Effectiveness and Safety of Antiplatelet in Stroke Patients with End-Stage Renal Disease Undergoing Dialysis

Factors associated with readmission in chronic kidney disease: Systematic review and meta-analysis

BACKGROUND

Risk factors associated with all-cause hospital readmission are poorly characterised in patients with chronic kidney disease.

OBJECTIVE

A systematic review and meta-analysis were conducted to identify risk factors and protectors of hospital readmission in chronic kidney disease.

DESIGN, PARTICIPANTS & MEASUREMENTS

Studies involving adult patients were identified from four databases from inception to 31/03/2020. Random-effects meta-analyses were conducted to determine factors associated with all-cause 30-day hospital readmission in general chronic kidney disease, in dialysis and in kidney transplant recipient groups.

RESULTS

Eighty relevant studies (chronic kidney disease, n = 14 studies; dialysis, n = 34 studies; and transplant, n = 32 studies) were identified. Meta-analysis revealed that in both chronic kidney disease and transplant groups, increasing age in years and days spent at the hospital during the initial stay were associated with a higher risk of 30-day readmission. Other risk factors identified included increasing body mass index (kg/m2 ) in the transplant group, and functional impairment and discharge destination in the dialysis group. Within the chronic kidney disease ​​​​group, having an outpatient follow-up appointment with a nephrologist within 14 days of discharge was protective against readmission but this was not protective if provided by a primary care provider or a cardiologist.

CONCLUSION

Risk-reduction interventions that can be implemented include a nephrologist appointment within 14 days of hospital discharge, rehabilitation programme for functional improvement in the dialysis group and meal plans in the transplant group. Future risk analysis should focus on modifiable factors to ensure that strategies can be tested and implemented in those who are more at risk.

Controversies: Stroke Prevention in Chronic Kidney Disease

Risk of both ischemic and hemorrhagic stroke is increased in the chronic kidney disease (CKD) population, particularly in end-stage kidney disease patients. Uremic factors that contribute to stroke risk include blood pressure variability, vascular calcification, build-up of vascular toxins, chronic inflammation, platelet dysfunction and increased brain microbleeds. This paper discusses the controversial evidence for stroke prevention strategies including blood pressure control, statins, antiplatelet agents, and anticoagulation in the CKD population. Only a few randomized clinical trials included patients with advanced CKD, thus evidence is derived mostly from observational cohorts and real-world data. Overall, targeting a lower systolic blood pressure below 120 mmHg and statin prescription do not appear to decrease stroke risk in CKD. Antiplatelet agents have not shown a clear benefit for secondary stroke prevention, but aspirin may reduce incident stroke in hypertensive CKD stage 3B-5 patients. Observational data suggests that the factor Xa inhibitor apixaban has a favorable profile over warfarin in dialysis patients with atrial fibrillation; apixaban being associated with lower stroke risk and fewer major bleeding events.

Anticoagulation in Patients with End-Stage Renal Disease and Atrial Fibrillation: Confusion, Concerns and Consequences

End-stage renal disease (ESRD) patients have a higher prevalence of diabetes mellitus, hypertension, congestive heart failure and advanced age, along with an increased incidence of non-valvular atrial fibrillation (AF), thereby increasing the risk for cerebrovascular accidents. Systemic anticoagulation is therefore recommended in patients with ESRD with AF to reduce the risk and complications from thromboembolism. Paradoxically, these patients are at an increased risk of bleeding due to great degree of platelet dysfunction and impaired interaction between platelet and endothelium. Currently, CHA2DS2-VASc and Hypertension, Abnormal liver/kidney function, Stroke, Bleeding, Labile INR, Elderly, Drugs or alcohol (HAS-BLED) are the recommended models for stroke risk stratification and bleeding risk assessment in patients with AF. There is conflicting data regarding benefits and risks of medications such as antiplatelet agents, warfarin and direct oral anticoagulants in ESRD patients with AF. Moreover, there is no randomized controlled trial data to guide the clinical decision making. Hence, a multi-disciplinary approach with annual re-evaluation of treatment goals and risk-benefit assessment has been recommended. In this article, we review the current recommendations with risks and benefits of anticoagulation in patients with ESRD with AF.

Efficacy of Antiplatelet Agent Usage for Primary and Secondary Prevention in Dialysis Patients: a Nationwide Data Survey and Propensity Analysis

BACKGROUND

Although cardiovascular (CV) disease is the leading cause of mortality and morbidity in dialysis patients, there is little evidence to guide the use of antiplatelet agents in dialysis patients.

METHOD

A nationwide database (Registry for Catastrophic Illnesses) for Taiwan, which has data from nearly all patients who received dialysis therapy from 1995 to 2008, was used. This is a population-based cohort study with time to event analyses to estimate the relation between antiplatelet agent use and outcomes. Hazard ratios were calculated to evaluate the effect of antiplatelet agent use on the risk of major CV events and mortality. Baseline characteristics were matched by propensity score (PS).

RESULTS

A total of 71,835 were included, and 10,595 (14.7%) patients received an anti-platelet agent. The median value of follow-up days was 61.6 months. After PS-based matching, 9598 patients who used an antiplatelet agent and 23,794 non-users were included in the analysis. After PS matching, there was no difference between patients using an antiplatelet agent or not in CV events (p = 0.672) and total mortality (p = 0.529). A subgroup analysis of different usage periods of antiplatelet agents indicated that CV events and total mortality were similar in those who used antiplatelet agents for short or long durations. In subgroup analysis, there was also no difference between patients with a different modality of dialysis (hemodialysis or peritoneal dialysis), different antiplatelet agents (aspirin, clopidogrel, and/or ticlopidine) or patients with/without previous cardiovascular disease in CV events and total mortality.

CONCLUSIONS

Antiplatelet agent usage does not reduce CV events and total mortality in dialysis patients.

Pros and cons of antithrombotic therapy in end-stage kidney disease: a 2019 update

Dialysis patients manifest both an increased thrombotic risk and a haemorrhagic tendency. A great number of patients with chronic kidney disease requiring dialysis have cardiovascular comorbidities (coronary artery disease, atrial fibrillation or venous thromboembolism) and different indications for treatment with antithrombotics (primary or secondary prevention). Unfortunately, few randomized controlled trials deal with antiplatelet and/or anticoagulant therapy in dialysis. Therefore cardiology and nephrology guidelines offer ambiguous recommendations and often exclude or ignore these patients. In our opinion, there is a need for an expert consensus that provides physicians with useful information to make correct decisions in different situations requiring antithrombotics. Herein the European Dialysis Working Group presents up-to-date evidence about the topic and encourages practitioners to choose among alternatives in order to limit bleeding and minimize atherothrombotic and cardioembolic risks. In the absence of clear evidence, these clinical settings and consequent therapeutic strategies will be discussed by highlighting data from observational studies for and against the use of antiplatelet and anticoagulant drugs alone or in combination. Until new studies shed light on unclear clinical situations, one should keep in mind that the objective of treatment is to minimize thrombotic risk while reducing bleeding events.

The Use of Aspirin to Reduce the Risk of Thrombotic Events in Patients With End-Stage Renal Disease: Protocol for a Randomized Controlled Trial

Background

End-stage renal disease (ESRD) is the last stage of chronic kidney disease, mainly caused by type 2 diabetes mellitus and characterized by an increased mortality risk related to cardiovascular disease. Low-dose aspirin (acetylsalicylic acid or ASA) seems to effectively prevent cardiovascular events in patients with ESRD. However, the number of interventional studies in this population remains limited and the mechanisms of aspirin-related bleeding remain poorly understood. Aspirin’s efficacy and safety may be modified by the presence of type 2 diabetes mellitus or platelet hyperreactivity.

Objective

The overall objective of this protocol is to (1) evaluate aspirin’s safety and efficacy in reducing the risk of thrombotic events in patients with ESRD on hemodialysis and (2) examine whether aspirin’s efficacy is modified by the presence of type 2 diabetes mellitus or platelet hyperreactivity. Specifically, the primary objective is to compare the 12-month rate of any thrombotic event (cardiac death, nonfatal myocardial infarction, nonfatal stroke, arteriovenous fistula thrombosis) and Thrombolysis in Myocardial Infarction (TIMI) major bleeding in patients treated with aspirin compared to those on placebo. Secondary objectives are to test for effect modification of treatment by the presence of type 2 diabetes mellitus or platelet hyperreactivity and compare the rate of TIMI minor bleeding between treatment groups.

Methods

We developed a protocol for a phase 2 randomized, single-center, placebo-controlled, triple-blind, superiority clinical trial to assess the prophylactic efficacy and safety of aspirin in patients with ESRD and on hemodialysis. It follows the ethical principles of the Declaration of Helsinki of the World Medical Association. A total of 342 participants would be enrolled over 12 months at a large dialysis center. Patients will be randomized in a 1:1 ratio and stratified by presence of type 2 diabetes mellitus and platelet hyperreactivity to receive either oral aspirin (100 mg/d) or placebo for a treatment period of 12 months. An intention-to-treat statistical analysis will be performed.

Results

The randomized clinical trial will be performed after approval by the ethical committee of the participating center and registration at ClinicalTrials.gov.

Conclusions

We provide a protocol for a randomized controlled trial to evaluate the safety and efficacy of treatment with aspirin to reduce the risk of thrombotic events. In addition, such a study would further our understanding of the mechanism of aspirin-related bleeding and help identify subgroups of best-responders and patients with a higher risk of adverse events.

Registered Report Identifier

RR1-10.2196/10516

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.

Association of Paroxysmal Supraventricular Tachycardia with Ischemic Stroke: A National Case-Control Study

BACKGROUND AND PURPOSE

Cardioembolic stroke accounts for approximately 15%-20% of all ischemic strokes. Atrial fibrillation constitutes one-half to two-thirds of all cardioembolic stroke events. The association of paroxysmal supraventricular tachycardia (PSVT) with ischemic stroke remains unclear. A national case-control study was conducted to identify the risk factors, including PSVT, for ischemic stroke in Taiwan.

METHODS

We designed a national case-control study comprising patients diagnosed with ischemic stroke (n = 5633) from 1997 to 2011; each patient from the case group was randomly matched with the control group (n = 30,895) in Taiwan. Data were retrospectively collected from Taiwan's National Health Insurance Research Database, which contains not only claims data on hospitalization, emergency room visits, and outpatient department visits, but also patient characteristics.

RESULTS

Logistic regression analysis was used to identify the risk factors for ischemic stroke. Independent risk factors for ischemic stroke included age (in 5-year intervals; odds ratio [OR], 1.76; 95% confidence interval [CI], 173-1.78), the male sex (versus the female sex; OR, 1.88; 95% CI, 1.74-2.01), chronic kidney disease (OR, 3.09; 95% CI, 2.67-3.57), PSVT (OR, 2.05; 95% CI, 1.30-3.19), and aspirin use (OR, .04; 95% CI, .03-0.05).

CONCLUSIONS

Our study is the first in Taiwan to identify PSVT as a significant risk factor for ischemic stroke. New antithrombotic regimens, including aspirin, can be recommended for the primary prevention of stroke and for reducing the burden of stroke for patients with PSVT.

Effect of Estimated Glomerular Filtration Rate Decline on the Efficacy and Safety of Clopidogrel With Aspirin in Minor Stroke or Transient Ischemic Attack

Background and Purpose—

Patients with chronic kidney disease (CKD) are at a particularly high risk for ischemic and bleeding events. Limited data exist as to the efficacy and safety of clopidogrel in stroke patients with renal dysfunction. Therefore, we sought to assess the impact of decreased kidney function on clinical outcomes for stroke patients on clopidogrel–aspirin treatment.

Methods—

Patients in the CHANCE trial (Clopidogrel in High-Risk Patients With Acute Nondisabling Cerebrovascular Events) were randomized to clopidogrel–aspirin or aspirin-alone treatment. The primary efficacy outcome was new stroke during 90 days, whereas bleeding was the safety outcome. Patients were stratified according to estimated glomerular filtration rate.

Results—

Dual clopidogrel–aspirin therapy was associated with a marked reduction in new strokes compared with the therapy of aspirin alone in patients with normal renal function (hazard ratio, 0.77; 95% confidence interval, 0.60–0.98; P =0.02) and mild CKD (hazard ratio, 0.60; 95% confidence interval, 0.45–0.79; P <0.01), whereas in patients with moderate CKD, no significant benefit from clopidogrel therapy was detected (hazard ratio, 1.00; 95% confidence interval, 0.43–2.35; P =0.99). There was no clear difference in bleeding episodes by treatment assignment across categories of renal impairment.

Conclusions—

Clopidogrel plus aspirin could decrease new stroke in patients with normal kidney function and mild CKD, but no extra benefit was observed in those with moderate CKD. Bleeding risk from the dual therapy did not seem to increase in mild or moderate CKD patients.

Clinical Trial Registration—

URL: http://www.clinicaltrials.gov . Unique identifier: NCT00979589.

Determinants of thromboxane biosynthesis in patients with moderate to severe chronic kidney disease

BACKGROUND

Mechanisms of accelerated atherothrombosis in patients with chronic kidney disease (CKD) are only partly characterized. The aims of this study were to evaluate the extent of thromboxane (TX)-dependent platelet activation in patients with CKD, and to characterize the determinants of altered TX biosynthesis in this setting, with particular reference to enhanced lipid peroxidation, low grade inflammation and CKD-related anemia.

PATIENTS AND METHODS

A cross sectional comparison between urinary 8-iso-PGF2α and 11-dehydro-TXB2, in vivo markers of oxidative stress and platelet activation, respectively, was performed in 115 patients with stage 1-4 CKD.

RESULTS

Levels of both urinary 11-dehydro-TXB2 and 8-iso-PGF2α increased sequentially across the four CKD stages (P<0.0001, Kruskal-Wallis test). Both urinary prostanoids were inversely associated with either estimated glomerular filtration rate (eGFR, P<0.0001) or hemoglobin levels (P<0.0001). A significant direct correlation was also observed between urinary 11-dehydro-TXB2 and 8-iso-PGF2α (Rho=0.620, P<0.0001). On multivariate analysis, urinary 8-iso-PGF2α (β=0.459, P<0.0001), hemoglobin levels (β=- 0.261, P=0.002) and eGFR (β=-0.172, P=0.032) were independent predictors of urinary 11-dehydro-TXB2 (adjusted R(2)=0.488).

CONCLUSIONS

This study provides biochemical evidence of persistent platelet activation in patients with CKD. This condition occurs early in the natural history of the disease and is related to kidney function and oxidative stress. Moreover, we found an independent inverse relationship between hemoglobin levels and TX-dependent platelet activation. This finding may provide a mechanistic link between CKD-related anemia and increased cardiovascular risk.

Low-dose aspirin for prevention of cardiovascular disease in patients on hemodialysis: A 5-y prospective cohort study

Introduction Aspirin is an effective antiplatelet drug for preventing cardiovascular events in high-risk subjects. However, for patients with chronic kidney disease and undergoing hemodialysis (HD), its preventive efficacy remains controversial. The present study aimed to determine whether aspirin therapy reduces the risk of cardiovascular disease (CVD) and all-cause mortality in patients on HD. Methods We conducted a 5-y prospective cohort study involving patients on HD. Major exposure variables included prescription of aspirin (100 mg/d) and no aspirin (nonaspirin). The primary outcomes included all-cause death, cardiovascular events, hemorrhage, and ischemic stroke. The secondary outcome included bleeding events defined by the requirement of hospitalization. Findings In this study, 406 patients on regular HD were involved during a 5-y follow-up. Among these, 152 and 254 propensity-matched patients were enrolled in the aspirin and nonaspirin cohort, respectively. The cumulative survival rate was not significantly higher in the aspirin than in the nonaspirin users (log rank χ²  = 1.080, P = 0.299). Aspirin use was not significantly associated with reduced all-cause mortality, fatal and nonfatal congestive heart failure, as well as acute myocardial infarction and ischemic stroke. The risk of fatal cerebral hemorrhage was not significantly increased in the aspirin users (HR = 1.795, 95% CI 0.666-4.841, P = 0.174). After adjustment for other confounders, aspirin use was also not associated with decreased risk of all-cause mortality and CVD. Discussion The present prospective cohort study suggests that low-dose aspirin use is not associated with a significant decrease in the risks of all-cause mortality, CVD, and stroke in population undergoing HD (ClinicalTrials.gov number, NCT02261025).

A comparison of stroke severity proxy measures for claims data research: a population-based cohort study

PURPOSE

Confounding by disease severity has been viewed as an intractable problem in claims-based studies. A novel 7-variable stroke severity index (SSI) was designed for estimating stroke severity by using claims data. This study compared the performance of mortality models with various proxy measures of stroke severity, including the SSI, in patients hospitalized for acute ischemic stroke (AIS).

METHODS

Data from the Taiwan National Health Insurance Research Database (NHIRD) were analyzed. Three proxy measures of stroke severity were evaluated: Measure 1, the SSI; Measure 2, intensive care unit admission and length of stay; and Measure 3, surgical operation, mechanical ventilation, hemiplegia or hemiparesis, and residual neurological deficits. We performed logistic regression by including age, sex, vascular risk factors, Charlson comorbidity index, and one of the proxy measures as covariates to predict 30-day and 1-year mortality after AIS. Model discrimination was evaluated using the area under the receiver-operating characteristic curve (AUC).

RESULTS

We identified 7551 adult patients with AIS. Models using the SSI (Measure 1) outperformed models using the other proxy measures in predicting 30-day mortality (AUC 0.892 vs 0.851, p < 0.001 for Measure 2; 0.892 vs 0.853, p < 0.001 for Measure 3) and 1-year mortality (AUC 0.816 vs 0.784, p < 0.001 for Measure 2; 0.816 vs 0.782, p < 0.001 for Measure 3).

CONCLUSIONS

Using the SSI facilitated risk adjustment for stroke severity in mortality models for patients with AIS. The SSI is a viable methodological tool for stroke outcome studies using the NHIRD.

Reduced Stroke Risk After Parathyroidectomy in End-Stage Renal Disease: A 13-Year Population-Based Cohort Study

Research information on the risk of stroke in patients with dialysis-dependent end-stage renal disease (ESRD) who have undergone parathyroidectomy (PTX) is scant. We used a nationwide health insurance claims database to select all patients with dialysis-dependent ESRD age 18 years and older for the study population. Of the patients with ESRD, we selected 1083 patients who had undergone PTX between 1998 and 2006 as the PTX group and frequency-matched 1083 patients with ESRD by sex, age, years since the disease diagnosis, and the year of undergoing PTX as the non-PTX group. We used a multivariate Cox proportional hazards regression analysis to measure the risk of stroke for the PTX group compared with the non-PTX group after adjusting for sex, age, premium-based income, urbanization, and comorbidity. The mean follow-up periods were 6.08 and 5.38 years for the PTX and non-PTX groups, respectively. After adjusting for previously mentioned variables, significant risk reductions of stroke (adjusted hazard ratio = 0.57, 95% confidence interval = 0.41-0.79), particularly those of hemorrhagic stroke (adjusted hazard ratio = 0.34, 95% confidence interval = 0.20-0.57), with PTX were observed. Chronologically, the risk of stroke in the PTX group decreased in the second year after PTX and persisted for >3 years. PTX reduces the risk of stroke, particularly that of hemorrhagic stroke, in patients with dialysis-dependent ESRD. Other factors for risk reduction include sex (females), an age <65 years, and the presence of comorbidity.