Antiplatelet medications in hemodialysis patients: a systematic review of bleeding rates

Pathological evaluation of a fluoropolymer-based drug-eluting stent in an arteriovenous graft outflow venous stenosis

A fluoropolymer-based drug-eluting stent was implanted in an arteriovenous graft outflow venous stenosis. Two and a half years later, due to a local infection, the stent was removed surgically, and a pathological evaluation was conducted. The stent struts exhibited partial endothelial cell coverage, with the remaining surface predominantly covered by fibrin. Notably, there was no evidence of restenosis or aneurysmal change.

Long-term safety and efficacy of left atrial appendage occlusion in dialysis patients with atrial fibrillation: a multi-center, prospective, open label, observational study

Background

The prevalence of atrial fibrillation (AF) in end stage kidney disease (ESKD) patients undergoing dialysis is high, however, the high risk of bleeding often hampers with a correct anticoagulation in ESKD patients with AF, despite high thromboembolic risk. Left atrial appendage (LAA) occlusion is a anticoagulation (OAT) for thromboembolism prevention in AF populations with high hemorrhagic risk.

Methods and Results

The purpose of the study was to evaluate the efficacy and safety of LAA occlusion in a cohort of dialysis patients undergoing the procedure (LAA occlusion cohort, n = 106), in comparison with two other ESKD cohorts, one taking warfarin (Warfarin cohort, n = 114) and the other without anticoagulation therapy (No-OAT cohort, n = 148). After a median follow-up of 4 years, a Cox regression model, adjusted for possible confounding factors, showed that the hazard ratios (HRs) of thromboembolic events in the LAA occlusion cohort were 0.19 (95%CI 0.04-0.96; p = 0.045) and 0.16 (95%CI 0.04-0.66; p = 0.011) as compared with Warfarin and No-OAT cohorts, respectively. The HR of bleeding in the LAA occlusion cohort was 0.37 (95%CI 0.16-0.83; p = 0.017) compared to Warfarin cohort, while there were no significant differences between the LAA occlusion and the No-OAT cohort (HR 0.51; 95%CI 0.23-1.12; p = 0.094). Adjusted Cox regression models showed lower mortality in patients undergoing LAA occlusion as compared with both the Warfarin cohort (HR 0.60; 95%CI 0.38-0.94; p = 0.027) and no-OAT cohort (HR 0.52; 95%CI 0.34-0.78; p = 0.002). Thromboembolic events in the LAA occlusion cohort were lower than expected according to the CHA2DS2VASc score (1.7 [95%CI 0.3-3.0] vs 6.7 events per 100 person/years, p < 0.001).

Conclusion

In ESKD patients with AF, LAA occlusion is safe and effective and is associated with reduced mortality compared with OAT or no therapy.

Bleeding Risk in Hemodialysis Patients

Cardiovascular diseases are highly prevalent among patients on dialysis. For these diseases, antiplatelets and antithrombotic therapies including heparin, vitamin K antagonists, and direct oral anticoagulants, are being used. However, the benefit-risk balance of these therapies could differ for dialysis patients compared with the general population. This review article focuses on the bleeding risk associated with the use of heparin, antiplatelets, vitamin K antagonists, and direct oral anticoagulants in patients receiving hemodialysis.

A Case of Pituitary Apoplexy and Cavernous Sinus Syndrome during Hemodialysis

Background

Pituitary apoplexy (PA) is a clinical syndrome of pituitary hemorrhage or infarction and can result in hypopituitarism as well as compression of adjacent brain structures. Visual loss occurs frequently, as a result of tumor expansion and compression of the optic chiasm and optic nerves. Additionally, with pituitary tumor invasion into the fixed space of the cavernous sinus, compression of multiple cranial nerves can result in cavernous sinus syndrome (CSS). We describe a case of an undiagnosed pituitary tumor manifesting as abrupt PA with CSS during hemodialysis (HD). Clinical Case. A 77-year-old male with end-stage renal disease (ESRD) presented with acute onset of severe headache, decreased vision, ophthalmoplegia of the left eye, and hypotension during HD. MRI of the brain revealed a 2.5 cm pituitary adenoma with acute hemorrhage, compression of the left prechiasmatic optic nerve, and invasion into the left cavernous sinus (CS). The hormonal profile was consistent with multiple pituitary hormone deficiencies. The patient was treated with glucocorticoids and underwent transsphenoidal resection of the tumor. He had an uneventful postoperative hospital course, and his left visual acuity stabilized, although there was no immediate improvement in his other ocular symptoms.

Conclusion

Our case highlights a rare constellation of a pituitary adenoma with CS invasion complicated by PA and CSS during HD. The pathophysiology of PA is not well understood, and there are very limited data regarding PA in patients with end-stage renal disease (ESRD) on HD. Prompt recognition of PA in a patient presenting with CSS, particularly in the HD setting, is essential to ensure appropriate care is provided for this medical emergency.

The Performance of Risk Scores for Bleeding and Ischemia as Outcome Predictors in Acute Myocardial Infarction Patients with End-Stage Renal Disease

BACKGROUND

In patients with end-stage renal disease (ESRD), acute myocardial infarction (AMI) increases the risks of cardiovascular events, death, and bleeding. Several scores have been developed for predicting ischemic and bleeding outcomes in AMI patients, but none have been validated specifically for ESRD patients.

OBJECTIVES

To compare and validate different risk scores as predictors of ischemic and bleeding outcomes in AMI patients with ESRD.

METHODS

This retrospective study enrolled 340 patients who had received percutaneous coronary intervention for AMI while undergoing maintenance hemodialysis for ESRD. Ischemic risk scores (TIMI-STEMI, TIMI-NSTEMI, GRACE, DAPT) and bleeding risk scores (PRECISE-DAPT, CRUSADE, ACUITY, ACTION, SWEDEHEART) were calculated. The ischemic outcome mainly focused on major adverse cardiovascular events (MACEs) within 14 days after hospitalization, and the bleeding outcome was 14-day major bleeding according to the CRUSADE criteria.

RESULTS

The GRACE score was superior in discriminating ischemic outcomes, especially in 14-day MACEs [area under curve (AUC) 0.791, p < 0.001]. None of the scores could ideally discriminate 14-day CRUSADE major bleeding, while the PRECISE- DAPT score had the best discriminative power (AUC 0.636, p < 0.001). Either GRACE score > 222 or PRECISE-DAPT score > 48 was associated with higher net adverse cardiovascular events (a composite of 14-day MACEs and 14-day CRUSADE major bleeding).

CONCLUSIONS

In AMI patients with ESRD, the GRACE score can effectively discriminate the risk of short-term ischemic events. None of the scores could ideally discriminate the bleeding risk, but a high PRECISE-DAPT score still represented a higher rate of bleeding events.

Age Modifies Intracranial and Gastrointestinal Bleeding Risk from P2Y12 Inhibitors in Patients Receiving Dialysis

Background

Individuals aged ≥75 years are the fastest-growing population starting dialysis for end-stage kidney disease (ESKD) due to living longer with coronary artery disease. ESKD alone can increase bleeding risk, but P2Y₁₂ inhibitor (P2Y12-I) antiplatelet medications prescribed for cardiovascular treatment can exacerbate this risk in patients with ESKD. The age-specific rates of bleeding complications in dialysis patients with ESKD on P2Y12-I remain unclear, as does how age modifies the bleeding risk from P2Y12-I use in these patients.

Methods

In a retrospective cohort study, we collected data on 40,972 patients receiving maintenance hemo- or peritoneal dialysis who were newly prescribed P2Y12-I therapy between 2011 and 2015 from the USRDS registry. We analyzed the effect of age on the time to first bleed and the interactions between age and P2Y12-I type on modifying the effects of a bleed.

Results

Twenty percent of the cohort were aged ≥75 years. There were 3096 (8%) gastrointestinal (GI) and 1298 (3%) intracranial (IC) bleeding events during a median follow-up of 1 year. Annual incidence rates for IC bleeds were 2% in those aged <55 years and 3% in those aged ≥75 years. Rates for GI bleeds were 4% in those aged <55 years and 9% in those aged ≥75 years. On clopidogrel, prasugrel, and ticagrelor, for every decade increase in age of the cohort members, the risk of IC bleed increased by 9%, 55%, and 59%, and the risk of GI bleed increased by 21%, 28%, and 39%, respectively. At age ≥75 years, prasugrel was associated with a greater risk of IC bleed than clopidogrel. At age ≥60 years, ticagrelor was associated with a greater risk of GI bleed than clopidogrel.

Conclusions

More potent P2Y12-Is (prasugrel and ticagrelor) were associated with a disproportionately higher risk of IC bleed with increasing age compared with that of clopidogrel-prasugrel was much worse than clopidogrel at age ≥75 years. All three drugs were associated with only modest increase in the risk of GI bleed with every decade increase in age-ticagrelor was much worse than clopidogrel at ≥60 years of age. These results highlight the need for head-to-head clinical trials for the use of P2Y12-Is in patients with ESKD to determine age cutoffs where the risk of bleeding outweighs the benefits of thrombosis prevention.

Comparative Effectiveness and Safety of Oral P2Y12 Inhibitors in Patients on Chronic Dialysis

Introduction

Although oral P2Y₁₂ inhibitors (P2Y12-Is) are one of the most commonly prescribed medication classes in patients with end stage kidney disease on dialysis (ESKD), scarce data exist regarding their benefits and risks.

Methods

We compared effectiveness and safety of clopidogrel, prasugrel, and ticagrelor in a longitudinal study using the United States Renal Data System registry of Medicare beneficiaries with ESKD. Individuals who filled new P2Y12-I prescriptions between 2011 and 2015 were included and followed until death or censoring. The primary exposure variable was P2Y12-I assignment. The primary outcome variable was death. Secondary outcomes included cardiovascular (CV) death, coronary revascularization, and gastrointestinal (GI) hemorrhage. Survival analyses were performed after propensity matching.

Results

Of 44,619 patients with ESKD who received P2Y12-Is, 95% received clopidogrel (n = 42,523), 3% prasugrel (n = 1205), and 2% ticagrelor (n = 891). To balance baseline differences, propensity-matching was performed: 1:6 for prasugrel (n = 1189) versus clopidogrel (n = 7134); 1:4 for ticagrelor (n = 880) versus clopidogrel (n = 3520); and 1:1 for ticagrelor versus prasugrel (n = 880). Prasugrel was associated with a reduced risk for death versus clopidogrel and ticagrelor (adjusted hazard ratio [HR] = 0.82; 95% CI: 0.73–0.93 and 0.78; 95% CI: 0.64–0.95). Compared with clopidogrel, prasugrel reduced risk for coronary revascularization (HR = 0.91; 95% CI: 0.86–0.96). There were no differences in GI hemorrhage between P2Y12-Is.

Conclusion

In patients with ESKD, prasugrel compared with others reduced risk of death possibly by reducing risk for coronary revascularizations and without worsening gastrointestinal hemorrhage. Future trials are imperative to compare efficacy and safety of P2Y12-Is in patients with ESKD.

Role of Platelets in Chronic Kidney Disease

Platelet-dependent mechanisms for excessive clotting and bleeding in CKD remain undefined. Moreover, platelets' contribution to inflammation, and specifically to CKD, are equally elusive. To date, descriptions of changes in the functional properties of circulating platelets during CKD have provided confusing interpretations. Experimental approaches that can advance our understanding of platelet dysfunction in CKD are needed, and studies that provide mechanistic insights into the dynamic relationships between thrombosis, bleeding, and inflammation associated with CKD will be essential to improve clinical management and outcomes for this vulnerable population. This article summarizes existing literature characterizing platelets in CKD and identifies areas that need further investigation.

A retrospective study of antithrombotic therapy use in an outpatient haemodialysis unit

WHAT IS KNOWN AND OBJECTIVE

Patients on haemodialysis (HD) are at increased risk of both bleeding and thrombotic events, due to comorbidities and nature of dialysis treatment. However, there is a lack of research on evidence-based treatment strategies and prescribing patterns for antithrombotic therapies (ATT) in this population. To characterize ATT use and its main indications in an outpatient HD unit.

METHODS

A single-centre retrospective chart review was conducted in a Toronto outpatient HD unit (n = 329). Medical histories, number of ATTs and corresponding indications were collected from adult patients prescribed at least one ATT from 1 October 2019 to 31 December 2019, inclusive.

RESULTS AND DISCUSSION

Of 329 patients in the unit, a total of 135 (41%) patients were on at least one ATT. Of these 135 patients, 80% were on monotherapy (55% antiplatelet, 25.1% anticoagulant), 12.6% were on dual antiplatelet therapy (DAPT), and 7.4% were on a antiplatelet and anticoagulant combination. Primary indications for ATT in our cohort were coronary artery disease (CAD; 55%), atrial fibrillation (18.5%) and venous thromboembolism (VTE; 17%). Described ATT use was in-line with current clinical guidelines. Monotherapy was primarily used in our HD cohort, whereas few patients were on dual therapy. Low-dose aspirin was the most common antiplatelet prescribed for secondary prevention of cardiovascular events. Warfarin monotherapy was primarily indicated for VTE, and DAPT aspirin/clopidogrel was the most commonly prescribed for CAD.

WHAT IS NEW AND CONCLUSION

Our characterization of ATT use in this HD cohort demonstrates that ATT is often prescribed for a number of different CVD reasons. Overlapping and confounding indications for prescribing ATTs, lack of randomized controlled trials and unclear clinical guidelines mean that individualized risk-benefit assessments for ATT use are still needed to provide care for these high-risk patients. More research to address the safety and efficacy of ATTs is warranted to develop more robust evidence-based treatment guidelines for the HD population.

Nonsteroidal anti-inflammatory drugs in end-stage kidney disease: dangerous or underutilized?

Introduction: Nonsteroidal anti-inflammatory drugs (NSAIDs) are a popular class of analgesic and anti-inflammatory medications, but their use is often avoided in end-stage kidney disease (ESKD) patients due to their reputation for nephrotoxic side effects. This removes a useful agent from the analgesic arsenal, even as ESKD patients suffer from proportionally more severe chronic pain than the general population as well as from a large reliance on opioid medications. Areas Covered: This paper reviews the current literature to comprehensively define the pharmacologic mechanisms and adverse effects of NSAIDs and reassesses the viability of their use in ESKD patients. Expert opinion: The evidence directly examining the impact of NSAIDs on long-term outcomes in ESKD is limited. Further study quantifying the risk of NSAID use - especially in dialysis-dependent patients - is warranted. Given the difficulty in achieving adequate pain control in ESKD patients, limited use of NSAIDs in these patients may yet be justified.

Clinical outcomes of prolonged dual antiplatelet therapy after coronary drug-eluting stent implantation in dialysis patients

Background

End-stage renal disease yields susceptibility to both ischemia and bleeding. The optimal duration of dual antiplatelet therapy (DAPT) after drug-eluting stent (DES) implantation is not established in dialysis patients, who are usually excluded from randomized studies. Since recent studies implied the benefits of prolonged DAPT >12 months in chronic kidney disease, we investigated the effectiveness and safety of prolonged DAPT in dialysis patients with higher cardiovascular risks.

Methods

In this nationwide population-based study, we analyzed dialysis patients who underwent DES implantation from 2008 to 2015. Continued DAPT was compared with discontinued DAPT using landmark analyses, including free-of-event participants at 12 (n = 2246), 15 (n = 1925) and 18 months (n = 1692) after DES implantation. The primary outcome was major adverse cardiovascular events (MACEs): a composite of mortality, nonfatal myocardial infarction, coronary revascularization and stroke. Major bleeding was a safety outcome. Inverse probability of treatment weighting Cox regression was performed.

Results

Mean follow-up periods were 278.3-292.4 days, depending on landmarks. Overall, incidences of major bleeding were far lower than those of MACE. Continued DAPT groups showed lower incidences of MACE and higher incidences of major bleeding, compared with discontinued DAPT groups. In Cox analyses, continued DAPT reduced the hazards of MACE at the 12- [hazard ratio (HR) = 0.74, 95% confidence interval (CI) 0.61-0.90; P = 0.003], 15- (HR = 0.78, 95% CI 0.64-0.96; P = 0.019) and 18-month landmarks (HR = 0.79, 95% CI 0.63-0.99; P = 0.041), but without a significant increase in major bleeding at 12 (HR = 1.39, 95% CI 0.90-2.16; P = 0.14), 15 (HR = 1.13, 95% CI 0.75-1.70; P = 0.55) or 18 months (HR = 1.27, 95% CI 0.83-1.95; P = 0.27).

Conclusions

Prolonged DAPT reduced MACE without significantly increasing major bleeding in patients who were event-free at 12 months after DES implantation. In deciding on DAPT duration, prolonged DAPT should be considered in dialysis patients.

The risk of bleeding for antiplatelet agents in Haemodialysis patients: a Meta-analysis

Background

The safety of antiplatelet therapy in haemodialysis (HD) patients remains controversial. we conducted the first meta-analysis to evaluate the bleeding risk with antiplatelet agents in these populations.

Methods

The relevant literature was searched using the following electronic databases without any language restrictions: the Cochrane Library, EMBASE, Global Health, MEDLINE, PubMed, and the Chinese Biomedical Database.

Results

Seven randomized controlled trials (RCTs) and 2 prospective cohort studies, consisting of 1131 patients, were identified for detailed evaluation. The meta-analysis suggested that the use of double antiplatelet agents increased the risk of bleeding in HD patients [odds ratio (OR) = 2.78; 95% confidence interval (CI) 1.63 to 4.76; I² = 0], and antiplatelet agents increased the risk of bleeding in 7 RCTs [odds ratio (RR) = 1.40, 95% CI 1.08 to 1.79; I² = 23%,]; however, the use of a single antiplatelet agent was not found to significantly increase the risk of bleeding (RR = 0.88; 95% CI 0.51 to 1.50; I² = 0).

Conclusion

The results suggested that the use of double antiplatelet agents increased the risk of bleeding in HD patients.

Trends for and Clinical Factors Associated with Choice of Oral P2Y12 Inhibitors for Patients on Chronic Dialysis

Background

Trends and clinical factors associated with prescribing choices for oral P2Y12 inhibitors (P2Y12-I) remain unknown for patients on chronic dialysis, i.e., with end-stage renal disease (ESRD).

Methods

From 2011–2014 U.S. Renal Data System registry, we identified 36,542 ESRD patients who received new prescriptions for P2Y12-I (median age 64.0 years and 54% males). Of the cohort, 93% were receiving hemodialysis and 7% on peritoneal dialysis. We analyzed trends and investigated clinical factors associated with specific P2Y12-I prescribed.

Results

Clopidogrel was prescribed for 95%, prasugrel for 3%, and ticagrelor for 2%. Clopidogrel was favored for those ≥75 years (18% of cohort). Compared to Caucasians, African Americans (36% of cohort) and Hispanics (19% of cohort) were less likely to receive prasugrel and ticagrelor (P<0.05). Patients receiving hemodialysis versus peritoneal dialysis were less likely to receive prasugrel over clopidogrel, adjusted odds ratio (aOR) 0.67 (0.55-0.82). Each additional year of dialysis decreased the odds of receiving prasugrel over clopidogrel, aOR 0.91 (0.85-0.98). History of atrial fibrillation reduced the odds of receiving ticagrelor or prasugrel over clopidogrel, aOR 0.69 (0.54-0.89) and 0.73 (0.60-0.89), respectively. Concomitant oral anticoagulant use was not associated with choice of P2Y12-I. Occurrence of non-ST segment elevation myocardial infarction or percutaneous coronary intervention within the 6-month period prior to the index date favored ticagrelor over prasugrel, aOR 1.31 (1.06-1.62) and 1.29 (1.01-1.66), respectively. However, prescribing trends favoring ticagrelor over prasugrel were not observed for deployment of drug-eluting, or multiple coronary stents.

Conclusion

Between 2011 and 2014, clopidogrel remained the most common P2Y12-I whereas ticagrelor and prasugrel remained underutilized in ESRD patients. Prescribing practices for these drugs were based upon clinically approved indication for their use in the general population as well as perceived complexity of an ESRD patient including demographics, dialysis-related factors and comorbidities. Comparative effectiveness studies involving ESRD patients are needed to prove that ticagrelor and prasugrel are just as safe and effective as clopidogrel before clinicians can make informed decisions for choice of P2Y12-I in this patient population.

Electronic supplementary material

The online version of this article (10.1007/s10557-019-06913-w) contains supplementary material, which is available to authorized users.

Treatment of failing arterio-venous dialysis graft by angioplasty, stent, and stent graft: Two-years analysis of patency rates and cost-effectiveness

The objective of this prospective randomized single-center study was to compare primary and secondary patency rates, number of percutaneous transluminal angioplasty (PTA) interventions and cost-effectiveness among PTA, deployment of a stent, or a stent graft in the treatment of failing arteriovenous dialysis grafts (AVG) due to restenosis in the venous anastomosis or the outflow vein. Altogether 60 patients with failing AVG and restenosis in the venous anastomosis or the outflow vein were randomly assigned to either PTA, placement of a stent (E-Luminexx^®) or stent graft (Fluency Plus^®). After the procedure, patients with stent or stent graft received dual antiplatelet therapy for the next three months. Follow-up angiography was scheduled at 3, 6, and 12 months unless requested earlier due to suspected stenosis or malfunction of the access. Subsequently, angiography was performed only if requested by the clinician. During a median follow-up of 22.4 (IQR=5.7) months patients with PTA, stent, or stent graft required 3.1±1.7, 2.5±1.7, or 1.7±2.1 (P=0.031) secondary PTA interventions. The primary patency rates were 0, 18 and 65% at 12 months and 0, 18 and 37% at 24 months in the PTA, stent, and stent graft group respectively (P<0.0001). The cost of the procedures in the first two years was €7,900±€3,300 in the PTA group, €8,500±€4,500 in the stent group, and €7,500±€6,200 in the stent graft group (P=0.45). We conclude that the treatment of failing dialysis vascular access by the deployment of a stent graft significantly improves its primary patency rates and decreases the number of secondary PTA interventions; however, the reduction in costs for maintaining AVG patency is not significant.

Diagnosis and treatment of myocardial infarction in patient with end - stage renal disease on chronic hemodialysis

This review represents different aspects of myocardial infarction in patient with end - stage renal disease on chronic hemodialysis. We discuss difficulties in diagnosis, optimal method of coronary revascularization, timing of hemodialysis session, medical therapy, as well as epidemiology and prognosis. There are no unambiguous answers to these problems because patients with end - stage renal disease were excluded from most of the studies.

A focused review on optimal coronary revascularisation in patients with chronic kidney disease: Coronary revascularisation in kidney disease

Concomitant chronic kidney disease (CKD) and coronary artery disease (CAD) is known to have poor outcomes. With a thorough literature review, we discuss the pathophysiological basis behind accelerated atherosclerosis in CKD, and the role of percutaneous coronary intervention (PCI) in these patients, focusing on drug-eluting stents, coronary artery bypass grafting, and adverse outcomes. We discuss factors contributing to poor outcomes in these patients, and the need for more work in this subgroup.

Effects of Pre-Existing Comorbidities on Outcomes in Patients with Chronic Subdural Hematoma

OBJECTIVE

The number of patients with chronic subdural hematoma (CSDH) showing comorbidities and/or impaired activities of daily living (ADL) before the onset of CSDH has increased with the recent aging of society. The purposes of this study were to evaluate ADL worsening by comparing premorbid ADL and ADL at discharge and to investigate the effects of pre-existing comorbidity-related clinical factors on the outcomes.

METHODS

A total of 570 patients with CSDH admitted from 2006 to 2016 were studied retrospectively. Clinical factors, including pre-existing comorbidities, related to outcomes were identified by multivariate analysis. A variation of the modified Rankin Scale (mRS) using 5 united categories of mRS scores 0/1, 2, 3/4, 5, and dead was used for evaluation of ADL.

RESULTS

Of 570 patients, 390 (68.4%) had pre-existing comorbidities and 120 (21.1%) showed premorbid impaired ADL (mRS scores 2 and worse). Considering pre-existing impaired ADL, ADL deteriorated after CSDH in 92 patients (16.1%), whereas ADL impairment at discharge was found in 173 patients (30.4%). Comorbidities related to ADL deterioration on multivariate analysis were hemodialysis and chronic heart failure. Antithrombotic use for cardiovascular diseases was a predictor of acute-on-chronic subdural hematoma, which was the sole common predictor for ADL deterioration and the occurrence of surgical complications.

CONCLUSIONS

In patients with CSDH, pre-existing comorbidity-linked factors related to outcomes were hemodialysis, chronic heart failure, and antithrombotic use. Patients with acute-on-chronic subdural hematoma with these factors should be regarded as a high-risk group.

Spanish Clinical Guidelines on Vascular Access for Haemodialysis

Vascular access for haemodialysis is key in renal patients both due to its associated morbidity and mortality and due to its impact on quality of life. The process, from the creation and maintenance of vascular access to the treatment of its complications, represents a challenge when it comes to decision-making, due to the complexity of the existing disease and the diversity of the specialities involved. With a view to finding a common approach, the Spanish Multidisciplinary Group on Vascular Access (GEMAV), which includes experts from the five scientific societies involved (nephrology [S.E.N.], vascular surgery [SEACV], vascular and interventional radiology [SERAM-SERVEI], infectious diseases [SEIMC] and nephrology nursing [SEDEN]), along with the methodological support of the Cochrane Center, has updated the Guidelines on Vascular Access for Haemodialysis, published in 2005. These guidelines maintain a similar structure, in that they review the evidence without compromising the educational aspects. However, on one hand, they provide an update to methodology development following the guidelines of the GRADE system in order to translate this systematic review of evidence into recommendations that facilitate decision-making in routine clinical practice, and, on the other hand, the guidelines establish quality indicators which make it possible to monitor the quality of healthcare.

Effect of low dose aspirin and dipyridamole on primary patency of arteriovenous grafts in hemodialysis patients: a randomized double-blind placebo-controlled trial

Background

There is some evidence for the efficacy of antiplatelet therapies in increasing the vascular access patency duration or decreasing the thrombosis of arteriovenous grafts.

Objective

To determine the effect of low dose aspirin and dipyridamole on primary patency of arteriovenous grafts in hemodialysis patients

Methods

This randomized, double-blind, placebo-controlled trial was done at Imam Reza Hospital in Mashhad, Iran from September 10, 2015 to July 05, 2016. Sixty hemodialysis patients, after the placement of a new arteriovenous graft, were divided into three study groups which including; Group 1, who received 80 mg aspirin tablet daily, Group 2 received 80 mg aspirin plus 75 mg dipyridamole daily and Group 3 received placebo daily. Primary unassisted patency was recorded in follow-up until 12 months and the outcomes were analysed using one-way ANOVA test.

Results

Primary patency time in Group 1 (Aspirin) was 324.75±147.00 day and for Group 2 (Aspirin + Dipyridamole) was 399.05±92.09 day and for Group 3 (Placebo) was 383.55±108.23 day. There were no significant differences between the 3 groups (p>0.05). Successful dialysis was done in 16.7% in Group 1, 37.5% in Group 2 and 45% in Group 3 from brachial arteriovenous grafts after 1-year follow-up (p=0.746).

Conclusions

In treating dialysis patients, treatment with low dose aspirin and dipyridamole is not effective on increasing the synthetic grafts primary patency duration.

Trial registration

The trial was registered at the Thai Clinical Trials Registry (http://www.clinicaltrials.in.th) with the Trct id: TCTR20160920003.

Funding

The authors received no financial support for the research, authorship, and/or publication of this article.

Reduction of intracerebral hemorrhage in hemodialysis patients after reducing aspirin use: A quality-assurance observational study

There is so far no international consensus concerning the prescription of antithrombotic agents in hemodialysis patients. It is not clear yet why they cause more bleeding in some patients and are beneficial in others. We therefore tried to find out what triggers bleeding in this population. This is an observational before-and-after study that included all patients undergoing hemodialysis in our center between 2005 and 2015. We divided the study into two phases: phase one (125 patients) where aspirin was used without restrictions and phase two (110 patients) where aspirin was avoided in severe hypertension and primary prevention. We aimed to assess the differential occurrence of intracerebral hemorrhage between the two phases and the cardiovascular mortality of patients whether on aspirin or not. Bleeding events occurred in 12.8% of patients in phase one and 13.6% in phase two (p = 0.85). Seven out of 125 patients (6%) in phase one experienced intracerebral hemorrhage and none in phase two. Intracerebral hemorrhage was significantly increased in those with the combination of aspirin and severe hypertension (p = 0.003). Aspirin and acenocoumadin were significantly associated with total bleeding (OR = 3.81 and 4.85 with p = 0.005 and 0.001 respectively). Cardiovascular mortality did not differ between phase one and two whether patients were on aspirin or not (p = 0.45 and 0.31 respectively). Minimizing aspirin use in hemodialysis patients with severe hypertension reduced intracerebral bleeding without a significant difference in cardiovascular mortality.

Impact of the Number of Anti-Thrombosis Agents in Hemodialysis Patients: BOREAS-HD2 Study

BACKGROUND/AIMS

Relationships between the number of anti-thrombosis agents, clinical benefits and adverse events in hemodialysis (HD) patients are unclear.

METHODS

All patients on HD in 22 institutes (n = 1,071) were enrolled and followed up for 3 years. After exclusion of patients with missing data, kidney transplantation or retraction of consent during the follow-up period (n = 204), mortality rate and ischemic and hemorrhagic events were compared between different regimens of anti-thrombosis agents.

RESULTS

The use of dual or triple antiplatelet (AP) agents (HR:2.03, 95% CI:1.01-4.13, p = 0.04) and the combination of an AP agent and warfarin (WF) (HR:4.84, 95%CI 1.96-11.96, p < 0.001) were associated with an increase in hemorrhagic events compared with no use of anti-thrombosis agents. No anti-thrombosis regimen was associated with a significant change in risk of ischemic stroke. The use of dual or triple AP agents, but not WF, was associated with an increase in cardiovascular mortality (HR:2.48, 95% CI:1.24-4.76, p = 0.01).

CONCLUSION

A significant increase in hemorrhagic events by the use of dual or more AP agents and by co-administration of an AP agent and WF in patients on HD should be considered in planning their anti-thrombosis regimen.

S-shaped versus conventional straight skin incision: Impact on primary functional maturation, stenosis and thrombosis of autogenous radiocephalic arteriovenous fistula: Impact of incision on maturation, stenosis & failure of RCAVF. Study design: Prospective observational comparative

Introduction

The objective of this study is to test the null hypothesis that an S-shaped surgical incision versus conventional (straight) skin incision in the creation of autogenous radiocephalic arteriovenous fistulas (RCAVFs) have no impact on the primary end-point of primary functional maturation and secondary end points of stenosis and thrombosis.

Methods

A prospective observational comparative consecutive study with intention-to-treat on individuals undergoing only radiocephalic arteriovenous fistula (RCAVFs) over a period of 12 months was conducted. Variables on patient's demographics, comorbidities, anesthesia type, mean arterial blood pressure, thrill, laterality, cephalic vein and radial artery diameter were collated. The test of probability was assessed through Chi-Square, Kaplan-Meier survival estimator and Log-Rank analysis.

Results

Total of n = 83 individuals with median age of 67 years (IQR, 20–89) and male predominance 83% during this period were subjected to RCAVF formation. Total of n = 45 patients in straight skin incision were compared to n = 38 individuals in S-shaped group. Despite equal prevalence of demographics, comorbidities, anesthesia type, mean arterial blood pressure (MAP), thrill, laterality, cephalic vein and radial artery diameter (p > 0.05) higher incidence of juxta-anastomotic stenosis was noted in the straight skin incision group (p = 0.029) in comparative and survival analysis (Log-Rank, p = 0.036). The maturation of the entire cohort was 69% (S-shaped 76% vs. straight group 62%) (p > 0.05).

Conclusion

The outcome of this study demonstrates that S-shaped surgical skin incision is associated with a lower incidence of stenosis in comparison to straight incision type in RCAVF formation.

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S-shaped skin incision is an alternative to the conventional skin incision for creation of radiocephalic arteriovenous fistula (RCAVF).

•

This approach permits better exposure for both vessels and minimise the need for extensive mobilisation of cephalic vein.

•

S-shaped skin incision is associated with lower incidence of stenosis within the maturation period.

Different impact of aspirin on renal progression in patients with predialysis advanced chronic kidney disease with or without previous stroke

BACKGROUND

The benefit of reducing the risk of stroke against increasing the risk of renal progression associated with antiplatelet therapy in patients with advanced chronic kidney disease (CKD) is controversial.

METHODS

We enrolled 1301 adult patients with advanced CKD treated with erythropoiesis stimulating agents from January 1, 2002 to June 30, 2009 from the 2005 Longitudinal Health Insurance Database in Taiwan. All of the patients were followed until the development of the primary or secondary endpoints, or the end of the study (December 31, 2011). The primary endpoint was the development of ischemic stroke, and the secondary endpoints included hospitalization for bleeding events, cardiovascular mortality, all-cause mortality, and renal failure. The adjusted cumulative probability of events was calculated using multivariate Cox proportional regression analysis.

RESULTS

Adjusted survival curves showed that the usage of aspirin was not associated with ischemic stroke, hospitalization for bleeding events, cardiovascular mortality or all-cause mortality, however, it was significantly associated with renal failure. In subgroup analysis, aspirin use was associated with renal failure in the patients with no history of stroke (HR, 1.41; 95% CI, 1.14-1.73), and there was a borderline interaction between previous stroke and the use of aspirin on renal failure (interaction p=0.0565).

CONCLUSIONS

There was no significant benefit in preventing ischemic stroke in the patients with advanced CKD who received aspirin therapy. Furthermore, the use of aspirin was associated with the risk of renal failure in the patients with advanced CKD without previous stroke.

Hemodialysis Tunneled Catheter Noninfectious Complications

Noninfectious hemodialysis catheter complications include catheter dysfunction, catheter-related thrombus, and central vein stenosis. The definitions, causes, and treatment strategies for catheter dysfunction are reviewed below. Catheter-related thrombus is a less common but serious complication of catheters, requiring catheter removal and systemic anticoagulation. In addition, the risk factors, clinical manifestation, and treatment options for central vein stenosis are outlined.

Dual Antiplatelet Therapy and Clinical Outcomes after Coronary Drug-Eluting Stent Implantation in Patients on Hemodialysis

BACKGROUND AND OBJECTIVES

We aimed to investigate the benefits and risks of dual antiplatelet therapy (DAPT) after coronary drug-eluting stent (DES) implantation in patients undergoing hemodialysis.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A nested case-control analysis of patients on hemodialysis after receipt of DES and DAPT treatment was conducted using data from Taiwan's National Health Insurance Research Database for the period 2007-2011. Cases of myocardial infarction or death within 1 year after DES implantation were matched one-to-one with control patients. Odds ratios were calculated to compare DAPT continuation with discontinuation. Additionally, a propensity score-adjusted 6-month landmark cohort analysis was also conducted to evaluate the long-term benefits and risks of prolonged (>6 months) compared with ≤6 months of DAPT use. The primary outcomes were death and myocardial infarction. The secondary outcomes were ischemic stroke, revascularization, and major bleeding.

RESULTS

In the nested case-control analysis, patients who continued DAPT had a lower rate of death or myocardial infarction within 1 year after receipt of a DES (adjusted odds ratio, 0.54; 95% confidence interval, 0.36 to 0.81; P=0.003), whereas this association became statistically nonsignificant when compared with patients who discontinued DAPT for the period between 6 and 12 months after receipt of a DES (adjusted odds ratio, 1.51; 95% confidence interval, 0.75 to 3.04). In the propensity score-adjusted cohort analysis, >6 months of DAPT use was not associated with different primary or secondary outcomes than shorter-term use.

CONCLUSIONS

Our findings support that the clinical effectiveness of extended DAPT in a hemodialysis population may be tempered after 6 months post-DES implantation.

Antithrombotic medications in dialysis patients: a double-edged sword

In the clinical context of end-stage renal disease (ESRD), thrombosis and bleeding risks are simultaneously increased and may have devastating consequences. While anticoagulant and antiplatelet drugs are indispensable for the prevention of thromboembolic events, the significantly higher bleeding risk makes their handling extremely complicated. In ESRD, they are frequently administered for a wide array of conditions. For example, atrial fibrillation is quite common in ESRD and warrants the use of anticoagulants like warfarin. Unfractionated heparin and low molecular weight heparins are typically used for clotting prevention in the hemodialysis extracorporeal circuit. The antithrombotics use dilemma has worsened because ESRD patients have been excluded from major clinical trials that defined standard indications, contraindications and optimal management of these medications. That limits our knowledge and results in that the process of decision-making depends on weaker data. Besides the substantial bleeding risk, warfarin may also increase cardiovascular risk because it is implicated in the pathogenesis of vascular calcifications in ESRD. The present article attempts to offer a comprehensive overview of practical considerations for the use of the most common antithrombotic medications in ESRD linking them, at the same time, to the best available evidence from randomized controlled trials and observational studies.

Antiplatelet agents in hemodialysis

Patients affected by cardiovascular disease (CVD) are treated with antiplatelet agents (AA) and/or anticoagulant drugs, which are fundamental in the management of stroke, coronary atherosclerotic disease, peripheral vascular disease and atrial fibrillation. CVD is the most important cause of death in chronic renal failure (CRF). Death rates from myocardial infarction (MI) and from all other cardiac causes exceed those for the general population. Incidence of MI in CRF is triple that in the general population. Moreover, mortality is seven- to eight-fold higher in patients requiring chronic hemodialysis compared to the general population, and approximately 40% of deaths in this population are attributable to coronary artery disease (CAD). For these reasons, AA are widely used in patients affected by CRF. Current data do not support a protective effect of antiplatelet administration in hemodialytic patients as primary prevention of cardiovascular mortality. Different results have been obtained concerning secondary prevention of CVD. The Cooperative Cardiovascular Project demonstrated that dialysis patients treated with aspirin following MI had a 43% lower mortality. Another study reported that the use of aspirin and beta-blockers following MI was associated with lower mortality in CRF patients. However, aspirin plus clopidogrel seems to increase the hemorrhagic risk without a significant reduction in cardiovascular mortality and there are insufficient data to support the use of new AA drugs in hemodialytic patients. In conclusion, since CRF patients are one of the groups at highest risk for atherosclerotic events, it could be reasonable to use aspirin in HD patients. However, the bleeding risk in HD patients needs to be strongly evaluated, especially before starting dual AA treatment.

Role of Cilostazol Therapy in Hemodialysis Patients with Asymptomatic Peripheral Arterial Disease: A Retrospective Cohort Study

Background. Peripheral arterial disease (PAD) and its relevant complications are more common in hemodialysis (HD) patients, while the evidence regarding antiplatelet therapy in CKD patients is scarce. We retrospectively analyzed the efficacy of cilostazol on outcomes in HD patients with asymptomatic PAD (aPAD). Methods. This cohort study enrolled 217 HD patients (median follow-up time: 5.75 years). Associations between cilostazol use and the outcomes were evaluated by time-dependent Cox regression analysis. Results. During follow-up, 39.5% (47/119) patients used cilostazol for aPAD and 31.8% (69/217) patients died. Cilostazol users had significantly lower CVD and all-cause mortalities (adjusted HR [95% CI]: 0.11 [0.03, 0.51] and 0.2 [0.08, 0.52]) than nonusers. Both death risks were nonsignificantly higher in cilostazol users than in HD patients without aPAD. The unadjusted and adjusted HR [95% CI] of CVD death risk were 0.4 [0.07, 2.12] and 0.14 [0.02, 0.8] for patients with aPAD during follow-up and were 0.74 [0.16, 3.36] and 0.19 [0.04, 0.93] for those with aPAD at initial. Conclusions. In HD patients with aPAD, lower CVD and all-cause mortality rates were observed in low-dose cilostazol user. Further evidences from large-scale prospective study and randomization trial are desired to confirm the effect of cilostazol.

Hemodialysis Tunneled Catheter Noninfectious Complications

Noninfectious hemodialysis catheter complications include catheter dysfunction, catheter-related thrombus, and central vein stenosis. The definitions, causes, and treatment strategies for catheter dysfunction are reviewed below. Catheter-related thrombus is a less common but serious complication of catheters, requiring catheter removal and systemic anticoagulation. In addition, the risk factors, clinical manifestation, and treatment options for central vein stenosis are outlined.

Should patients be on antithrombotic medication for their first arteriovenous fistulae?

PURPOSE

Evidence on the effect of antithrombotic medication on reducing early and late fistula failure is inconclusive. Antithrombotic use carries risks in patients with end-stage renal failure and could increase the risk of needling complications as a result of bleeding. The objectives of this study are to determine the effect of antithrombotic agents on early and late fistula failure and on the risk of interrupted start of cannulation of the fistula.

METHODS

Retrospective analysis of two prospectively maintained databases of access operations and dialysis sessions of 671 patients who had their first fistula between 2004 and 2011. Early failure was defined as failure to reach six consecutive dialysis sessions at any time with two needles on the index form of access. Fistula survival was defined as the time from when the fistula was first used to fistula abandonment.

RESULTS

Primary failure was similar between patients on antiplatelet (18.8%), anticoagulants (18.4%) or no antithrombotic medication (18.8%; p = 0.998). Antithrombotic medication did not have an effect on AVF survival (p = 0.86). Antithrombotic medication did not increase complicated cannulation rates, defined as the percentage of patients failing to achieve six uninterrupted dialysis sessions from the start (p = 0.929).

CONCLUSIONS

Antithrombotic medication had no significant effect on primary failure rate, long-term fistula survival or initial complicated cannulation rates in our study. This suggests that patients already on antithrombotic medication can continue taking them without increasing the risk of interrupted dialysis.

Anticoagulation in Chronic Hemodialysis: Progress Toward an Optimal Approach

Appropriate anticoagulation for hemodialysis (HD) requires a subtle balance between under- and over-heparinization to prevent extracorporeal circuit (ECC) clotting and bleeding, respectively. We discuss five key issues relating to anticoagulation therapy for chronic HD in adults following a review of relevant literature published since 2002: (i) options for standardization of anticoagulation in HD settings. The major nephrology societies have issued low evidence level recommendations on this subject. Interventional studies have generally investigated novel low-molecular weight heparins and provided data on safety of dosing regimens that cannot readily be extrapolated to clinical practice; (ii) identification of clinical and biological parameters to aid individualization of anticoagulation treatment. We find that use of clinical and biological monitoring of anticoagulation during HD sessions is currently not clearly defined in routine clinical practice; (iii) role of ECC elements (dialysis membrane and blood lines), dialysis modalities, and blood flow in clotting development; (iv) options to reduce or suppress systemic heparinization during HD sessions. Alternative strategies have been investigated, especially when the routine mode of anticoagulation was not suitable in patients at high risk of bleeding or was contraindicated; (v) optimization of anticoagulation therapy for the individual patient. We conclude by proposing a standardized approach to deliver anticoagulation treatment for HD based on an individualized prescription prepared according to the patient's profile and needs.

Effectiveness of and risk associated with aspirin therapy in hemodialysis patients with a background of antiplatelet factor 4/heparin complex antibody detection

BACKGROUND

The optimal prevention measures against hemodialysis (HD)-associated complications, including all-cause thrombotic events and death, are unclear.

METHODS

This prospective study was designed to assess the effect of aspirin on prevention of HD-associated complications. Patients were divided into four groups according to platelet factor-4/heparin-complex (PF4/H) antibody detection and aspirin prescription: Group 1, antibody(-)/aspirin(+); Group 2, antibody(-)/aspirin(-); Group 3, antibody(+)/aspirin(+); and Group 4, antibody(+)/aspirin(-). Adverse events were compared among all four groups. Cox hazard regression was performed to analyze the effects of anti-PF4/H antibody and aspirin on thrombosis and death.

RESULTS

This study included 648 patients undergoing HD; 142 were positive for anti-PF4/H antibodies, and 229 had received aspirin before enrollment. During the 4-year follow-up period, 138 patients developed thrombosis, and 63 of these events were anti-PF4/H antibody-associated. A total of 112 patients died; 75 died of coronary heart disease (CHD). Group 4 had a significantly higher incidence of total and anti-PF4/H antibody-associated thrombosis events as well as total and CHD-associated death than did the other three groups. Aspirin had a preventive effect against all adverse events in anti-PF4/H antibody-positive patients, but not in antibody-negative patients. Group 1 patients with baseline D-dimer levels of <0.6μg/mL developed more hemorrhagic events than did patients in the other groups.

CONCLUSIONS

Aspirin prevention of thrombosis and death in patients undergoing HD might require consideration of the anti-PF4/H antibody status. In antibody-positive individuals, taking aspirin could improve the prognosis and therefore might be recommended. In antibody-negative individuals, prevention was minimal and the bleeding risk was obviously increased; thus, aspirin should be avoided or at least require careful evaluation prior to aspirin treatment.

The three-year incidence of major hemorrhage among older adults initiating chronic dialysis

Background

For those who initiate chronic dialysis, knowing what proportion will experience 3-year outcomes of hemorrhage with hospitalization informs patient prognosis, disease impact, and the planning of trials and programs to prevent events.

Objectives

We examined the incidence of hemorrhage and related gastrointestinal endoscopic procedures in incident older dialysis patients and stratified patients by age, era, dialysis modality and whether recently prescribed anti-thrombotic medication.

Design

Retrospective cohort study

Setting

Ontario, Canada from 1998 to 2008 (n = 11,173)

Patients

All older patients (>65 years) who initiated chronic dialysis

Measurements

Hospitalization with hemorrhage and its subtypes (upper and lower gastrointestinal, intra-cerebral, subarachnoid) and related-gastrointestinal procedures.

Methods

Three-year outcomes of hospitalization with hemorrhage were expressed as cumulative incidence and incidence rate (number of events per 1,000 patient years). Results were stratified by patient age (66 to 74, 75 to 84, ≥ 85), era (1998 to 2001, 2002 to 2005, 2006 to 2008) and dialysis modality. Among those with hemorrhage, we examined prescriptions for anti-thrombotic medications (warfarin, clopidogrel) in the preceding 120 days.

Results

The 3-year cumulative incidence of hemorrhage was 14.4% (roughly 1 in 7 patients). By location, the 3-year cumulative incidence was 8.9% lower gastrointestinal, 6.1% upper gastrointestinal, 0.9% intra-cerebral and 0.1% sub arachnoid hemorrhage. The 3-year cumulative incidence of gastrointestinal endoscopic procedures was 14.8%. The cumulative incidence and rate of hemorrhage were not appreciably different across the 3 age strata, by era or by dialysis modality. Among patients with a hemorrhage, 29.5% were prescribed warfarin in the preceding 120 days, and 8.4% clopidogrel.

Limitations

Recurrent events were not included.

Conclusions

Many older patients who initiate chronic dialysis will be hospitalized with hemorrhage and receive related procedures over the subsequent three years. Despite greater age and co-morbidity over the last decade this incidence has not changed.

Electronic supplementary material

The online version of this article (doi:10.1186/s40697-014-0021-x) contains supplementary material, which is available to authorized users.

Anticoagulant and antiplatelet therapy in patients with chronic kidney disease: risks versus benefits review

PURPOSE OF REVIEW

Atrial fibrillation and cardiovascular death are increased in end-stage renal disease (ESRD) patients compared to the general population. The effect of anticoagulant and antiplatelet medications for these indications in ESRD is unclear. However, both classes of medications have been used for the preservation of vascular access. This review explores the risks and benefits of anticoagulant and antiplatelet medications in ESRD.

RECENT FINDINGS

ESRD patients with atrial fibrillation have a two and three-fold greater risk of death and stroke, respectively, than ESRD patients without atrial fibrillation. Warfarin does not appear to decrease this risk, and increases the risk of bleeding and vascular calcification. Warfarin also does not appear to be effective for vascular access preservation. In a few large observational studies, antiplatelet agents did not decrease the risk of cardiovascular death, but confounding by indication is likely. Antiplatelet agents do appear to prolong unassisted arteriovenous graft patency, but the effect is modest.

SUMMARY

The role of anticoagulant and antiplatelet agents for atrial fibrillation and cardiovascular disease in ESRD remains unclear. Well designed randomized controlled trials to determine the role of anticoagulation in ESRD patients with atrial fibrillation, and anticoagulant and antiplatelet medications in the preservation of central venous catheter function are required.

Impaired thrombolysis: a novel cardiovascular risk factor in end-stage renal disease

AIMS

End-stage renal disease (ESRD) patients have an excess cardiovascular risk, above that predicted by traditional risk factor models. Prothrombotic status may contribute to this increased risk. Global thrombotic status assessment, including measurement of occlusion time (OT) and thrombolytic status, may identify vulnerable patients. Our aim was to assess overall thrombotic status in ESRD and relate this to cardiovascular risk.

METHODS AND RESULTS

Thrombotic and thrombolytic status of ESRD patients (n = 216) on haemodialysis was assessed using the Global Thrombosis Test. This novel, near-patient test measures the time required to form (OT) and time required to lyse (lysis time, LT) an occlusive platelet thrombus. Patients were followed-up for 276 ± 166 days for major adverse cardiovascular events (MACE, composite of cardiovascular death, non-fatal MI, or stroke). Peripheral arterial or arterio-venous fistula thrombosis was a secondary endpoint. Occlusion time was reduced (491 ± 177 vs. 378 ± 96 s, P < 0.001) and endogenous thrombolysis was impaired (LT median 1820 vs.1053 s, P < 0.001) in ESRD compared with normal subjects. LT ≥ 3000 s occurred in 42% of ESRD patients, and none of the controls. Impaired endogenous thrombolysis (LT ≥ 3000 s) was strongly associated MACE (HR = 4.25, 95% CI = 1.58-11.46, P = 0.004), non-fatal MI and stroke (HR = 14.28, 95% CI = 1.86-109.90, P = 0.01), and peripheral thrombosis (HR = 9.08, 95% CI = 2.08-39.75, P = 0.003). No association was found between OT and MACE.

CONCLUSION

Impaired endogenous thrombolysis is a novel risk factor in ESRD, strongly associated with cardiovascular events.

Dialysis search filters for PubMed, Ovid MEDLINE, and Embase databases

BACKGROUND AND OBJECTIVES

Physicians frequently search bibliographic databases, such as MEDLINE via PubMed, for best evidence for patient care. The objective of this study was to develop and test search filters to help physicians efficiently retrieve literature related to dialysis (hemodialysis or peritoneal dialysis) from all other articles indexed in PubMed, Ovid MEDLINE, and Embase.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A diagnostic test assessment framework was used to develop and test robust dialysis filters. The reference standard was a manual review of the full texts of 22,992 articles from 39 journals to determine whether each article contained dialysis information. Next, 1,623,728 unique search filters were developed, and their ability to retrieve relevant articles was evaluated.

RESULTS

The high-performance dialysis filters consisted of up to 65 search terms in combination. These terms included the words "dialy" (truncated), "uremic," "catheters," and "renal transplant wait list." These filters reached peak sensitivities of 98.6% and specificities of 98.5%. The filters' performance remained robust in an independent validation subset of articles.

CONCLUSIONS

These empirically derived and validated high-performance search filters should enable physicians to effectively retrieve dialysis information from PubMed, Ovid MEDLINE, and Embase.

Colorectal complications of end-stage renal failure and renal transplantation: a review

AIM

End-stage renal failure (ESRF) and renal transplant recipients are thought to be associated with an increased risk of colorectal complications.

METHOD

A review of the literature was performed to assess the prevalence and outcome in both benign and malignant colorectal disease.

RESULTS

No prospective randomized studies assessing colorectal complications in ESRF or renal transplant were identified. Case series and case reports have described the incidence and management of benign colorectal complications. Complications included diverticulitis,infective colitis, colonic bleeding and colonic perforation. There was insufficient evidence to associated iverticular disease with adult polycystic kidney disease.Three population-based studies have shown up to a twofold increased incidence of colonic cancer but not rectal cancer for renal transplant recipients. Bowel cancer screening (as per the general population) by faecal occult blood testing appears justified for renal transplant patients; however, evidence suggests that consideration of starting screening at a younger age may be worthwhile because of an increased risk of developing colonic cancer.Two population-based studies have shown a threefold and 10-fold increased incidence of anal cancer for renal transplant recipients. A single case–control study demonstrated significant increased prevalence of anal human papilloma virus (HPV) and intraepithelial neoplasia (AIN)in patients with established renal transplants.

CONCLUSIONS

Despite the lack of high-level evidence,ESRF and renal transplantation were associated with colorectal complications that could result in major morbidity and mortality. Bowel cancer screening in this patient group appears justified. The effectiveness of screening for HPV, AIN and anal cancer in renal transplant recipients remains unclear.

Cardiac catheterization in the dialysis population in 2012: we know more, but much remains unknown

Chronic kidney disease is now widely accepted as an independent risk factor for coronary disease and the dialysis population may represent the highest risk subgroup. Among all dialysis patients, a cardiac cause of mortality has been estimated at 40%. In addition, prior studies have demonstrated that when cardiac catheterization is obtained in a consecutive series of asymptomatic diabetic patients on dialysis the rates of coronary disease can approach 50%. However, the ability to define the problem continues to be greater than the ability to treat or prevent it. Coronary revascularization strategies have limitations in the general population which are amplified in the dialysis population. The ability to accurately diagnose an acute coronary syndrome is more difficult, clinical outcomes have a smaller margin of benefit, and technical challenges result in higher complication rates. Recent data demonstrate an inverse relationship between glomerular filtration rate and the risk of presenting with an acute myocardial infarction rather than unstable angina suggesting that patients with CKD may have a unique pathophysiologic profile that is more prone to plaque rupture. However, these "vulnerable" plaques typically are associated with stenoses <50% prior to rupture and are thus poor targets for revascularization and perhaps best treated with medical therapy. Although the benefits of revascularization may continue to outweigh the risks in the context of acute coronary syndromes, preventive strategies would have to overcome the lower margin of benefit and higher complication rates.

Bilateral spontaneous perirenal hemorrhage in an acquired cystic kidney disease hemodialysis patient

Acquired cystic kidney disease (ACKD) is a well-known late stage complication of chronic kidney disease. Cysts tend to grow with time on dialysis and could lead to malignant transformation, and intra- or perirenal hemorrhage is a rare complication of ACKD. Here we describe one case of bilateral spontaneous perirenal hemorrhage of ACKD in a 44-year-old man, on hemodialysis for 15 years. One was due to cyst rupture, and the other was due to aneurism rupture, both were controlled with transcatheter arterial embolization. In renal arteriography at the second rupture, we demonstrated extravasation from an aneurysm being present at the periphery of right renal artery. Several spontaneous perirenal hemorrhage cases were reported but its clinical information is limited, moreover, bilateral cases were extremely rare. Furthermore, to our knowledge, this is the first report of spontaneous perirenal hemorrhage caused by intraparenchymal renal artery aneurysm rupture in ACKD patients. We report this case because of its rarity and significance with respect to the complication of dialysis patients, review reported bilateral cases, and discuss some clinical characteristics.