to accessing care for patients who are underinsured.

Higher stroke risk after carotid endarterectomy and transcarotid artery revascularization is associated with relative surgeon volume ratio.

OBJECTIVE: Adoption of transcarotid artery revascularization (TCAR) by surgeons has been variable, with some still performing traditional carotid endarterectomy (CEA), whereas others have shifted to mostly TCAR. Our goal was to evaluate the association of relative surgeon volume of CEA to TCAR with perioperative outcomes. METHODS: The Vascular Quality Initiative CEA and carotid artery stent registries were analyzed from 2021 to 2023 for symptomatic and asymptomatic interventions. Surgeons participating in both registries were categorized in the following CEA to CEA+TCAR volume percentage ratios: 0.25 (majority TCAR), 0.26 to 0.50 (more TCAR), 0.51 to 0.75 (more CEA), and 0.76 to 1.00 (majority CEA). Primary outcomes were rates of perioperative ipsilateral stroke, death, cranial nerve injury, and return to the operating room for bleeding. RESULTS: There were 50,189 patients who underwent primary carotid revascularization (64.3% CEA and 35.7% TCAR). CEA patients were younger (71.1 vs 73.5 years, P < .001), with more symptomatic cases, less coronary artery disease, diabetes, and lower antiplatelet and statin use (all P < .001). TCAR patients had lower rates of smoking, obesity, and dialysis or renal transplant (all P < .001). Postoperative stroke after CEA was significantly impacted by the operator CEA to TCAR volume ratio (P = .04), with surgeons who perform majority TCAR and more TCAR having higher postoperative ipsilateral stroke (majority TCAR odds ratio [OR]: 2.15, 95% confidence interval [CI]: 1.16-3.96, P = .01; more TCAR OR: 1.42, 95% CI: 1.02-1.96, P = .04), as compared with those who perform majority CEA. Similarly, postoperative stroke after TCAR was significantly impacted by the CEA to TCAR volume ratio (P = .02), with surgeons who perform majority CEA and more CEA having higher stroke (majority CEA OR: 1.51, 95% CI: 1.00-2.27, P = .05; more CEA OR: 1.50, 95% CI: 1.14-2.00, P = .004), as compared with those who perform majority TCAR. There was no association between surgeon ratio and perioperative death, cranial nerve injury, and return to the operating room for bleeding for either procedure. CONCLUSIONS: The relative surgeon CEA to TCAR ratio is significantly associated with perioperative stroke rate. Surgeons who perform a majority of one procedure have a higher stroke rate in the other. Surgeons offering both operations should maintain a balanced practice and have a low threshold to collaborate as needed.

Scaling of soil organic carbon in space and time in the Southern Coastal Plain, USA.

Soil organic carbon (SOC) is a dynamic soil property (DSP) that represents the largest portion of terrestrial carbon. Its relevance to carbon sequestration and the potential effects of land use on SOC storage, make it imperative to map across both space and time. Most regional-scale studies mapping SOC give static estimates and train different models for different periods with varying accuracies. We developed a flexible modeling approach called DSP-Scale to map SOC in both space and time. DSP-Scale uses ecological concepts and empirical data to predict DSP dynamics using inherent soil properties (static factors) and land cover changes (dynamic factors). We compiled SOC data for the 0-20 cm depth (SOC20) from 1441 points spanning a 25 million ha study area in the southeastern U.S. Coastal Plain, incorporating data from the Rapid Carbon Assessment, National Cooperative Soil Survey Soil Characterization database, and other regional studies. We developed a random forest model using climate, topography, soil survey, and land cover changes to predict SOC20 dynamics for five-year periods between 2001 and 2019. Our model explained 66 % and 59 % of the variation for the training and test data, respectively. Top predictors included mean annual precipitation, slope, and soil erosion class. Land cover 10 years before measurements of SOC20 was more important than current land cover for estimating SOC20. We estimated total SOC stocks of 207.1 and 208.3 Tg for 2001 and 2019, respectively. Highest gains of total SOC stock (0.9 Tg from 2001 to 2019) were associated with land cover change from mixed to evergreen forest. The greatest loss of total SOC stock (0.2 Tg) in the same period was associated with land cover change from pasture/hay to evergreen forest. We concluded that the DSP-Scale approach provides a flexible way to use dynamic and static factors affecting SOC stocks to predict changes in space and time at regional scales.

Galactokinase-like protein from Leishmania donovani: Biochemical and structural characterization of a recombinant protein.

Leishmaniasis is a spectrum of conditions caused by infection with the protozoan Leishmania spp. parasites. Leishmaniasis is endemic in 98 countries around the world, and resistance to current anti-leishmanial drugs is rising. Our work has identified and characterised a previously unstudied galactokinase-like protein (GalK) in Leishmania donovani, which catalyses the MgATP-dependent phosphorylation of the C-1 hydroxyl group of d-galactose to galactose-1-phosphate. Here, we report the production of the catalytically active recombinant protein in E. coli, determination of its substrate specificity and kinetic constants, as well as analysis of its molecular envelope using in solution X-ray scattering. Our results reveal kinetic parameters in range with other galactokinases with an average apparent Km value of 76 µM for galactose, Vmax and apparent Kcat values with 4.46376 × 10-9 M/s and 0.021 s-1, respectively. Substantial substrate promiscuity was observed, with galactose being the preferred substrate, followed by mannose, fructose and GalNAc. LdGalK has a highly flexible protein structure suggestive of multiple conformational states in solution, which may be the key to its substrate promiscuity. Our data presents novel insights into the galactose salvaging pathway in Leishmania and positions this protein as a potential target for the development of pharmaceuticals seeking to interfere with parasite substrate metabolism.

Alternative Conduits for Lower Extremity Bypass.

While single-segment great saphenous vein (GSV) remains the gold-standard conduit for infrainguinal bypass, several alternative options are available for use when GSV is absent in patients with chronic limb threatening ischemia requiring infrainguinal revascularization including alternative autologous vein, prosthetic conduits, and cryopreserved vein grafts.

Liver transplant for primary biliary tract neuroendocrine tumor in a nine-year-old girl.

BACKGROUND: Neuroendocrine tumors (NETs) are rare epithelial neoplasms that arise most commonly from the gastrointestinal tract. In pediatrics, the most common site of origin is in the appendix, with the liver being the most common site of metastasis. Neuroendocrine tumors arising from the biliary tract are extremely rare. METHODS: We describe a case of a nine-year-old girl who presented with obstructive cholestasis and was found to have multiple liver masses identified on biopsy as well-differentiated neuroendocrine tumor with an unknown primary tumor site. RESULT: The patient underwent extensive investigation to identify a primary tumor site, including endoscopy, endoscopic ultrasound, and capsule endoscopy. The patient ultimately underwent definitive management with liver transplant, and on explant was discovered to have multiple well-differentiated neuroendocrine tumors, WHO Grade 1, with extensive infiltration into the submucosa of bile duct, consistent with primary biliary tract neuroendocrine tumor. CONCLUSION: Identifying the site of the primary tumor in NETs found within the liver can be challenging. To determine if an extrahepatic primary tumor exists, workup should include endoscopy, EUS, and capsule endoscopy. Children with well-differentiated hepatic NETs, with no identifiable primary tumor, and an unresectable tumor, are considered favorable candidates for liver transplantation.

Naturally segregating genetic variants contribute to thermal tolerance in a Drosophila melanogaster model system.

Thermal tolerance is a fundamental physiological complex trait for survival in many species. For example, everyday tasks such as foraging, finding a mate, and avoiding predation are highly dependent on how well an organism can tolerate extreme temperatures. Understanding the general architecture of the natural variants within the genes that control this trait is of high importance if we want to better comprehend thermal physiology. Here, we take a multipronged approach to further dissect the genetic architecture that controls thermal tolerance in natural populations using the Drosophila Synthetic Population Resource as a model system. First, we used quantitative genetics and Quantitative Trait Loci mapping to identify major effect regions within the genome that influences thermal tolerance, then integrated RNA-sequencing to identify differences in gene expression, and lastly, we used the RNAi system to (1) alter tissue-specific gene expression and (2) functionally validate our findings. This powerful integration of approaches not only allows for the identification of the genetic basis of thermal tolerance but also the physiology of thermal tolerance in a natural population, which ultimately elucidates thermal tolerance through a fitness-associated lens.

Outcomes following concomitant multiorgan heart transplantation from circulatory death donors: The United States experience.

BACKGROUND: Donation after circulatory death (DCD) has reemerged as a method of expanding the donor heart pool. Given the high waitlist mortality of multiorgan heart candidates, we evaluated waitlist outcomes associated with willingness to consider DCD offers and post-transplant outcomes following DCD transplant for these candidates. METHODS: We identified adult multiorgan heart candidates and recipients between January 1, 2020 and March 31, 2023 nationally. Among candidates that met inclusion criteria, we compared the cumulative incidence of transplant, with waitlist death/deterioration as a competing risk, by willingness to consider DCD offers. Among recipients of DCD versus brain death (DBD) transplants, we compared perioperative outcomes and post-transplant survival. RESULTS: Of 1,802 heart-kidney, 266 heart-liver, and 440 heart-lung candidates, 15.8%, 12.4%, and 31.1%, respectively, were willing to consider DCD offers. On adjusted analysis, willingness to consider DCD offers was associated with higher likelihood of transplant for all multiorgan heart candidates and decreased likelihood of waitlist deterioration for heart-lung candidates. Of 1,100 heart-kidney, 173 heart-liver, and 159 heart-lung recipients, 5.4%, 2.3%, and 2.5%, respectively, received DCD organs. Recipients of DCD and DBD heart-kidney transplants had a similar likelihood of perioperative outcomes and 1-year survival. All other DCD multiorgan heart recipients have survived to the last follow-up. CONCLUSIONS: Multiorgan heart candidates who were willing to consider DCD offers had favorable waitlist outcomes, and heart-kidney recipients of DCD transplants had similar post-transplant outcomes to recipients of DBD transplants. We recommend the use of DCD organs to increase the donor pool for these high-risk candidates.

Agave distribution and floral display influence foraging rates of an endangered pollinating bat and implications for conservation.

Wildlife conservation involves making management decisions with incomplete knowledge of ecological relationships. Efforts to augment foraging resources for the endangered Mexican long-nosed bat (Leptonycteris nivalis) are progressing despite limited knowledge about the species' foraging behavior and requirements. This study aimed to understand L. nivalis responses to floral resource availability, focusing on individual agave- and local-scale characteristics influencing visitation rates to flowering agaves. We observed bat visitation at 62 flowering agaves around two roosts in northeast Mexico on 46 nights in the summers of 2017 and 2018. We found visitation rate had positive relationships with two agave-scale characteristics: the number of umbels with open flowers and the lower vertical position on the stalk of those umbels (i.e., earlier phenological stages of flowering). However, these factors exhibited strong negative interaction: with few umbels with open flowers, the position of flowering umbels had little effect on visitation rate, but when umbels with open flowers were abundant, visitation rate was more strongly related to the lower flowering umbel position. We also found relationships between visitation rate and two local-scale characteristics: negative for the density of flowering conspecifics within 30 m of the focal agave and positive for the density of dead standing agave stalks within 30 m. Our findings suggest opportunities to augment foraging resources for L. nivalis in ways that are consistent with their foraging behavior, including: increasing the supply of simultaneously blooming flowers by planting agave species that tend to have more umbels with simultaneously open flowers; planting multiple species of agaves with different flowering times to increase the availability of agaves with open flowers on lower-positioned umbels throughout the period when bats are present in the region; planting agaves in clusters; and keeping dead standing agave stalks on the landscape. Our study points to useful management strategies that can be implemented and monitored as part of an adaptive management approach to aid in conservation efforts.

HIV stigma and other barriers to COVID-19 vaccine uptake among Georgian people living with HIV/AIDS: A mixed-methods study.

We conducted a study in Georgia to examine behavioral insights and barriers to COVID-19 vaccine uptake among people living with HIV (PLWH). Between December 2021-July 2022, we collected quantitative data to evaluate participants' demographics, COVID-19 knowledge, attitude, perception, and HIV stigma as potential covariates for being vaccinated against COVID-19. We conducted a multivariate analysis to define the factors independently associated with COVID-19 vaccination among PLWH. We collected qualitative data to explore individual experiences of their positive or negative choices, main barriers, HIV stigma, and preferences for receiving vaccination. Of the total 85 participants of the study, 52.9% were vaccinated; 61.2% had concerns with the disclosure of HIV status at the vaccination site. Those who believed they would have a severe form of COVID-19 were more likely to be vaccinated (OR = 23.8; 95% CI: 5.1-111.7). The association stayed significant after adjusting for sex, age, education level, living area, health care providers' unfriendly attitudes, and their fear of disclosing HIV status at vaccination places. Based on the qualitative study, status disclosure was a significant barrier to receiving care; therefore, PLWH prefer to receive COVID-19 vaccination integrated in HIV services. Conclusions: In this study, around half of the participants were not vaccinated against COVID-19. The main reasons for not being vaccinated included stigma, misleading health beliefs, and low awareness about COVID-19. An integrated service delivery model may improve vaccination uptake among PLWH in Georgia.

Dissemination of the Women-Centred HIV Care Model: A Multimodal Process and Evaluation.

BACKGROUND: Using data from a national cohort study and focus groups, the Women-Centred HIV Care (WCHC) Model was developed to inform care delivery for women living with HIV. METHODS: Through an evidence-based, integrated knowledge translation approach, we developed 2 toolkits based on the WCHC Model for service providers and women living with HIV in English and French (Canada's national languages). To disseminate, we distributed printed advertising materials, hosted 3 national webinars and conducted 2 virtual capacity-building training series. RESULTS: A total of 315 individuals attended the webinars, and the average WCHC knowledge increased by 29% (SD 4.3%). In total, 131 service providers engaged in 22 virtual capacity-building training sessions with 21 clinical cases discussed. Learners self-reported increased confidence in 15/15 abilities, including the ability to provide WCHC. As of December 2023, the toolkits were downloaded 7766 times. CONCLUSIONS: We successfully developed WCHC toolkits and shared them with diverse clinical and community audiences through various dissemination methods.

A study on creating and sharing a toolkit for healthcare providers and women living with HIVWhy was the study done?:The research team created the Women-Centred HIV Care (WCHC) model to help healthcare providers deliver personalised and thorough care to women living with HIV in Canada. This study aimed to develop a practical toolkit based on the model. The goal was to share this toolkit with women and their providers in various ways to get feedback on its usefulness and to understand the best methods for sharing tools in the future.What did the researchers do?:Through an in-depth, collaborative process, English and French WCHC toolkits were developed by a large and diverse team of women and providers. Various methods including printed materials, national webinars and virtual trainings were used to share the toolkits across Canada. The team assessed the toolkit's reception by using surveys, focus groups and tracking toolkit downloads and webpage views.What did the researchers find?:The study found positive results, including a 29% increase in WCHC knowledge for 315 webinar participants and enhanced confidence in 15 abilities for 131 service providers during virtual training. The toolkits were downloaded 7766 times, indicating broad interest. Usability testing showed that the toolkits were easy to use and helpful. Attendees of the webinars and virtual trainings indicated they were likely to use the toolkit and recommend it to others.What do the findings mean?:Overall, the WCHC toolkits offer valuable guidance to women living with HIV and their providers. The study improved providers' knowledge and confidence in delivering WCHC, especially during the virtual training sessions that focused on applying this knowledge to real clinical cases. During months when the toolkit was shared through printed materials, webinars and virtual training, more people visited the toolkit webpage. The study highlighted the importance of involving those who will use healthcare tools from the beginning and using many ways to share these tools to reach more people.

Assessing Time to Removal of Tunneled Dialysis Catheters after Arteriovenous Access Creation.

BACKGROUND: Tunneled dialysis catheters (TDCs) are a temporary bridge until definitive arteriovenous (AV) access is established. Our objective was to evaluate the time to TDC removal in patients who underwent AV access creations with TDCs already in place. METHODS: A single-center analysis of all AV access creations in patients with TDCs was performed (2014-2020). Primary outcome was time to TDC removal after access creation. RESULTS: There were 364 AV access creations with TDCs in place. The average age was 58 years, 44% of patients were female, and 64% were Black. The median time to TDC removal was 113 days (range, 22-931 days) with 71.4% having a TDC >90 days after access creation. Patients with TDC >90 days were often older (60 vs. 54.7), had hypertension (98.1% vs. 93.3%), were diabetic (65.4% vs. 47.1%), and had longer average time to maturation (107.1 vs. 55.4 days, P < 0.001) and first access (114 vs. 59.4 days, P < 0.001). Multivariable analysis showed that older age was associated with prolonged TDC placement (odds ratio [OR] 1.03, 95% confidence interval [CI] 1.01-1.05, P = 0.005) and prosthetic graft use was associated with shorter TDC indwelling time (OR 0.09, 95% CI 0.04-0.23, P ≤ 0.001). Kaplan-Meier analysis showed that 87% of TDCs were removed at 1 year. CONCLUSIONS: The majority of patients with TDCs who underwent AV access creation had prolonged TDC placement. Prosthetic graft use was associated with shorter catheter times. Close follow-up after access placement, improving maturation times, and access type selection should be considered to shortened TDC times.

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.

Characterization of long-term survival in Medicare patients undergoing arteriovenous hemodialysis access.

BACKGROUND: Patients undergoing arteriovenous (AV) access creation for hemodialysis often have significant comorbidities. Our goal was to quantify the long-term survival and associated risks factors for long-term mortality in these patients to aid in optimization of goals and expectations. METHODS: The Vascular Implant Surveillance and Interventional Outcomes Network Vascular Quality Initiative Medicare linked data was used to assess long-term survival in the HD registry. Demographics, comorbidities, and interventions were recorded. Because the majority of hemodialysis patients are provided Medicare, Medicare linkage was used to obtain survival data. Multivariable analysis was used to identify independent associations with mortality. RESULTS: There were 13,945 AV access patients analyzed including 10,872 (78%) AV fistulas and 3073 (22%) AV grafts. The median age was 67 years and 56% of patients were male. Approximately one-third had a prior AV access and 44.7% had prior tunneled dialysis catheters. Patients receiving an AV fistula, compared with AV grafts, were more often younger, male, White, obese, independently ambulatory, preoperatively living at home, and less often have a prior AV access and tunneled dialysis catheters (P < .05 for all). The 5-year mortality overall was 62.9% with 61.2% for AV fistulas and 68.8% for AV grafts (P < .001). On multivariable analysis for 5 year mortality, nonambulatory status (hazard ratio [HR], 1.67; 95% confidence interval [CI], 1.53-1.83; P < .001), lower extremity access (HR, 1.67; 95% CI, 1.35-2.05; P < .001), human immunodeficiency virus or acquired immunodeficiency syndrome (HR, 1.44; 95% CI, 1.13-1.82; P < .001), White race (HR, 1.43; 95% CI, 1.35-1.51; P < .001), congestive heart failure (HR, 1.33; 95% CI, 1.26-1.41; P < .001), chronic obstructive pulmonary disease (HR, 1.23; 95% CI, 1.15-1.31; P < .001), and AV graft placement (HR, 1.12; 95% CI, 1.02-1.23, P = .016) were most associated with poor survival. Factors associated with improved survival were never smoking (HR, .73; 95% CI, 0.67-0.79; P < .001), prior/quit smoking (HR, .78; 95% CI, 0.72-0.84; P < .001), preoperative home living (HR, .75; 95% CI, 0.68-0.83; P < .001), and hypertension (HR, .89; 95% CI, 0.8-0.99; P = .03). CONCLUSIONS: Long-term survival in Medicare patients undergoing AV access creation is poor with nearly two-thirds of patients having died at 5 years. There are many modifiable risk factors that may improve survival in these patients and give an opportunity for transplantation.

Impact of recipient age on mortality among Cytomegalovirus (CMV)-seronegative lung transplant recipients with CMV-seropositive donors.

BACKGROUND: Cytomegalovirus (CMV)-seronegative lung transplant recipients (LTRs) with seropositive donors (CMV D+/R-) have the highest mortality of all CMV serostatuses. Due to immunosenescence and other factors, we hypothesized CMV D+/R- status might disproportionately impact older LTRs. Thus, we investigated whether recipient age modified the relationship between donor CMV status and mortality among CMV-seronegative LTRs. METHODS: Adult, CMV-seronegative first-time lung-only recipients were identified through the Scientific Registry of Transplant Recipients between May 2005 and December 2019. We used adjusted multivariable Cox regression to assess the relationship of donor CMV status and death. Interaction between recipient age and donor CMV was assessed via likelihood ratio testing of nested Cox models and by the relative excess risk due to interaction (RERI) and attributable proportion (AP) of joint effects. RESULTS: We identified 11,136 CMV-seronegative LTRs. The median age was 59 years; 65.2% were male, with leading transplant indication of idiopathic pulmonary fibrosis (35.6%); and 60.8% were CMV D+/R-. In multivariable modeling, CMV D+/R- status was associated with 27% increased hazard of death (adjusted hazard ratio: 1.27, 95% confidence interval: 1.21-1.34) compared to CMV D-/R-. Recipient age ≥60 years significantly modified the relationship between donor CMV-seropositive status and mortality on the additive scale, including RERI 0.24 and AP 11.4% (p = 0.001), that is, the interaction increased hazard of death by 0.24 and explained 11.4% of mortality in older CMV D+ recipients. CONCLUSIONS: Among CMV-seronegative LTRs, donor CMV-seropositive status confers higher risk of posttransplant mortality, which is amplified in older recipients. Future studies should define optimal strategies for CMV prevention and management in older D+/R- LTRs.