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1.
PLoS One ; 15(3): e0230358, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32208424

RESUMO

Endothelial dysfunction is a critical event in vascular inflammation characterized, in part, by elevated surface expression of adhesion molecules such as intercellular adhesion molecule-1 (ICAM-1). ICAM-1 is heavily N-glycosylated, and like other surface proteins, it is largely presumed that fully processed, complex N-glycoforms are dominant. However, our recent studies suggest that hypoglycosylated or high mannose (HM)-ICAM-1 N-glycoforms are also expressed on the cell surface during endothelial dysfunction, and have higher affinity for monocyte adhesion and regulate outside-in endothelial signaling by different mechanisms. Whether different ICAM-1 N-glycoforms are expressed in vivo during disease is unknown. In this study, using the proximity ligation assay, we assessed the relative formation of high mannose, hybrid and complex α-2,6-sialyated N-glycoforms of ICAM-1 in human and mouse models of atherosclerosis, as well as in arteriovenous fistulas (AVF) of patients on hemodialysis. Our data demonstrates that ICAM-1 harboring HM or hybrid epitopes as well as ICAM-1 bearing α-2,6-sialylated epitopes are present in human and mouse atherosclerotic lesions. Further, HM-ICAM-1 positively associated with increased macrophage burden in lesions as assessed by CD68 staining, whereas α-2,6-sialylated ICAM-1 did not. Finally, both HM and α-2,6-sialylated ICAM-1 N-glycoforms were present in hemodialysis patients who had AVF maturation failure compared to successful AVF maturation. Collectively, these data provide evidence that HM- ICAM-1 N-glycoforms are present in vivo, and at levels similar to complex α-2,6-sialylated ICAM-1 underscoring the need to better understand their roles in modulating vascular inflammation.

2.
Am J Nephrol ; 51(2): 147-159, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31838480

RESUMO

BACKGROUND: Nephrology research is expanding, and harnessing the much-needed information and data for the practice of evidence-based medicine is becoming more challenging. In this study, we used the natural language processing and text mining approach to mitigate some of these challenges. METHODS: We analyzed 17,412 abstracts from the top-10 nephrology journals over 10 years (2007-2017) by using latent semantic analysis and topic analysis. RESULTS: The analyses revealed 10 distinct topics (T) for nephrology research ranging from basic science studies, using animal modeling (T-1), to dialysis vascular access-related issues -(T-10). The trend analyses indicated that while the majority of topics stayed relatively stable, some of the research topics experienced increasing popularity over time such as studies focusing on mortality and survival (T-4) and Patient-related Outcomes and Perspectives of Clinicians (T-5). However, some research topics such as studies focusing on animal modeling (T-1), predictors of acute kidney injury, and dialysis access (T-10) exhibited a downward trend. CONCLUSION: Stakeholders of nephrology research may use these trends further to develop priorities and enrich the research agenda for the future.

3.
J Am Soc Nephrol ; 30(11): 2209-2218, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31611240

RESUMO

BACKGROUND: About half of arteriovenous fistulas (AVFs) require one or more interventions before successful dialysis use, a process called assisted maturation. Previous research suggested that AVF abandonment and interventions to maintain patency after maturation may be more frequent with assisted maturation versus unassisted maturation. METHODS: Using the US Renal Data System, we retrospectively compared patients with assisted versus unassisted AVF maturation for postmaturation AVF outcomes, including functional primary patency loss (requiring intervention after achieving AVF maturation), AVF abandonment, and frequency of interventions. RESULTS: We included 7301 patients ≥67 years who initiated hemodialysis from July 2010 to June 2012 with a catheter and no prior AVF; all had an AVF created within 6 months of starting hemodialysis and used for dialysis (matured) within 6 months of creation, with 2-year postmaturation follow-up. AVFs matured without prior intervention for 56% of the patients. Assisted AVF maturation with one, two, three, or four or more prematuration interventions occurred in 23%, 12%, 5%, and 4% of patients, respectively. Patients with prematuration interventions had significantly increased risk of functional primary patency loss compared with patients who had unassisted AVF maturation, and the risk increased with the number of interventions. Although the likelihood of AVF abandonment was not higher among patients with up to three prematuration interventions compared with patients with unassisted AVF maturation, it was significantly higher among those with four or more interventions. CONCLUSIONS: For this cohort of patients undergoing assisted AVF maturation, we observed a positive association between the number of prematuration AVF interventions and the likelihood of functional primary patency loss and frequency of postmaturation interventions.

4.
Sci Rep ; 9(1): 15555, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31645573

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

5.
Am J Nephrol ; 50(3): 221-227, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31394548

RESUMO

BACKGROUND: Patients with advanced chronic kidney disease frequently undergo arteriovenous fistula creation prior to reaching end-stage renal disease (ESRD), but some initiate hemodialysis with a central vein catheter, if their fistula is not yet usable. The clinical consequences of the delay in fistula use have not been quantified in such patients. We compared patients with pre-ESRD fistula surgery who initiated dialysis with a catheter versus a fistula in terms of the frequency of post-dialysis vascular access procedures and complications and their economic impact. METHODS: We identified 205 patients with predialysis fistula creation from 2006 to 2012 at a large dialysis center who started hemodialysis within the ensuing 2 years. Of these, 91 (44%) initiated dialysis with a catheter and 114 (56%) with a fistula. We compared these 2 groups in terms of their annual frequency of percutaneous vascular access procedures, surgical access procedures, total access procedures, hospitalizations due to catheter-related bacteremia, and overall cost of vascular access management. RESULTS: The 2 groups were similar in demographics, comorbidities, and fistula type. As compared to patients initiating dialysis with a fistula, those initiating with a catheter had a significantly greater annual frequency of percutaneous access procedures (1.29 [1.19-1.40] vs. 0.75 [0.68-0.82]), surgical access procedures (0.69 [0.61-0.76] vs. 0.59 [0.53-0.66]), total access procedures (1.98 [1.86-2.11] vs. 1.34 [1.26-1.44]), and hospitalizations due to catheter-related bacteremia (0.09 [0.07-0.12] vs. 0.02 [0.01-0.03]). Patients initiating dialysis with a catheter incurred a median overall annual cost of access management that was USD 2,669 higher (USD 6,372 [3,121-12,242) vs. USD 3,703 [1,867-6,953], p = 0.0001). CONCLUSION: Among patients with predialysis fistula creation, those initiating dialysis with a catheter versus a fistula had substantially more frequent percutaneous, surgical, and total vascular access procedures, as well as hospitalizations due to catheter-related bacteremia. The annual cost of access management was substantially higher in those initiating dialysis with a catheter.

6.
Artigo em Inglês | MEDLINE | ID: mdl-31369099

RESUMO

BACKGROUND: Vascular access outcomes reported across haemodialysis (HD) trials are numerous, heterogeneous and not always relevant to patients and clinicians. This study aimed to identify critically important vascular access outcomes. METHOD: Outcomes derived from a systematic review, multi-disciplinary expert panel and patient input were included in a multilanguage online survey. Participants rated the absolute importance of outcomes using a 9-point Likert scale (7-9 being critically important). The relative importance was determined by a best-worst scale using multinomial logistic regression. Open text responses were analysed thematically. RESULTS: The survey was completed by 873 participants [224 (26%) patients/caregivers and 649 (74%) health professionals] from 58 countries. Vascular access function was considered the most important outcome (mean score 7.8 for patients and caregivers/8.5 for health professionals, with 85%/95% rating it critically important, and top ranked on best-worst scale), followed by infection (mean 7.4/8.2, 79%/92% rating it critically important, second rank on best-worst scale). Health professionals rated all outcomes of equal or higher importance than patients/caregivers, except for aneurysms. We identified six themes: necessity for HD, applicability across vascular access types, frequency and severity of debilitation, minimizing the risk of hospitalization and death, optimizing technical competence and adherence to best practice and direct impact on appearance and lifestyle. CONCLUSIONS: Vascular access function was the most critically important outcome among patients/caregivers and health professionals. Consistent reporting of this outcome across trials in HD will strengthen their value in supporting vascular access practice and shared decision making in patients requiring HD.

8.
Sci Rep ; 9(1): 4299, 2019 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-30862797

RESUMO

Creation of a hemodialysis arteriovenous fistula (AVF) causes aberrant vascular mechanics at and near the AVF anastomosis. When inadequately regulated, these aberrant mechanical factors may impede AVF lumen expansion to cause AVF maturation failure, a significant clinical problem with no effective treatments. The endothelial nitric oxide synthase (NOS3) system is crucial for vascular health and function, but its effect on AVF maturation has not been fully characterized. We hypothesize that NOS3 promotes AVF maturation by regulating local vascular mechanics following AVF creation. Here we report the first MRI-based fluid-structure interaction (FSI) study in a murine AVF model using three mouse strains: NOS3 overexpression (NOS3 OE) and knockout (NOS3-/-) on C57BL/6 background, with C57BL/6 as the wild-type control (NOS3+/+). When compared to NOS3+/+ and NOS3-/-, AVFs in the OE mice had larger lumen area. AVFs in the OE mice also had smoother blood flow streamlines, as well as lower blood shear stress at the wall, blood vorticity, inner wall circumferential stretch, and radial wall thinning at the anastomosis. Our results demonstrate that overexpression of NOS3 resulted in distinct hemodynamic and wall mechanical profiles associated with favorable AVF remodeling. Enhancing NOS3 expression may be a potential therapeutic approach for promoting AVF maturation.

9.
Am J Physiol Renal Physiol ; 316(5): F794-F806, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30785348

RESUMO

Vascular access is the lifeline for patients on hemodialysis. Arteriovenous fistulas (AVFs) are the preferred vascular access, but AVF maturation failure remains a significant clinical problem. Currently, there are no effective therapies available to prevent or treat AVF maturation failure. AVF maturation failure frequently results from venous stenosis at the AVF anastomosis, which is secondary to poor outward vascular remodeling and excessive venous intimal hyperplasia that narrows the AVF lumen. Arteriovenous grafts (AVGs) are the next preferred vascular access when an AVF creation is not possible. AVG failure is primarily the result of venous stenosis at the vein-graft anastomosis, which originates from intimal hyperplasia development. Although there has been advancement in our knowledge of the pathophysiology of AVF maturation and AVG failure, this has not translated into effective therapies for these two important clinical problems. Further work will be required to dissect out the mechanisms of AVF maturation failure and AVG failure to develop more specific therapies. This review highlights the major recent advancements in AVF and AVG biology, reviews major clinical trials, and discusses new areas for future research.


Assuntos
Derivação Arteriovenosa Cirúrgica/instrumentação , Implante de Prótese Vascular/instrumentação , Prótese Vascular , Oclusão de Enxerto Vascular/etiologia , Falha de Prótese , Diálise Renal , Animais , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Implante de Prótese Vascular/efeitos adversos , Oclusão de Enxerto Vascular/patologia , Oclusão de Enxerto Vascular/fisiopatologia , Oclusão de Enxerto Vascular/terapia , Humanos , Desenho de Prótese , Fatores de Risco , Estresse Mecânico , Falha de Tratamento , Grau de Desobstrução Vascular , Remodelação Vascular
10.
J Vasc Surg ; 69(2): 507-515, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30683197

RESUMO

OBJECTIVE: Arteriovenous fistulas created in patients with chronic kidney disease often lose patency and fail to become usable. This prospective trial evaluated the efficacy of vonapanitase, a recombinant human elastase, in promoting radiocephalic fistula patency and use for hemodialysis. METHODS: PATENCY-1 was a double-blind, placebo-controlled trial that enrolled 349 patients on or approaching hemodialysis and being evaluated for radiocephalic arteriovenous fistula creation. Of these, 313 were randomized and 311 treated. Patients were assigned to vonapanitase (n = 210) or placebo (n = 103). The study drug solution was applied topically to the artery and vein for 10 minutes immediately after fistula creation. The primary and secondary end points were primary patency (time to first thrombosis or corrective procedure) and secondary patency (time to abandonment). Tertiary end points included use of the fistula for hemodialysis, fistula maturation by ultrasound, and procedure rates. RESULTS: The Kaplan-Meier estimates of 12-month primary patency were 42% (95% confidence interval [CI], 35-49) and 31% (95% CI, 21-42) for vonapanitase and placebo (P = .25). The Kaplan-Meier estimates of 12-month secondary patency were 74% (95% CI, 68-80) and 61% (95% CI, 51-71) for vonapanitase and placebo (P = .048). The proportions of vonapanitase and placebo patients were 39% and 25% (P = .035) with unassisted use for hemodialysis and 64% and 44% (P = .006) with unassisted plus assisted use. CONCLUSIONS: Vonapanitase treatment did not significantly improve primary patency but was associated with increased secondary patency and use for hemodialysis. Further research is needed to evaluate these end points.


Assuntos
Derivação Arteriovenosa Cirúrgica , Proteínas de Transporte/administração & dosagem , Oclusão de Enxerto Vascular/prevenção & controle , Elastase Pancreática/administração & dosagem , Artéria Radial/cirurgia , Diálise Renal , Trombose/prevenção & controle , Extremidade Superior/irrigação sanguínea , Grau de Desobstrução Vascular/efeitos dos fármacos , Veias/cirurgia , Administração Tópica , Adulto , Idoso , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Proteínas de Transporte/efeitos adversos , Método Duplo-Cego , Feminino , Oclusão de Enxerto Vascular/etiologia , Oclusão de Enxerto Vascular/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Elastase Pancreática/efeitos adversos , Estudos Prospectivos , Artéria Radial/diagnóstico por imagem , Artéria Radial/fisiopatologia , Trombose/etiologia , Trombose/fisiopatologia , Fatores de Tempo , Resultado do Tratamento , Estados Unidos , Veias/diagnóstico por imagem , Veias/fisiopatologia
11.
Am J Nephrol ; 49(1): 11-19, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30544112

RESUMO

BACKGROUND: Despite national vascular access guidelines promoting the use of arteriovenous fistulas (AVF) over arteriovenous grafts (AVGs) for dialysis, AVF use is substantially lower in females. We assessed clinically relevant AVF and AVG surgical outcomes in elderly male and female patients initiating hemodialysis with a central venous catheter (CVC). METHODS: Using the United States Renal Data System standard analytic files linked with Medicare claims, we assessed incident hemodialysis patients in the United States, 9,458 elderly patients (≥67 years; 4,927 males and 4,531 females) initiating hemodialysis from July 2010 to June 2011 with a catheter and had an AVF or AVG placed within 6 months. We evaluated vascular access placement, successful use for dialysis, assisted use (requiring an intervention before successful use), abandonment after successful use, and rate of interventions after successful use. RESULTS: Females were less likely than males to receive an AVF (adjusted likelihood 0.57, 95% CI 0.52-0.63). Among patients receiving an AVF, females had higher adjusted likelihoods of unsuccessful AVF use (hazard ratio [HR] 1.46, 95% CI 1.36-1.56), assisted AVF use (OR 1.34, 95% CI 1.17-1.54), and AVF abandonment (HR 1.28, 95% CI 1.10-1.50), but similar relative rate of AVF interventions after successful use (relative risk [RR] 1.01, 95% CI 0.94-1.08). Among patients receiving an AVG, females had a lower likelihood of unsuccessful AVG use (HR 0.83, 95% CI 0.73-0.94), similar rates of assisted AVG use (OR 1.05, 95% CI 0.78-1.40) and AVG abandonment, and greater relative rate of interventions after successful AVG use (RR 1.16, 95% CI 1.01-1.33). CONCLUSIONS: While AVFs should be considered the preferred vascular access in most circumstances, clinical AVF surgical outcomes are uniformly worse in females. Clinicians should also consider AVGs as a viable alternative in elderly female patients initiating hemodialysis with a CVC to avoid extended CVC dependence.

12.
Clin J Am Soc Nephrol ; 13(9): 1364-1372, 2018 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-30139806

RESUMO

BACKGROUND AND OBJECTIVES: Postoperative ultrasound is commonly used to assess arteriovenous fistula (AVF) maturation for hemodialysis, but its utility for predicting unassisted AVF maturation or primary AVF patency for hemodialysis has not been well defined. This study assessed the predictive value of postoperative AVF ultrasound measurements for these clinical AVF outcomes. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We queried a prospective vascular access database to identify 246 patients on catheter-dependent hemodialysis who underwent AVF creation between 2010 and 2016 and obtained a postoperative ultrasound within 90 days. Multivariable logistic regression was used to evaluate the association of clinical characteristics and postoperative ultrasound measurements with unassisted AVF maturation. A receiver operating characteristic curve estimated the predictive value of these factors for unassisted AVF maturation. Finally, multivariable survival analysis was used to identify factors associated with primary AVF patency in patients with unassisted AVF maturation. RESULTS: Unassisted AVF maturation occurred in 121 out of 246 patients (49%), assisted maturation in 55 patients (22%), and failure to mature in 70 patients (28%). Using multivariable logistic regression, unassisted AVF maturation was associated with AVF blood flow (odds ratio [OR], 1.30; 95% confidence interval [95% CI], 1.18 to 1.45 per 100 ml/min increase; P<0.001), forearm location (OR, 0.37; 95% CI, 0.08 to 1.78; P=0.21), presence of stenosis (OR, 0.45; 95% CI, 0.23 to 0.88; P=0.02); AVF depth (OR, 0.88; 95% CI, 0.77 to 1.00 per 1 mm increase; P=0.05), and AVF location interaction with depth (OR, 0.50; 95% CI, 0.28 to 0.84; P=0.02). The area under the receiver operating characteristic curve, using all these factors, was 0.84 (95% CI, 0.79 to 0.89; P<0.001). Primary AVF patency in patients with unassisted maturation was associated only with AVF diameter (hazard ratio, 0.84; 95% CI, 0.76 to 0.94 per 1 mm increase; P=0.002). CONCLUSIONS: Unassisted AVF maturation is predicted by AVF blood flow, location, depth, and stenosis. AVF patency after unassisted maturation is predicted only by the postoperative AVF diameter.


Assuntos
Derivação Arteriovenosa Cirúrgica , Grau de Desobstrução Vascular , Artérias/diagnóstico por imagem , Artérias/cirurgia , Feminino , Humanos , Hiperplasia/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Valor Preditivo dos Testes , Estudos Prospectivos , Túnica Íntima/diagnóstico por imagem , Túnica Íntima/patologia , Ultrassonografia , Veias/diagnóstico por imagem , Veias/cirurgia
13.
Am J Nephrol ; 47(6): 427-434, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29879718

RESUMO

BACKGROUND: Acute kidney injury (AKI) is associated with increased morbidity and mortality. Mortality in end-stage renal disease (ESRD) patients is highest during the first year of dialysis. The impact of pre-ESRD AKI events on long-term outcomes in incident ESRD patients remains unknown. METHODS: We evaluated a retrospective cohort of 47,341 incident hemodialysis patients from the United States Renal Data System with linked Medicare data for at least 2 years prior to hemodialysis initiation. We examined the impact of pre-ESRD AKI events in the 2-year pre-ESRD period on the type of vascular access used at hemodialysis initiation (central venous catheter (CVC) versus arteriovenous access), and 1-year all-cause mortality after initiating hemodialysis. RESULTS: The mean age was 72 ± 11 years. Of the study cohort, 18% initiated hemodialysis with arteriovenous access, and 54% of patients had at least one pre-ESRD AKI event. One-year, all-cause mortality was 32%. Compared to 75% for patients without a pre-ESRD AKI event, 89% of patients with a pre-ESRD AKI event initiated hemodialysis with CVC than arteriovenous access (p < 0.001). A pre-ESRD AKI event was associated with lower adjusted odds of starting hemodialysis with an arteriovenous access (OR 0.47; 95% CI 0.44-0.50, p < 0.001), and higher adjusted odds of 1-year mortality (OR 1.36; 95% CI 1.30-1.42, p < 0.001). CONCLUSION: An AKI event prior to initiating hemodialysis independently increases the risk of CVC use and predicts 1-year mortality. Improving processes of care after AKI events may improve dialysis outcomes in patients who progress to ESRD.


Assuntos
Lesão Renal Aguda/complicações , Falência Renal Crônica/mortalidade , Falência Renal Crônica/terapia , Diálise Renal , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Humanos , Masculino , Prognóstico , Estudos Retrospectivos
14.
J Vasc Surg ; 68(6): 1858-1864.e1, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29937290

RESUMO

OBJECTIVE: We have previously shown that arteriovenous fistulas (AVFs) are more expensive to create and to maintain than arteriovenous grafts (AVGs) in patients undergoing their first access. Because those for whom this first access fails may be a more disadvantaged group, we hypothesized that the cost of a second access may be different from that in the primary access group. With this in mind, we compared access costs in patients receiving a secondary AVF or AVG after their initial AVF failed to mature. METHODS: This was a retrospective cohort study of 92 patients who received a second vascular access (44 AVFs and 48 AVGs) after their first AVF failed to mature. We quantified the yearly frequency of percutaneous or surgical access interventions and catheter-related bacteremias (CRBs) using a computerized vascular access database. The costs associated with access procedures were quantified using the outpatient prospective payment schedule, and those related to hospitalization for CRB were determined from the diagnosis-related groups fee schedule. RESULTS: Patients receiving an AVF had fewer percutaneous procedures than those receiving an AVG (2.09 [95% confidence interval, 1.86-2.34] vs 2.61 [2.35-2.88]; P = .004), tended to undergo surgical interventions more frequently (1.21 [1.04-1.40] vs 1.00 [0.84-1.17]; P = .08), and experienced a similar yearly frequency of CRB hospitalizations (0.40 [0.31-0.52 vs 0.28 [0.20-0.38]; P = .07). Patients with a secondary AVF vs an AVG had a similar median yearly cost of percutaneous access interventions ($3567 [interquartile range, $1219-$4680] vs $4989 [$1570-$9752]; P = .14) and surgical access procedures ($6403 [$3494-$13,127] vs $4728 [$2563-$12,254]; P = .38) but a higher annual cost for CRBs ($3405 [$0-$12,825] vs $0 [$0-$5477]; P = .04). The total yearly access-related cost was similar in both groups ($19,477 [$9162-$36,916] vs $18,285 [$6850-$31,768]; P = .56). CONCLUSIONS: Patients undergoing a secondary AVF required more surgical procedures and sustained more bacteremia complications than patients undergoing a secondary AVG implantation. There was no significant difference in the total cost of access care for hemodialysis patients receiving a secondary AVF vs AVG.


Assuntos
Assistência Ambulatorial/economia , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Derivação Arteriovenosa Cirúrgica/economia , Implante de Prótese Vascular/economia , Custos Hospitalares , Diálise Renal/economia , Adulto , Idoso , Implante de Prótese Vascular/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/economia , Complicações Pós-Operatórias/terapia , Reoperação , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Falha de Tratamento
15.
Am J Kidney Dis ; 72(4): 509-518, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29784614

RESUMO

RATIONALE & OBJECTIVE: National vascular access guidelines recommend placement of arteriovenous fistulas (AVFs) over grafts (AVGs) in hemodialysis patients, but have not been comprehensively assessed in the elderly. We evaluated clinically relevant vascular access outcomes in elderly patients receiving an AVF or AVG after hemodialysis therapy initiation. STUDY DESIGN: Retrospective cohort study using national administrative data. SETTINGS & PARTCIPANTS: Claims data from the US Renal Data System of 9,458 US patients 67 years and older who initiated hemodialysis therapy from July 1, 2010, to June 30, 2011, with a catheter and received an AVF (n=7,433) or AVG (n=2,025) within the ensuing 6 months. PREDICTOR: Arteriovenous access subtype, AVF or AVG. OUTCOMES: Successful use of vascular access, interventions to make vascular access functional, duration of catheter dependence before successful use of vascular access, frequency of interventions, and abandonment after successful use of vascular access. ANALYTICAL APPROACH: Multivariable logistic regression analysis was used to compare the need for intervention before successful use of AVFs and AVGs, and negative bionomial regression was used to calculate the frequency of intervention after successful use of vascular access. RESULTS: Unsuccessful use of vascular access within 6 months of creation was higher for AVFs versus AVGs (51% vs 45%; adjusted HR, 1.86; 95% CI, 1.73-1.99). Interventions to make vascular access functional were greater in AVFs versus AVGs (42% vs 23%; OR, 2.66; 95% CI, 2.26-3.12). AVFs had a lower 1-year abandonment rate after successful use compared with AVGs (OR, 0.71; 95% CI, 0.62-0.83) and required one-fourth fewer interventions after successful use (relative risk, 0.75; 95% CI, 0.69-0.81). Patients receiving an AVF had substantially longer catheter dependence before successful use than those receiving an AVG (median time, 3 vs 1 month; P<0.001). LIMITATIONS: Residual confounding due to vascular access choice, restriction to an elderly population, and 1-year follow-up period. CONCLUSIONS: In elderly hemodialysis patients initiating hemodialysis therapy with a catheter, the optimal vascular access selection depends on tradeoffs between shorter catheter dependence and less frequent interventions to make the vascular access (AVG) functional versus longer access patency and fewer interventions after successful use of the vascular access (AVF).


Assuntos
Derivação Arteriovenosa Cirúrgica/efeitos adversos , Oclusão de Enxerto Vascular/epidemiologia , Falência Renal Crônica/terapia , Diálise Renal/métodos , Dispositivos de Acesso Vascular/efeitos adversos , Grau de Desobstrução Vascular/fisiologia , Idoso , Idoso de 80 Anos ou mais , Cateterismo/efeitos adversos , Cateterismo/métodos , Estudos de Coortes , Bases de Dados Factuais , Feminino , Seguimentos , Avaliação Geriátrica , Humanos , Estimativa de Kaplan-Meier , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/mortalidade , Masculino , Análise Multivariada , Segurança do Paciente , Diálise Renal/efeitos adversos , Estudos Retrospectivos , Medição de Risco , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
16.
Am J Kidney Dis ; 72(1): 10-18, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29602630

RESUMO

BACKGROUND: An arteriovenous fistula (AVF) is the recommended vascular access for hemodialysis (HD). Previous studies have not examined the resources and costs associated with creating and maintaining AVFs. STUDY DESIGN: Retrospective observational study. SETTING & PARTICIPANTS: Elderly US Medicare patients initiating hemodialysis therapy during 2010 to 2011. PREDICTOR: AVF primary and secondary patency and nonuse in the first year following AVF creation. OUTCOMES: Annualized vascular access costs per patient per year. RESULTS: Among patients with only a catheter at HD therapy initiation, only 54% of AVFs were successfully used for HD, 10% were used but experienced secondary patency loss within 1 year of creation, and 83% experienced primary patency loss within 1 year of creation. Mean vascular access costs per patient per year in the 2.5 years after AVF creation were $7,871 for AVFs that maintained primary patency in year 1, $13,282 for AVFs that experienced primary patency loss in year 1, $17,808 for AVFs that experienced secondary patency loss in year 1, and $31,630 for AVFs that were not used. Similar patterns were seen among patients with a mature AVF at HD therapy initiation and patients with a catheter and maturing AVF at HD therapy initiation. Overall, in 2013, fee-for-service Medicare paid $2.8 billion for dialysis vascular access-related services, ∼12% of all end-stage renal disease payments. LIMITATIONS: Lack of granularity with certain billing codes. CONCLUSIONS: AVF failure in the first year after creation is common and results in substantially higher health care costs. Compared with patients whose AVFs maintained primary patency, vascular access costs were 2 to 3 times higher for patients whose AVFs experienced primary or secondary patency loss and 4 times higher for patients who never used their AVFs. There is a need to improve AVF outcomes and reduce costs after AVF creation.


Assuntos
Derivação Arteriovenosa Cirúrgica/economia , Custos de Cuidados de Saúde , Falência Renal Crônica/economia , Falência Renal Crônica/terapia , Medicare/economia , Diálise Renal/economia , Idoso , Idoso de 80 Anos ou mais , Derivação Arteriovenosa Cirúrgica/tendências , Estudos de Coortes , Feminino , Custos de Cuidados de Saúde/tendências , Humanos , Falência Renal Crônica/diagnóstico , Masculino , Medicare/tendências , Diálise Renal/tendências , Estudos Retrospectivos , Estados Unidos/epidemiologia
17.
Am J Kidney Dis ; 71(5): 690-700, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29478866

RESUMO

Vascular access outcomes in hemodialysis are critically important for patients and clinicians, but frequently are neither patient relevant nor measured consistently in randomized trials. A Standardized Outcomes in Nephrology-Hemodialysis (SONG-HD) consensus workshop was convened to discuss the development of a core outcome measure for vascular access. 13 patients/caregivers and 46 professionals (clinicians, policy makers, industry representatives, and researchers) attended. Participants advocated for vascular access function to be a core outcome based on the broad applicability of function regardless of access type, involvement of a multidisciplinary team in achieving a functioning access, and the impact of access function on quality of life, survival, and other access-related outcomes. A core outcome measure for vascular access required demonstrable feasibility for implementation across different clinical and trial settings. Participants advocated for a practical and flexible outcome measure with a simple actionable definition. Integrating patients' values and preferences was warranted to enhance the relevance of the measure. Proposed outcome measures for function included "uninterrupted use of the access without the need for interventions" and "ability to receive prescribed dialysis," but not "access blood flow," which was deemed too expensive and unreliable. These recommendations will inform the definition and implementation of a core outcome measure for vascular access function in hemodialysis trials.


Assuntos
Consenso , Diálise Renal/normas , Dispositivos de Acesso Vascular/normas , Educação , Feminino , Humanos , Masculino , Nefrologia/normas , Padrões de Referência
18.
Clin J Am Soc Nephrol ; 13(3): 501-512, 2018 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28729383

RESUMO

This paper is part of the Clinical Trial Endpoints for Dialysis Vascular Access Project of the American Society of Nephrology Kidney Health Initiative. The purpose of this project is to promote research in vascular access by clarifying trial end points which would be best suited to inform decisions in those situations in which supportive clinical data are required. The focus of a portion of the project is directed toward arteriovenous access. There is a potential for interventional studies to be directed toward any of the events that may be associated with an arteriovenous access' evolution throughout its life cycle, which has been divided into five distinct phases. Each one of these has the potential for relatively unique problems. The first three of these correspond to three distinct stages of arteriovenous access development, each one of which has been characterized by objective direct and/or indirect criteria. These are characterized as: stage 1-patent arteriovenous access, stage 2-physiologically mature arteriovenous access, and stage 3-clinically functional arteriovenous access. Once the requirements of a stage 3-clinically functional arteriovenous access have been met, the fourth phase of its life cycle begins. This is the phase of sustained clinical use from which the arteriovenous access may move back and forth between it and the fifth phase, dysfunction. From this phase of its life cycle, the arteriovenous access requires a maintenance procedure to preserve or restore sustained clinical use. Using these definitions, clinical trial end points appropriate to the various phases that characterize the evolution of the arteriovenous access life cycle have been identified. It is anticipated that by using these definitions and potential end points, clinical trials can be designed that more closely correlate with the goals of the intervention and provide appropriate supportive data for clinical, regulatory, and coverage decisions.


Assuntos
Derivação Arteriovenosa Cirúrgica , Determinação de Ponto Final , Mãos/irrigação sanguínea , Isquemia/diagnóstico , Enxerto Vascular , Veias/patologia , Aneurisma/diagnóstico , Aneurisma/etiologia , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Ensaios Clínicos como Assunto , Constrição Patológica/etiologia , Humanos , /etiologia , Isquemia/etiologia , Diálise Renal , Trombose/diagnóstico , Trombose/etiologia , Enxerto Vascular/efeitos adversos
19.
J Vasc Access ; 19(2): 167-171, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29283177

RESUMO

INTRODUCTION: Arteriovenous fistulas (AVF) frequently fail to mature. Postoperative ultrasounds provide objective measurements to predict unassisted AVF use for hemodialysis (unassisted use) and guide interventions to salvage nonmaturing AVFs. The optimal ultrasound criteria to assess AVF maturation are uncertain. We analyzed data from a multicenter, randomized, controlled, clinical trial to compare 2 published ultrasound maturation criteria used to predict unassisted AVF use for hemodialysis. METHODS: We retrospectively analyzed prospective data on 105 patients undergoing new AVF creation, who underwent standardized postoperative ultrasounds at 6 and 12 weeks to measure AVF diameter and blood flow. Unassisted AVF use was defined as successful cannulation for ≥90 days without requiring prior surgical or percutaneous interventions. Two ultrasound criteria were assessed: (i) National Kidney Foundation (NKF) Kidney Disease Outcome Quality Initiative criteria: AVF outflow vein lumen diameter ≥6 mm and blood flow ≥600 mL/min; and (ii) University of Alabama at Birmingham (UAB) criteria: AVF outflow vein lumen diameter ≥4 mm and blood flow ≥500 mL/min. Performance characteristics were calculated for both criteria. RESULTS: Compared to the NKF criteria, the UAB criteria had a higher sensitivity (89 vs.68%), but a lower specificity (42 vs. 70%) for unassisted AVF use. For radiocephalic AVFs, the UAB criteria had higher sensitivity (86 vs. 46%) and lower specificity (58 vs. 83%). For brachiocephalic AVFs, both UAB and NKF had high sensitivity (90 and 80%) but low specificity (21 and 53%), respectively. CONCLUSIONS: Using the UAB ultrasound criteria would minimize unnecessary early interventions in AVFs likely to mature without an intervention, but would delay interventions in AVFs that are unlikely to mature. The UAB criteria may be preferred in patients receiving a radiocephalic AVF.


Assuntos
Derivação Arteriovenosa Cirúrgica , Diálise Renal , Ultrassonografia Doppler Dupla , Extremidade Superior/irrigação sanguínea , Grau de Desobstrução Vascular , Idoso , Derivação Arteriovenosa Cirúrgica/efeitos adversos , Velocidade do Fluxo Sanguíneo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Valor Preditivo dos Testes , Ensaios Clínicos Controlados Aleatórios como Assunto , Fluxo Sanguíneo Regional , Reprodutibilidade dos Testes , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
20.
Am J Kidney Dis ; 71(3): 382-391, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29203125

RESUMO

BACKGROUND: Many randomized controlled trials have been performed with the goal of improving outcomes related to hemodialysis vascular access. If the reported outcomes are relevant and measured consistently to allow comparison of interventions across trials, such trials can inform decision making. This study aimed to assess the scope and consistency of vascular access outcomes reported in contemporary hemodialysis trials. STUDY DESIGN: Systematic review. SETTING & POPULATION: Adults requiring maintenance hemodialysis. SELECTION CRITERIA: All randomized controlled trials and trial protocols reporting vascular access outcomes identified from ClinicalTrials.gov, Embase, MEDLINE, and the Cochrane Kidney and Transplant Specialized Register from January 2011 to June 2016. INTERVENTIONS: Any hemodialysis-related intervention. OUTCOMES: The frequency and characteristics of vascular access outcome measures were analyzed and classified. RESULTS: From 168 relevant trials, 1,426 access-related outcome measures were extracted and classified into 23 different outcomes. The 3 most common outcomes were function (136 [81%] trials), infection (63 [38%]), and maturation (31 [18%]). Function was measured in 489 different ways, but most frequently reported as "mean access blood flow (mL/min)" (37 [27%] trials) and "number of thromboses" (30 [22%]). Infection was assessed in 136 different ways, with "number of access-related infections" being the most common measure. Maturation was assessed in 44 different ways at 15 different time points and most commonly characterized by vein diameter and blood flow. Patient-reported outcomes, including pain (19 [11%]) and quality of life (5 [3%]), were reported infrequently. Only a minority of trials used previously standardized outcome definitions. LIMITATIONS: Restricted sampling frame for feasibility and focus on contemporary trials. CONCLUSIONS: The reporting of access outcomes in hemodialysis trials is very heterogeneous, with limited patient-reported outcomes and infrequent use of standardized outcome measures. Efforts to standardize outcome reporting for vascular access are critical to optimizing the comparability, reliability, and value of trial evidence to improve outcomes for patients requiring hemodialysis.


Assuntos
Falha de Equipamento/estatística & dados numéricos , Falência Renal Crônica/terapia , Diálise Renal/métodos , Dispositivos de Acesso Vascular/efeitos adversos , Adulto , Fatores Etários , Feminino , Humanos , Incidência , Internacionalidade , Falência Renal Crônica/diagnóstico , Falência Renal Crônica/mortalidade , Manutenção , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Diálise Renal/efeitos adversos , Medição de Risco , Fatores Sexuais , Taxa de Sobrevida , Fatores de Tempo
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