Ischaemic stroke in incident dialysis patients

Stroke and its correlates among patients on maintenance hemodialysis in Cameroon

BACKGROUND

End-stage kidney disease is an independent risk factor for stroke; however, the relationship between hemodialysis and stroke in Sub-Saharan Africa has not been established.

OBJECTIVE

To evaluate the incidence, associated factors, and clinical outcome of stroke among patients undergoing maintenance hemodialysis in Cameroon.

METHODS

A hospital-based retrospective study using data from the medical files of 1060 patients on maintenance hemodialysis (given twice a week) was conducted. Patients with stroke prior to starting hemodialysis were excluded. Socio-demographic data, comorbidities, dialysis parameters, and data concerning the diagnosis of stroke were retrieved and analyzed.

RESULTS

The dialysis vintage (duration of time on dialysis) averaged 11.4 ± 9.2 months. The incidence of stroke was 6.1 events per 1000 patient-years, with hemorrhagic stroke being most common (66%). Eighty percent of strokes occurred before the 30th month of dialysis. Sixty percent of strokes occurred within 24 h of a dialysis session. Predictive factors for stroke were diabetes mellitus (p = 0.026), heart failure (p = 0.045), poor dialysis compliance (p = 0.001), and short vintage (p = 0.001). The overall mortality rate was 52% and was higher for hemorrhagic stroke (60%). The leading causes of death were multiple organ failure and sepsis.

CONCLUSION

The incidence of stroke is high among hemodialysis patients in Cameroon and hemorrhagic stroke is the commonest type. Diabetes and heart failure triple the risk of stroke. Mortality in patients who suffered a stroke was high.

Changes in the Risk of Stroke in Dialysis Patients: A Retrospective Analysis over the Last 40 Years

The stroke incidence in hemodialysis (HD) patients is high, but the associated factors remain largely unknown. This study aimed to analyze stroke incidence in HD patients and changes in risk factors. Data of 291 patients were retrospectively analyzed. The cumulative stroke incidences were 21.6% at 10 years and 31.5% at 20. Diabetic nephropathy (DN) significantly increased overall stroke (hazard ratio (HR), 2.24; 95% confidence interval (CI), 1.21-4.12; p = 0.001) and ischemic stroke (HR, 2.16; 95% CI, 1.00-4.64; p = 0.049). Patients treated with online HDF were less likely to have overall stroke (HR, 0.13; 95% CI, 0.03-0.56; p = 0.006) and ischemic stroke (HR, 0.08; 95% CI, 0.01-0.60; p = 0.014). DN (HR, 1.56; 95% CI, 1.08-2.27; p = 0.019) and age >80 years at HD initiation (20-49 years old; HR 0.13, 95% CI, 0.05-0.35, p < 0.001 and age 50-79 years; HR 0.42, 95% CI, 0.26-0.66, p < 0.001 (reference: age >80 years)) were significantly associated with stroke and/or death events. Over time, stroke risk increased in HD patients, due to the increasing number of DN. Although dialysis technology has advanced over time, these advances could not overcome other risk factors for stroke. Further increase in stroke and mortality due to aging remains a concern.

Management of diabetes mellitus in dialysis patients: Obstacles and challenges

BACKGROUND AND AIMS

Diabetic kidney disease (DKD) is a major health issue that is associated with an increased risk of morbidity and mortality. The treatment of DKD is challenging given changes in blood glucose homeostasis, unclear accuracy of glucose metrics, and altered kinetics of the blood glucose-lowering medications. There is uncertainty surrounding the optimal glycemic target in this population although recent epidemiologic data suggest that HbA1c ranges of 6-8%, as well as 7-9%, are associated with increased survival rates among diabetic dialysis patients. Furthermore, the treatment of diabetes in patients maintained on dialysis is challenging, and many blood glucose-lowering medications are renally metabolized and excreted hence requiring dose adjustment or avoidance in dialysis patients.

METHOD

ology: PubMed, Google Scholar, and Medline were searched for all literature discussing the management of diabetes in dialysis patients.

RESULTS

The literature was discussed under many subheadings providing the latest evidence in the treatment of diabetes in dialysis patients.

CONCLUSION

The management of diabetes in dialysis is very complex requiring a multi-disciplinary team involving endocrinologists and nephrologists to achieve targets and reduce morbidity and mortality.

Predictive value of ankle-brachial index for long-term events of ischemic stroke in hemodialysis patients

OBJECTIVES

The ankle-brachial index is a noninvasive modality to evaluate atherosclerosis and is a predictive role for future cardiovascular events and mortality. However, few studies have evaluated its relation to long-term future ischemic stroke in hemodialysis patients. Therefore, we examined the relationship between ankle-brachial index and ischemic stroke events among hemodialysis patients in a seven-year follow-up.

METHODS

A total of 84 patients were enrolled. Ankle-brachial index was assessed in January 2009. Primary outcomes included ischemic stroke. An ankle-brachial index < 0.9 was considered abnormal and 1.4 ≥ ankle-brachial index ≥ 0.9 to be normal ankle-brachial index.

RESULTS

Mean values for ankle-brachial index were 0.98 ± 0.21at study entrance. In addition, 28 patients encountered ischemic stroke in the seven-year follow-up. In univariate Cox regression analysis, old age (hazard ratio (HR): 1.065, 95% confidence interval (CI): 1.030-1.102, p < 0.001), low seven-year averaged serum phosphate levels (HR: 0.473, 95% CI: 0.306-0.730, p = 0.001), and abnormal ankle-brachial index (HR: 0.035, 95% CI: 0.009-0.145, p < 0.001) were risk factors for ischemic stroke. In multivariate Cox regression analysis for significant variables in univariate analysis, abnormal ankle-brachial index (HR: 0.058, 95% CI: 0.012-0.279, p < 0.001) and low seven-year averaged serum phosphate levels (HR: 0.625, 95% CI: 0.404-0.968, p = 0.035) remained the risk factors for ischemic stroke. The risk of ischemic stroke was 3.783-fold in patients with abnormal ankle-brachial index compared with patients with normal ankle-brachial index (HR: 3.783, 95% CI: 1.731-8.269, p = 0.001).

CONCLUSIONS

These findings suggest that ankle-brachial index is an impressive predictor of future ischemic stroke among hemodialysis patients.

Outcomes Following Ischemic Stroke in Older Patients With CKD Stages 4 and 5: A Retrospective Cohort Study

RATIONALE & OBJECTIVE

The associations between ischemic stroke and time to dialysis initiation and/or death in adults with late-stage chronic kidney disease (CKD) have not been explored. We sought to measure the rate and factors associated with stroke in CKD stages 4 and 5 (CKD4-5) and assess the association of stroke with initiation of dialysis and death.

STUDY DESIGN

Retrospective cohort.

SETTING & PARTICIPANTS

Patients with CKD4-5 in Medicare 2007 to 2014.

EXPOSURE OR PREDICTOR

Ischemic stroke in CKD4-5.

OUTCOMES

Initiation of maintenance dialysis or death.

ANALYTICAL APPROACH

Cox proportional hazard modeling assessed factors associated with ischemic stroke. A matched analysis (stroke/no stroke) estimated the cumulative incidence of incident kidney failure and death, treated as competing events. Simulations using a state transition model determined differences in expected time to kidney failure or death and death alone for patients with and without stroke with CKD5.

RESULTS

123,251 patients with CKD4 and 22,054 with CKD5 were identified. Mean ages were 81.0 and 79.2 years, respectively. Female sex (HRs of 1.21 [95% CI, 1.12-1.31] and 1.39 [95% CI, 1.04-1.86] for CKD4 and CKD5, respectively) and black race (HRs of 1.25 [95% CI, 1.12-1.39] and 1.12 [95% CI, 0.80-1.58] for CKD4 and CKD5, respectively) were factors associated with ischemic stroke. Rates for 30-day mortality were 13.3% and 18.8%, and for 1-year mortality, 40.0% and 38.2%. For patients with CKD5, kidney failure or death occurred an average of 3.6 months sooner for patients with an ischemic stroke, and death (irrespective of kidney failure), a mean of 24.3 months sooner.

LIMITATIONS

Study design cannot determine causality; lack of data for stroke severity.

CONCLUSIONS

Female sex and black race were associated with increased risk for stroke in CKD4 and CKD5. In CKD5, stroke was associated with a shorter time to kidney failure or death by nearly 4 months, and to death, by more than 2 years.

Impact of atrial fibrillation on the risk of ischemic stroke in patients on hemodialysis: BOREAS-HD3 Study

BACKGROUND

Atrial fibrillation (AF) is an established risk factor for ischemic stroke in a general population. However, its impact in patients on hemodialysis (HD), a group with a high risk for stroke, is still controversial. Here we examined this issue in a Japanese cohort.

METHODS

This study was designed as a multicenter cohort study. HD patients (n = 1,067) were enrolled from 22 institutes in January 2009 and followed up for 3 years. Patients with missing data (n = 196) or kidney transplantation (n = 4) were excluded, and 867 patients contributed to the analysis of the risk of new-onset of ischemic stroke.

RESULTS

At baseline, AF was observed in 123 patients (14.2%, AF group) and not in the others (n = 744: 85.8%, non-AF group). During a follow-up period of 31.3 months, the cumulative incidence rate for ischemic stroke was significantly higher in the AF group than in the non-AF group (6.5% vs. 2.9%, p < 0.05). In Cox regression analysis, AF was a significant independent risk factor for new-onset of ischemic stroke after adjustment for age, sex, prior history of ischemic stroke, use of warfarin, dialysis vintage, comorbidity of diabetic nephropathy, and interdialytic weight gain (hazard ratio 2.17-2.68).

CONCLUSION

Present analyses using comprehensive adjustment for multiple confounders, including prior history of ischemic stroke, indicated that AF independently increases the risk of new-onset of ischemic stroke by more than twofold in Japanese HD patients.

Paraoxonase 1 gene polymorphisms concerning non-insulin-dependent diabetes mellitus nephropathy in hemodialysis patients

AIMS

Data on involvement of paraoxonase 1 gene (PON1) in non-insulin-dependent diabetes mellitus (NIDDM) nephropathy are scarce. We investigated PON1 polymorphisms concerning end-stage NIDDM nephropathy and atherosclerotic complications in NIDDM nephropathy patients treated with hemodialysis (HD).

METHODS

In NIDDM nephropathy (n = 402) and non-diabetic (n = 998) HD subjects, we obtained PON1 polymorphisms by HRM analysis (rs662) or predesigned TaqMan SNV Genotyping Assay (rs854560, rs705379).

RESULTS

Only PON1 rs705379 was associated with end-stage NIDDM nephropathy in the recessive (OR 1.451, 95% CI 1.104-1.906, P = 0.009) and additive (OR 1.398, 95%CI 1.009-1.936, P = 0.046) inheritance modes. NIDDM nephropathy patients bearing the rs854560 T allele were at higher risk for ischemic cerebral stroke (OR 2.087, 95%CI 1.145-3.801, P = 0.016). In non-diabetic patients but not NIDDM nephropathy subjects, atherogenic dyslipidemia corresponded with PON1 rs662 A allele and PON1 rs854560 TT homozygosity.

CONCLUSIONS

In HD patients, NIDDM nephropathy correlates with the TT genotype of PON1 rs705379. The rs854560 T allele indicates a higher risk for atherosclerotic diseases in NIDDM nephropathy subjects. The T alleles of both PON1 SNVs are known as low expression variants downregulated serum PON1 activity. An increase of diminished PON1 activity may be a target in the prevention of NIDDM nephropathy and NIDDM atherosclerotic complications.

The Contribution of Kidney Disease to Cognitive Impairment in Patients with Type 2 Diabetes

PURPOSE OF REVIEW

This review focuses on the relationships between diabetes, cognitive impairment, and the contribution of kidney disease.

RECENT FINDINGS

We review the independent contributions of parameters of kidney disease, including albuminuria, glomerular filtration, bone/mineral metabolism, and vitamin D synthesis, on cognitive performance in patients with diabetes. Potential pathophysiologic mechanisms underlying these associations are discussed highlighting gaps in existing knowledge. Finally, effects of the dialysis procedure on the brain and cognitive performance are considered. Emphasis is placed on novel non-invasive screening tools with the potential to preserve cerebral perfusion during hemodialysis and limit cognitive decline in patients with diabetic ESKD. Patients with type 2 diabetes and advanced chronic kidney disease suffer a higher prevalence of cognitive impairment. This is particularly true in patients with diabetes and end-stage kidney disease (ESKD).

Risk Factors and Outcomes of Cerebral Stroke in End-Stage Renal Disease Patients Receiving Hemodialysis

OBJECTIVE

Dialysis patients have a higher incidence of stroke, and outcomes are often poor. Diabetic nephropathy (DN) is a stroke risk-factor, but the importance is unclear in dialysis patients. This study investigated the stroke features and risk factors in hemodialysis (HD) patients.

METHODS

All end-stage renal disease patients undergoing HD at Teraoka Memorial Hospital dialysis center were identified, with 195 recruited. Baseline clinical characteristics were collected, and the clinical outcomes and related factors of stroke in HD patients were retrospectively analyzed. The incidence rate of stroke and mortality were calculated using Kaplan-Meier survival analysis. Factors potentially related to stroke were analyzed by the log-rank test and Cox proportional hazards model for univariate and multivariate analysis.

RESULTS

In total, 21.0% (41 of 195) patients developed stroke. The incidence rates of stroke per 1000 patient-years were 53.6, 65.2, and 34.0 in all HD patients, DN patients, and non-DN patients, respectively. The cumulative incidence rates of stroke in all HD patients, DN patients, and non-DN patients per 5 years, and per 10 years were 22.6%, 43.5%; 28.8%, 59.6%; and 17.6%, 31.1%, respectively. The incidence rate of stroke in the DN patients was significantly higher than in the non-DN patients (P = .013). DN was the significant risk factor for stroke by multivariate analysis (hazard ratio 2.63, 95% confidence interval 1.08-7.85; P = .032).

CONCLUSIONS

This study revealed the trends of stroke in HD patients at a single institution in Japan. DN was shown to be a significant risk factor for stroke in HD patients.

Impact of prior stroke on major clinical outcome in chronic kidney disease: the Salford kidney cohort study

Background

Chronic kidney disease (CKD) is an independent risk factor for stroke in the general population. The impact of prior stroke on major clinical outcomes in CKD populations is poorly characterised.

Methods

The Salford Kidney Study is a UK prospective cohort of more than 3000 patients recruited since 2002 and followed until March 2018. Multivariable Cox regression examined associations of stroke at two time points; cohort inception, and at dialysis initiation, with risks of death, non-fatal cardiovascular events (NFCVE) and end stage renal disease (ESRD).

Results

277 (9.1%) of 3060 patients suffered a prior stroke and this was associated with mortality, ESRD and future NFCVE after cardiovascular risk factor adjustments. Median survival for prior stroke patients was 40 months vs 77 months in patients without a stroke. Prior stroke was independently associated with mortality (HR 1.20 95%CI 1.0–1.43, p = 0.05). Of 579 patients who reached ESRD and commenced dialysis, a prior stroke (N = 48) was independently associated with mortality. Median survival for the prior stroke group was 29 months compared with 50 months for the non-stroke group. Only 70 and 75% of patients who had suffered an ischaemic stroke were prescribed antiplatelets or statins respectively.

Conclusions

A diagnosis of stroke is strongly and independently associated with several adverse clinical outcomes for patients with CKD. Prior stroke profoundly alters cardiovascular risk in CKD patients. Greater attention to primary and secondary preventive strategies is warranted which may improve these outcomes.

Chronic kidney disease in the pathogenesis of acute ischemic stroke

Chronic kidney disease has a graded and independent inverse impact on cerebrovascular health. Both thrombotic and hemorrhagic complications are highly prevalent in chronic kidney disease patients. Growing evidence suggests that in chronic kidney disease patients, ischemic strokes are more common than hemorrhagic strokes. Chronic kidney disease is asymptomatic until an advanced stage, but mild to moderate chronic kidney disease incites various pathogenic mechanisms such as inflammation, oxidative stress, neurohormonal imbalance, formation of uremic toxins and vascular calcification which damage the endothelium and blood vessels. Cognitive dysfunction, dementia, transient infarcts, and white matter lesions are widespread in mild to moderate chronic kidney disease patients. Uremic toxins produced after chronic kidney disease can pass through the blood-brain barrier and mediate cognitive dysfunction and neurodegeneration. Furthermore, chronic kidney disease precipitates vascular risk factors that can lead to atherosclerosis, hypertension, atrial fibrillation, and diabetes. Chronic kidney disease also exacerbates stroke pathogenesis, worsens recovery outcomes, and limits the eligibility of stroke patients to receive available stroke therapeutics. This review highlights the mechanisms involved in the advancement of chronic kidney disease and its possible association with stroke.

The Association of Atrial Fibrillation and Ischemic Stroke in Patients on Hemodialysis: A Competing Risk Analysis

Background

Stroke is common in patients with end-stage renal disease (ESRD) treated with hemodialysis (HD) and associated with high mortality rate. In the general population, atrial fibrillation (AF) is a major risk factor for stroke and therapeutic anticoagulation is associated with risk reduction, whereas in ESRD the relationship is less clear.

Objective

The purpose of this study is to demonstrate the influence of AF on stroke rates and probability in those on HD following competing risk analyses.

Design

A national record linkage cohort study.

Setting

All renal and stroke units in Scotland, UK.

Patients

All patients with ESRD receiving HD within Scotland from 2005 to 2013 (follow-up to 2015).

Measurements

Demographic, clinical, and laboratory data were linked between the Scottish Renal Registry, Scottish Stroke Care Audit, and hospital discharge data. Stroke was defined as a fatal or nonfatal event and mortality derived from national records.

Methods

Associations for stroke were determined using competing risk models: the cause-specific hazards model and the Fine and Gray subdistribution hazards model accounting for the competing risk of death in models of all stroke, ischemic stroke, and first-ever stroke.

Results

Of 5502 patients treated with HD with 12 348.6-year follow-up, 363 (6.6%) experienced stroke. The stroke incidence rate was 26.7 per 1000 patient-years. Multivariable regression on the cause-specific hazard for stroke demonstrated age, hazard ratio (HR) (95% confidence interval [CI]) = 1.04 (1.03-1.05); AF, HR (95% CI) = 1.88 (1.25-2.83); prior stroke, HR (95% CI) = 2.29 (1.48-3.54), and diabetes, HR (95% CI) = 1.92 (1.45-2.53); serum phosphate, HR (95% CI) = 2.15 (1.56-2.99); lower body weight, HR (95% CI) = 0.99 (0.98-1.00); lower hemoglobin, HR (95% CI) = 0.88 (0.77-0.99); and systolic blood pressure (BP), HR (95% CI) = 1.01 (1.00-1.02), to be associated with an increased stroke rate. In contrast, the subdistribution HRs obtained following Fine and Gray regression demonstrated that AF, weight, and hemoglobin were not associated with stroke risk. In both models, AF was significantly associated with nonstroke death.

Limitations

Our analyses derive from retrospective data sets and thus can only describe association not causation. Data on anticoagulant use are not available.

Conclusions

The incidence of stroke in HD patients is high. The competing risk of "prestroke" mortality affects the relationship between AF and risk of future stroke. Trial designs for interventions to reduce stroke risk in HD patients, such as anticoagulation for AF, should take account of competing risks affecting associations between risk factors and outcomes.

The comparison of risk of stroke in patients with peritoneal dialysis and hemodialysis: A systematic review and meta-analysis

OBJECTIVE

Several studies have demonstrated that end-stage renal disease (ESRD) patients on dialysis are at higher risk for cerebrovascular events, especially those on hemodialysis. However, the risk of stroke in patients on peritoneal dialysis (PD) compared to those on hemodialysis (HD) remains unclear. We performed this meta-analysis to assess the risks of stroke in ESRD patients on PD compared to HD.

METHODS

A systematic review was conducted using MEDLINE, EMBASE, Cochrane databases from inception through January 2018 to identify studies that evaluated the risks of stroke (all types of stroke, ischemic stroke or hemorrhagic stroke) in ESRD patients on different dialysis modalities. Effect estimates from the individual study were extracted and combined using random-effect, generic inverse variance method of DerSimonian and Laird.

RESULTS

Fifteen cohort studies with a total of 1 289 572 ESRD patients (over 1 140 942 on HD and 122 534 on PD) were enrolled. Compared with HD, PD was associated with a significantly decreased risk of hemorrhagic stroke with pooled OR of 0.84 (95% CI: 0.76-0.92). However, there were no differences in risks of all types of stroke or ischemic stroke in those on PD compared to HD with pooled ORs of 1.06 (95% CI: 0.91-1.22) and 1.01 (95% CI: 0.80-1.18,), respectively.

CONCLUSIONS

PD status is associated with 16% lower risk of hemorrhagic stroke compared to HD, but the risks of all types of stroke and hemorrhagic stroke are not statistically different in PD patients when compared to HD patients.

Atrial fibrillation in dialysis patients: is there a place for non-vitamin K antagonist oral anticoagulants?

Atrial fibrillation (AF) occurs approximately in 3% of general population, with greater prevalence in elderly. Non-vitamin K-dependent oral anticoagulant agents (NOACs) according to the current European guidelines are recommended for patients with AF at high risk for stroke as a first-choice treatment. NOACs are not inferior to warfarin or some of them are better than warfarin in reducing the rate of ischemic stroke. Moreover, they significantly reduce the rate of intracranial hemorrhages, major bleedings, and mortality compared with warfarin. Nevertheless according to ESC guidelines, NOACs are not recommended in patients with creatinine clearance < 30 mL/min. Observational studies provide contradictive data. Only few new trials are ongoing. Therefore, it is not clear if NOACs should be in the future prescribed to patients with advanced CKD and those on dialysis. Moreover, the risk of stroke and bleeding is much higher in such population than in patients without end-stage renal disease (ESRD). The authors provide data on pros and cons of use of NOACs in ESRD patients with AF.

Stroke risk and outcomes in patients with chronic kidney disease or end-stage renal disease: Two nationwide studies

Background and aims

Because the risk and outcomes of stroke in patients with chronic kidney disease (CKD) or end-stage renal disease (ESRD) were unclear, we evaluated these risks using a retrospective cohort study and a nested cohort study.

Methods

We used Taiwan’s National Health Insurance Research Database to identify 1378 patients aged ≥20 years who had ESRD in 2000–2004. An age- and sex-matched CKD cohort (n = 5512) and a control cohort (n = 11,024) were selected for comparison. Events of incident stroke were considered as outcome during the follow-up period in 2000–2013, and we calculated adjusted hazard ratios (HR) and 95% CIs of stroke associated with CKD or ESRD. We further used matching procedure with propensity score to estimate the risk of stroke for control group, CKD patients, and EDRD patients. A nested cohort study of 318,638 hospitalized stroke patients between 2000 and 2010 also was conducted to analyze the impact of CKD and ESRD on post-stroke mortality.

Results

Before propensity-score matching, the incidences of stroke for controls, CKD patients and ESRD patients were 6.57, 13.3, and 21.7 per 1000 person-years, respectively. Compared with control group, the adjusted HRs of stroke were 1.49 (95% CI, 1.32–1.68) and 2.39 (95% CI, 1.39–2.87) for people with CKD or ESRD respectively, and were significantly higher in both sexes and every age group. After propensity-score matching, the HRs of stroke for patients with CKD and ESRD were 1.51 (95% CI 1.24–1.85) and 2.08 (95% CI 1.32–3.26), respectively, during the follow-up period. Among hospitalized stroke patients, adjusted rate ratio (RR) of post-stroke mortality in CKD and ESRD cohorts were 1.44 (95% CI, 1.33–1.56) and 2.62 (95% CI, 2.43–2.82) respectively compared with control.

Conclusions

CKD and ESRD patient groups thus faced significantly higher risk of stroke and post-stroke mortality. Risk factor identification and preventive strategies are needed to minimize stroke risk and post-stroke mortality in these vulnerable patient groups.

Association Between Stroke Risk and Metformin Use in Hemodialysis Patients With Diabetes Mellitus: A Nested Case-Control Study

BACKGROUND

Metformin use reduces the incidence and severity of stroke in patients with type 2 diabetes mellitus (DM). The benefits of metformin for stroke have not been examined in hemodialysis patients with DM.

METHODS AND RESULTS

Using the National Health Insurance Research Database, we identified 17 760 patients with DM and new-onset hemodialysis between 2001 and 2013. Of these, 1898 patients hospitalized for either ischemic or hemorrhagic stroke were matched to 7592 control patients according to sex, age, and year of initial hemodialysis therapy by using incidence sampling. The association between metformin use and stroke risk was estimated using conditional logistic regression after adjustment for hemodialysis frequency, comorbidity, and prescribed medications. Metformin use was recorded before the date of stroke admission and the date of pseudostroke of the case and control patients, respectively. Results showed that hemodialysis patients with ischemic stroke were more likely to use metformin than the controls 1 year before the date of stroke admission (adjusted odds ratio: 1.64; 95% confidence interval, 1.32-2.04). The association was evident within 90 days before the index date (adjusted odds ratio: 1.81; 95% confidence interval, 1.27-2.60). The results were consistent with those of hemodialysis patients with hemorrhagic stroke. Metformin use remained a risk factor for stroke in patients treated with antihypertensive, sulfonylurea, and antiplatelet drugs.

CONCLUSIONS

This nested case-control study is the first to show that metformin use is associated with stroke risk in hemodialysis patients with DM. We suggest that metformin should not be used by hemodialysis patients with DM.

Impact of blood urea nitrogen to creatinine ratio on mortality and morbidity in hemodialysis patients: The Q-Cohort Study

The association between blood urea nitrogen to creatinine ratio (UCR) and survival is uncertain in hemodialysis patients. We examined the influence of UCR on mortality and morbidity in hemodialysis patients. A total of 3,401 hemodialysis patients were prospectively followed for 4 years. The association between UCR with overall survival was analyzed using a Cox regression model. During a 4-year follow-up period, 545 patients died from any cause and 582 experienced MACE, 392 with coronary heart disease (CHD), 114 with infection-related death, 77 with hemorrhagic stroke, 141 with ischemic stroke, and 107 with cancer death. Every 1 increase in UCR level was significantly associated with an increased risk for all-cause mortality (hazard ratio [HR] 1.07; 95% confidence interval [CI] 1.03–1.12), CHD (HR 1.08; 95% CI 1.02–1.14), and infection-related death (HR 1.11; 95% CI 1.02–1.21). There was no evidence of a significant association between UCR and death from cancer, and incidence of stroke. A high UCR was significantly associated with an increased risk for all-cause mortality, infection-related death and incidence of CHD in hemodialysis patients.

Predicting in a predicament: Stroke and hemorrhage risk prediction in dialysis patients with atrial fibrillation

Whether to anticoagulate dialysis patients with atrial fibrillation is a common clinical dilemma with limited high-quality data to inform decision-making. While the efficacy and safety of anticoagulation for stroke prevention in dialysis patients with atrial fibrillation has long been debated and remains unclear, the more upstream issue of stroke risk assessment from atrial fibrillation has received relatively little attention. In the general population, a handful of risk scores to help predict stroke and hemorrhage risk in the setting of atrial fibrillation are widely validated and applied in clinical practice. But are they applicable to the dialysis population? The most commonly used stroke risk scores, CHADS2 and CHA2DS2-VASC, have limited validation in the dialysis population, and when validated, have shown poor performance (c-statistics <0.70). Stroke risk scores derived in the general atrial fibrillation population may perform poorly in dialysis patients for a number of reasons. Dialysis patients have unique stroke risk factors, such as chronic inflammation and vascular calcification, and a much higher competing risk of death, none of which are accounted for in current risk scores. Further complicating the dilemma of anticoagulation is hemorrhage risk, which is known to be exceedingly high in dialysis patients. Currently available hemorrhage risk scores, such as HAS-BLED, have not been validated in dialysis patients and will likely underestimate hemorrhage risk. Moving forward, risk tools specific to the dialysis population are needed to accurately assess and balance stroke and hemorrhage risks in dialysis patients with atrial fibrillation.

Bleeding Risk of Antithrombotic Treatment in Patients on Hemodialysis

BACKGROUND

The risk-benefit of antithrombotic treatment (ATT) has not been established in patients on dialysis. Our objective was to determine the influence of ATT on the risk of hemorrhage in patients on hemodialysis.

METHODS

We included patients who began dialysis between 2003 and 2007. We determined the rates of fatal bleeding or bleeding leading to hospitalization or transfusion.

RESULTS

Two hundred twenty-one patients were included. Over the follow-up period (45.5 ± 34 months), there were 76 hemorrhages in 52 patients. There were 10 fatal bleedings. The annual incidence of patients presenting with hemorrhagia was 6.2%. Bleeding occurred in 5.2% of those being treated with aspirin, 7% with acenocumarol, 12.3% with clopidogrel, 15.2% with aspirin + clopidogrel, 45.9% with anticoagulants + antiplatelets, 49.6% with low-molecular-weight heparin, and 3.9% without ATT. On multivariate analysis, masculine gender [hazard ratio (HR): 2.421; 95% confidence interval (CI), 1.261-4.650; P = 0.003], treatment with dicumarins (HR: 2.406; 95% CI, 1.013-5.718; P = 0.047), treatment with clopidogrel (HR: 2.697; 95% CI, 1.440-5.051; P = 0.002), and treatment with low-molecular-weight heparin (HR: 21.463; 95% CI, 9.067-50.806; P = 0.001) were independent predictors of bleeding.

CONCLUSIONS

ATT increases the risk of bleeding in patients on hemodialysis. The incidence of hemorrhage varies with the type of antithrombotics used.

Association of multiple ischemic strokes with mortality in incident hemodialysis patients: an application of multistate model to determine transition probabilities in a retrospective observational cohort

Background

Little is known about the effect of multiple, or subsequent, ischemic strokes in patients receiving hemodialysis.

Methods

We undertook a retrospective cohort study of incident hemodialysis patients with Medicare coverage who had experienced a first ischemic stroke. Factors associated with either a subsequent ischemic stroke or death following a first new stroke were modeled. A multistate model with Cox proportional hazards was used to predict transition probabilities from first ischemic stroke to either subsequent stroke or to death, and the demographic and clinical factors associated with the respective transition probabilities were determined. Effect of a subsequent ischemic stroke on survival was quantified.

Results

Overall, 12,054 individuals (mean age 69.7 years, 41.3 % male, 53.0 % Caucasian and 34.0 % African-American) experienced a first new ischemic stroke. Female sex was associated with an increased risk of having a subsequent ischemic stroke (adjusted hazard ratio 1.37, 95 % confidence intervals 1.20 – 1.56, P < 0.0001); African-Americans, as compared to Caucasians, had lower likelihood of dying after a first new ischemic stroke (0.81, 0.77 – 0.85, P < 0.0001). A subsequent stroke trended towards having a higher likelihood of transitioning to death compared to a first new ischemic stroke on dialysis (1.72, 0.96 – 3.09, P = 0.071). When a subsequent ischemic stroke occurs at 24 months, probability of survival dropped >15 %, in absolute terms, from 0.254 to 0.096, with substantial drops observed at subsequent time points such that the probability of survival was more than halved.

Conclusions

Likelihood of subsequent ischemic stroke and of survival in hemodialysis patients appears to vary by sex and race: females are more likely than males to experience a subsequent ischemic stroke, and Caucasians are more likely than African-Americans to die after a first new ischemic stroke. The risk of a transitioning to a subsequent stroke (after having had a first) increases until about 1 year, then decreases. Subsequent strokes are associated with decreased probability of survival, an effect which increases as time since first stroke elapses. This information may be of assistance to clinicians when counseling hemodialysis patients about the implications of recurrent ischemic stroke.

Modulation of stroke risk in chronic kidney disease

Stroke is the second most common cause of death and the leading cause of neurological disability worldwide, with huge economic costs and tragic human consequences. Both chronic kidney disease (CKD) and end-stage kidney disease are associated with a significantly increased risk of stroke. However, to date this has generated far less interest compared with the better-recognized links between cardiac and renal disease. Common risk factors for stroke, such as hypertension, hypercholesterolaemia, smoking and atrial fibrillation, are shared with the general population but are more prevalent in renal patients. In addition, factors unique to these patients, such as disorders of mineral and bone metabolism, anaemia and its treatments as well as the process of dialysis itself, are all also postulated to further increase the risk of stroke. In the general population, advances in medical therapies mean that effective primary and secondary prevention therapies are available for many patients. The development of specialist stroke clinics and acute stroke units has also improved outcomes after a stroke. Emerging therapies such as thrombolysis and thrombectomy are showing increasingly beneficial results. However, patients with CKD and on dialysis have different risk profiles that must be taken into account when considering the potential benefits and risks of these treatments. Unfortunately, these patients are either not recruited or formally excluded from major clinical trials. There is still much work to be done to harness effective stroke treatments with an acceptable safety profile for patients with CKD and those on dialysis.

Prevalence and Impact on Stroke in Patients Receiving Maintenance Hemodialysis versus Peritoneal Dialysis: A Prospective Observational Study

BACKGROUND

Patients undergoing maintenance dialysis are at increased risk of stroke, however, less is known about the prevalence and impact on stroke in the patients.

METHODS

In this prospective cohort study, 590 patients undergoing hemodialysis (HD; n = 285) or peritoneal dialysis (PD; n = 305) from January 1, 2008 to December 31, 2012 were recruited. Baseline demographic, clinical, and laboratory data were collected. Timeline incidence data were analyzed using a Poisson model. The Cox proportional hazards regression assessed adjusted differences in stroke risk, a multivariate analysis was also performed.

RESULTS

62 strokes occurred during 1258 total patient-years of follow-up. Stroke occurred at a rate of 49.2/1,000 patient-years with a predominance in HD patients compared with PD patients (74.0 vs. 31.8/1,000 patient-years). The cumulative hazard of developing stroke was significantly higher in HD patients (hazard ratio [HR], 1.75; 95% confidence interval [CI], 1.15-3.62; p = 0.046) after adjusting for potential confounders. HD patients had an increased risk of ischemic stroke (HR, 2.62; 95% CI, 1.56-4.58; p = 0.002). The risk of hemorrhagic stroke was not significantly different between PD and HD patients. On multivariate Cox analysis, risk factors of stroke in both HD and PD patients were older age, diabetes, and cardiovascular disease. Other independent risk factors of stroke were lower albumin-corrected calcium in HD patients and higher triglycerides in PD patients.

CONCLUSIONS

Patients undergoing PD were less likely to develop ischemic stroke than those undergoing HD. Comprehensive control of diabetes, cardiovascular disease, calcium-phosphorus metabolism, and triglyceride levels may be useful preventive strategies for stroke in dialysis patients.

Prognostic impact of atrial fibrillation on clinical outcomes of acute coronary syndromes, heart failure and chronic kidney disease

Atrial fibrillation (AF) is the most common type of sustained arrhythmia, which is now on course to reach epidemic proportions in the elderly population. AF is a commonly encountered comorbidity in patients with cardiac and major non-cardiac diseases. Morbidity and mortality associated with AF makes it a major healthcare burden. The objective of our article is to determine the prognostic impact of AF on acute coronary syndromes, heart failure and chronic kidney disease. Multiple studies have been conducted to determine if AF has an independent role in the overall mortality of such patients. Our review suggests that AF has an independent adverse prognostic impact on the clinical outcomes of acute coronary syndromes, heart failure and chronic kidney disease.

Risk of Stroke in Patients with ESRD

BACKGROUND AND OBJECTIVES

This study aimed to determine absolute and excess stroke risks in people with ESRD compared with the general population.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This cohort study used data linkage between the Australia and New Zealand Dialysis and Transplant Registry and hospital and death records for 10,745 people with ESRD in New South Wales from 2000 to 2010. For the general population, Australian Institute of Health and Welfare hospital usage records and Australian Bureau of Statistics census data were used. Rates and standardized incidence rate ratios of hospitalization with a stroke were calculated.

RESULTS

People with ESRD had 640 hospitalizations with stroke in 49,472 person-years of follow-up (1294 per 100,000 person-years), and people in the general population had 338,392 hospitalizations with stroke (212 per 100,000 person-years), an incidence rate ratio of 3.32 (95% confidence interval, 3.31 to 3.33). Excess risk was greater for women (incidence rate ratio, 5.14; 95% confidence interval, 5.11 to 5.18) than men (incidence rate ratio, 2.52; 95% confidence interval, 2.51 to 2.54; P for interaction <0.001) and decreased with age. People ages 35-39 years old with ESRD had an 11 times increased risk of stroke (incidence rate ratio, 11.08; 95% confidence interval, 9.41 to 13.05), and risk in people ages ≥85 years old increased 2-fold (incidence rate ratio, 2.04; 95% confidence interval, 1.87 to 2.23; P for interaction <0.001). Excess risk was greater for intracerebral hemorrhage (incidence rate ratio, 4.18; 95% confidence interval, 4.11 to 4.26) than ischemic stroke (incidence rate ratio, 3.43; 95% confidence interval, 3.40 to 3.45; P for interaction <0.01).

CONCLUSIONS

People with ESRD have a substantially higher risk of stroke, particularly women and young people, and hemorrhagic stroke. Future work could investigate effective and safe interventions for primary and secondary prevention of stroke in people with ESRD.

Valvular calcifications at the start of dialysis predict the onset of cardiovascular events in the course of follow-up

OBJECTIVE

To analyse the presence of VC at the start of dialysis and its relationship with events and/or death from cardiovascular causes in the course of follow-up.

METHODS

In the study, we included patients who started dialysis between November 2003 and September 2007. In the first month of treatment, we assessed the presence of VC by Doppler echocardiography, along with demographic factors and risk factors for cardiovascular disease, coronary artery disease, stroke, atrial fibrillation (AF), and cardiac dimensional and functional electrocardiographic and echocardiographic parameters. The biochemistry values assessed were: haemoglobin, calcium/phosphorous/iPTH metabolism, cholesterol and fractions, triglycerides, troponin I, albumin, CRP and glycosylated haemoglobin. We analysed the association between VC and the presence of myocardial infarction (MI), stroke and/or death from cardiovascular causes up to transplantation, death or the end of the study (December 2012).

RESULTS

Of 256 enrolled patients (83% haemodialysis, 17% peritoneal dialysis), 128 (50%) had VC (mitral: 39, aortic: 20, both: 69). In the multivariate analysis, VC was associated with older age (OR: 1.110; 95% CI: 1.073-1.148; p = 0.000) and lower albumin levels (OR: 0.29; 95% CI: 0.14-0.61; p = 0.001). In a follow-up lasting 42.1 ± 30.2 months (898.1 patient-years), 68 patients suffered MI, stroke and/or died from cardiovascular causes. In the Cox regression analysis, older age (HR: 1.028; 95% CI: 1.002-1.055; p = 0.037), coronary artery disease and/or stroke (HR: 1.979; 95% CI: 1.111-3.527; p = 0.021), AF (HR: 2.474; 95% CI: 1.331-4.602; p = 0.004), and the presence of VC at the start of dialysis (HR: 1.996; 95% CI: 1.077-3.700; p = 0.028) were the predictor variables for the occurrence of the analysed events.

CONCLUSIONS

The prevalence of VC at the start of dialysis is high and its presence predicts the occurrence of events and/or cardiovascular death in the course of follow-up.

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.

Ischemic stroke: the impact of renal dysfunction on 1-year mortality

BACKGROUND

Atherosclerosis is accelerated in patients with different stages of chronic renal failure. Renal dysfunction predicts mortality in patients with myocardial infarction and congestive heart failure. Less is known about the impact of renal dysfunction on mortality after ischemic stroke. The aim of the study was to investigate the impact of renal dysfunction on 1-year mortality.

PATIENTS AND METHODS

All 390 patients (207 men and 183 women) suffered from ischemic stroke in 1-year period were included in our study. Telephonic follow-up after 1 year was performed. The mean age of our patients was 71.0 ± 11.6 years, ranged from 36 to 96 years. Glomerular filtration rate (GFR) was calculated according to abbreviated Modification of Diet in Renal Disease formula. At admission and at discharge National Institutes of Health Stroke Scale (NIHSS) were performed.

RESULTS

The mean GFR in our patients was 66.0 ± 20.68 ml/min/1.73 m(2). There were 123 (31.5 %) deaths in 1-year period. Patients who died were older (P < 0.001), had higher NIHSS at admission and at discharge (both P < 0.001), higher high-sensitive C-reactive protein (P = 0.002), lower albumin (P < 0.001), lower GFR (P = 0.044), had more frequent atrial fibrillation (P < 0.001), and were less frequent actual smokers (P = 0.003). No differences in presence of diabetes and hypertension, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and triglycerides between patients who died or survived were found. With Cox multivariable regression analysis age (P = 0.037), gender (P = 0.005), NIHSS at admission (P = 0.005) and discharge (P < 0.001), albumin (P = 0.005) and also GFR (P = 0.025) were predictors of 1-year mortality.

CONCLUSIONS

In patients with ischemic stroke, renal dysfunction (decreased GFR) was associated with 1-year mortality. GFR was independent predictor of mortality.

Relationship between stroke and mortality in dialysis patients

BACKGROUND AND OBJECTIVES

Stroke is common in patients undergoing long-term dialysis, but the implications for mortality after stroke in these patients are not fully understood.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A large cohort of dually-eligible (Medicare and Medicaid) patients initiating dialysis from 2000 to 2005 and surviving the first 90 days was constructed. Medicare claims were used to ascertain ischemic and hemorrhagic strokes occurring after 90-day survival. A semi-Markov model with additive hazard extension was generated to estimate the association between stroke and mortality, to calculate years of life lost after a stroke, and to determine whether race was associated with differential survival after stroke.

RESULTS

The cohort consisted of 69,371 individuals representing >112,000 person-years of follow-up. Mean age±SD was 60.8±15.5 years. There were 21.1 (99% confidence interval [99% CI], 20.0 to 22.3) ischemic strokes and 4.7 (99% CI, 4.2 to 5.3) hemorrhagic strokes after cohort entry per 1000 patient-years. At 30 days, mortality was 17.9% for ischemic stroke and 53.4% for hemorrhagic stroke. The adjusted hazard ratio (AHR) depended on time since entry into the cohort; for patients who experienced a stroke at 1 year after cohort entry, for example, the AHR of hemorrhagic stroke for mortality was 25.4 (99% CI, 22.4 to 28.4) at 1 week, 9.9 (99% CI, 8.4 to 11.6) at 3 months, 5.9 (99% CI, 5.0 to 7.0) at 6 months, and 1.8 (99% CI, 1.5 to 2.1) at 24 months. The corresponding AHRs for ischemic stroke were 11.7 (99% CI, 10.2 to 13.1) at 1 week, 6.6 (99% CI, 6.4 to 6.7) at 3 months, and 4.7 (99% CI, 4.5 to 4.9) at 6 months, remaining significantly >1.0 even at 48 months. Median months of life lost were 40.7 for hemorrhagic stroke and 34.6 for ischemic stroke. For both stroke types, mortality did not differ by race.

CONCLUSIONS

Dialysis recipients have high mortality after a stroke with corresponding decrements in remaining years of life. Poststroke mortality does not differ by race.

Evidence for the prevention and treatment of stroke in dialysis patients

The risks of both ischemic and hemorrhagic stroke are particularly high in dialysis patients of any age and outcomes are poor. It is therefore important to identify strategies that safely minimize stroke risk in this population. Observational studies have been unable to clarify the relative importance of traditional stroke risk factors such as blood pressure and cholesterol in those on dialysis, and are affected by biases that usually make them an inappropriate source of data on which to base therapeutic decisions. Well-conducted randomized trials are not susceptible to such biases and can reliably investigate the causal nature of the association between a potential risk factor and the outcome of interest. However, dialysis patients have been under-represented in the cardiovascular trials which have proven net benefit of commonly used preventative treatments (e.g., antihypertensive treatments, low-dose aspirin, carotid revascularization, and thromboprophylaxis for atrial fibrillation), and there remains uncertainty about safety and efficacy of many of these treatments in this high-risk population. Moreover, the efficacy of renal-specific therapies that might reduce cardiovascular risk, such as modulators of mineral and bone disorder, online hemodiafiltration, and daily (nocturnal) hemodialysis, have not been tested in adequately powered trials. Recent trials have also demonstrated how widespread current practices could be causing stroke. Therefore, it is important that reliable information on the prevention and treatment of stroke (and other cardiovascular disease) in dialysis patients is generated by performing large-scale randomized trials of many current and future treatments.

Sudden death in incident dialysis patients

BACKGROUND

Sudden death (SD) constitutes one of the principal causes of death and is an important problem in healthcare provision. Cardiovascular diseases have a high prevalence in dialysis patients and constitute the principal cause of death. We sought to analyze retrospectively the incidence of SD in patients commencing dialysis and the factors related to its presence.

METHODS

We evaluated all the patients who began dialysis in our center between 1/11/2003 and 15/9/2007, and who were followed up until death, transplant, or study completion on 31/12/2012. We determined the presence of SD according to the following criteria: SD at 24 h (SD 24H): unexpected death occurring in the 24 h following the start of symptoms, or when the patient was found dead and had been seen alive 24 h earlier; SD at 1 h (SD 1H): death witnessed as occurring in the first hour following the start of symptoms.

RESULTS

We evaluated 285 patients, mean age 65.67 ± 15.7 years. In a follow-up of 39.9 ± 34.2 months (947.6 patient-years of follow-up) 168 died (59%), 28 (10%) patients presented SD 24H (2.9/100 patient-years), and 16 (6%) patients presented SD 1H (1.7/100 patient-years). In the multivariate analysis, having had a myocardial infarction or having had electrocardiographic abnormalities (Q wave, negative T wave, subendocardial lesion or QRS >120 ms) were the principal independent predictors of SD 24H (OR 7.83; 95% CI 2.20-27.86; p = 0.001) and of SD 1H (OR 13.43; 95% CI 1.56-115.42; p = 0.018).

CONCLUSIONS

SD on dialysis is very frequent. Two groups can be identified easily, with risk profiles clearly differentiated.

Stroke and renal dysfunction

Stroke is the most frequent neurological disease and represents a continuously evolving medical and social problem. Chronic kidney disease (CKD) is also an important worldwide public health problem. Renal dysfunction carries a substantial risk of cardiovascular morbidity and mortality and an independent, graded association between renal function and cardiovascular events was found. In the last 15years the link between CKD and cerebrovascular disease has become more apparent. Patients with end stage renal disease treated with maintenance hemodialysis have a much higher incidence of stroke than the general population and stroke is one of the major causes of death in these patients. Nowadays ischemic subtype of stroke is present in approximately 70% of dialysis patients. In population based studies conflicting results have been reported about the association between stroke and CKD before replacement therapy. However, in high risk patients, defined by the presence of either cardiovascular disease or cardiovascular risk factors, different stages of CKD are clearly associated with subsequent stroke. In patients with stroke the exact prevalence of renal dysfunction is not known. Reported prevalence from a few published studies is up to 38% and it is higher than that in age-matched control groups. Furthermore, in patients suffering from stroke renal dysfunction is associated with short and long term mortality. The most effective treatment of stroke in patients with CKD is not known and further studies are needed.

Causes of death in peritoneal dialysis patients with different kidney diseases and comorbidities: a retrospective clinical analysis in a Chinese center

OBJECTIVES

The objective of the study is to identify and compare the different causes of death among peritoneal dialysis (PD) patients varying in baseline characteristics, including gender, age, primary diseases, and comorbidities and to assess risk factors for first-year death.

METHODS

The clinical data of 179 PD patients who were regularly followed up in our hospital and died between January 2006 and February 2011 were retrospectively reviewed.

RESULTS

Median age at PD catheter implantation was 73 years. The most common primary diseases leading to ESRD were diabetic nephropathy (DN; 26.3 %), chronic glomerulonephritis (CGN; 24.6 %), and hypertensive nephropathy (HN; 21.8 %). The main causes of death in the DN and CGN groups were infections (42.6 %) and cardiocerebrovascular accidents (34.1 %), respectively. Patients with systemic vasculitis (SV) had the highest mortality rate from infection (71.4 %). Cox regression model showed that, compared with patients with CGN, those who had primary disease of DN, renal amyloidosis, multiple myeloma, or vasculitis were at higher risk of first-year death. Cerebrovascular disease, chronic heart failure, and/or lower serum albumin at baseline were also risk factors for first-year death.

CONCLUSIONS

The main causes of death in PD patients with DN and CGN were infections and cardiocerebrovascular accidents, respectively. Risk factors for first-year death included the primary diseases, cerebrovascular diseases, chronic heart failure, and lower serum albumin at baseline.

Stroke and the "stroke belt" in dialysis: contribution of patient characteristics to ischemic stroke rate and its geographic variation

Geographic variation in stroke rates is well established in the general population, with higher rates in the South than in other areas of the United States. ESRD is a potent risk factor for stroke, but whether regional variations in stroke risk exist among dialysis patients is unknown. Medicare claims from 2000 to 2005 were used to ascertain ischemic stroke events in a large cohort of 265,685 incident dialysis patients. A Poisson generalized linear mixed model was generated to determine factors associated with stroke and to ascertain state-by-state geographic variability in stroke rates by generating observed-to-expected (O/E) adjusted rate ratios for stroke. Older age, female sex, African American race and Hispanic ethnicity, unemployed status, diabetes, hypertension, history of stroke, and permanent atrial fibrillation were positively associated with ischemic stroke, whereas body mass index >30 kg/m(2) was inversely associated with stroke (P<0.001 for each). After full multivariable adjustment, the three states with O/E rate ratios >1.0 were all in the South: North Carolina, Mississippi, and Oklahoma. Regional efforts to increase primary prevention in the "stroke belt" or to better educate dialysis patients on the signs of stroke so that they may promptly seek care may improve stroke care and outcomes in dialysis patients.

Incidence of stroke before and after dialysis initiation in older patients

The incidence of stroke is substantially higher among hemodialysis patients than among patients with earlier stages of CKD, but to what extent the initiation of dialysis accelerates the risk for stroke is not well understood. In this cohort study, we analyzed data from incident hemodialysis and peritoneal dialysis patients in 2009 who were at least 67 years old and had Medicare as primary payer. We noted whether each of the 20,979 hemodialysis patients initiated dialysis as an outpatient (47%) or inpatient (53%). One year before initiation, the baseline stroke rate was 0.15%-0.20% of patients per month (ppm) for both outpatient and inpatient initiators. Among outpatient initiators, stroke rates began rising approximately 90 days before initiation, reached 0.5% ppm during the 30 days before initiation, and peaked at 0.7% ppm (8.4% per patient-year) during the 30 days after initiation. The pattern was similar among inpatient initiators, but the stroke rate peaked at 1.5% ppm (18% per patient-year). For both hemodialysis groups, stroke rates rapidly declined by 1-2 months after initiation, fluctuated, and stabilized at approximately twice the baseline rate by 1 year. Among the 620 peritoneal dialysis patients, stroke rates were slightly lower and variable, but approximately doubled after initiation. In conclusion, these data suggest that the process of initiating dialysis may cause strokes. Further studies should evaluate methods to mitigate the risk for stroke during this high-risk period.

Low serum fetuin A levels and incident stroke in patients with maintenance haemodialysis

BACKGROUND AND OBJECTIVES

Fetuin A, a predictor of mortality in dialysis patients, is associated with vascular calcification and atherosclerosis in haemodialysis (HD) patients. Whether it predicts stroke remains unknown. This study aimed to investigate the association between fetuin A and incident stoke in maintenance HD patients.

DESIGN, SETTING, PARTICIPANTS AND MEASUREMENTS

This is a prospective observational study. 238 prevalent HD patients (127 women and 111 men; mean age, 60 ± 12 years) were followed up for the occurrence of stroke for 55 months. Baseline circulating fetuin A levels, biochemical data and other markers of inflammation were measured. The major outcome was the occurrence of incident ischaemic or haemorrhagic stroke.

RESULTS

Thirty one patients had incident strokes; an incidence of 38·4/1000 patient-years (95% confidence interval (CI) 36·5-39·8/1000 patient-years) on follow-up. Patients in the lowest tertile of fetuin A concentration had highest risk to have incident stroke (P < 0·001, log-rank test). By Cox proportional-hazards regression, patients with higher fetuin A levels experienced lower incidence of stroke, hazard ratio (HR) of 0·89 (95% CI, 0·84-0·96), while those with higher mean arterial blood pressure had an HR of 1·19 (95% CI, 1·07-1·34) and those with higher calcium phosphate product (CaxP) had an HR of 1·39 (95% CI, 1·1-1·73) for having strokes. For patients without previous history of diabetes and cerebrovascular disease, fetuin A deficiency also predicts the occurrence of incident stroke.

CONCLUSIONS

Fetuin A deficiency is associated with a higher risk of incident stroke among prevalent HD patients.

Atrial fibrillation and risk of stroke in dialysis patients

PURPOSE

Both stroke and chronic atrial fibrillation (AF) are common in dialysis patients, but uncertainty exists in the incidence of new strokes and the risk conferred by chronic AF.

METHODS

A cohort of dually eligible (Medicare and Medicaid) incident dialysis patients was constructed. Medicare claims were used to determine the onset of chronic AF, which was specifically treated as a time-dependent covariate. Cox proportional hazards models were used to model time to stroke.

RESULTS

Of 56,734 patients studied, 5629 (9.9%) developed chronic AF. There were 22.8 ischemic and 5.0 hemorrhagic strokes per 1000 patient-years, a ratio of approximately 4.5:1. Chronic AF was independently associated with time to ischemic (hazard ratio [HR], 1.26; 99% confidence interval [CI], 1.06-1.49; P = .0005), but not hemorrhagic, stroke. Race was strongly associated with hemorrhagic stroke: African Americans (HR, 1.46; 99% CI, 1.08-1.96), Hispanics (HR, 1.64; 99% CI, 1.16-2.31), and others (HR, 1.76; 99% CI, 1.16-2.78) had higher rates than did Caucasians (all P < .001).

CONCLUSIONS

Chronic AF has a significant, but modest, association with ischemic stroke. Race/ethnicity is strongly associated with hemorrhagic strokes. The proportion of strokes owing to hemorrhage is much higher than in the general population.

Anticoagulants, renal failure and atrial fibrillation

The prevalence of atrial fibrillation (AF) in patients with chronic renal failure (CRF) and end-stage renal disease (ESRD) is very high and also in this population AF is associated with an increased risk of stroke. Warfarin is the treatment of choice for AF to prevent thromboembolic events, but it has been reported that its use in CRF and hemodialysis (HD) patients is associated with an increased risk of bleeding compared with patients with normal renal function. Moreover, historical studies suggest that warfarin increases the incidence of both ischemic and hemorrhagic strokes in HD patients. However, a clear benefit:risk ratio against warfarin in patients with CRF or ESRD and AF has not been demonstrated. New oral anticoagulants, thrombin or factor Xa inhibitors, are now available. Patients with severe CRF (i.e., glomerular filtration rate < 30 mL/min) and with ESRD, however, were excluded from the trials that have established their efficacy and safety. The advent of new oral anticoagulants raises the important question if patients with severe CRF and ESRD should be excluded or not from this new therapeutic opportunity.