Chronic kidney disease and risk of death during hospitalization for stroke

Personalized prediction of mortality in patients with acute ischemic stroke using explainable artificial intelligence

BACKGROUND

Research into the acute kidney disease (AKD) after acute ischemic stroke (AIS) is rare, and how clinical features influence its prognosis remain unknown. We aim to employ interpretable machine learning (ML) models to study AIS and clarify its decision-making process in identifying the risk of mortality.

METHODS

We conducted a retrospective cohort study involving AIS patients from January 2020 to June 2021. Patient data were randomly divided into training and test sets. Eight ML algorithms were employed to construct predictive models for mortality. The performance of the best model was evaluated using various metrics. Furthermore, we created an artificial intelligence (AI)-driven web application that leveraged the top ten most crucial features for mortality prediction.

RESULTS

The study cohort consisted of 1633 AIS patients, among whom 257 (15.74%) developed subacute AKD, 173 (10.59%) experienced AKI recovery, and 65 (3.98%) met criteria for both AKI and AKD. The mortality rate stood at 4.84%. The LightGBM model displayed superior performance, boasting an AUROC of 0.96 for mortality prediction. The top five features linked to mortality were ACEI/ARE, renal function trajectories, neutrophil count, diuretics, and serum creatinine. Moreover, we designed a web application using the LightGBM model to estimate mortality risk.

CONCLUSIONS

Complete renal function trajectories, including AKI and AKD, are vital for fitting mortality in AIS patients. An interpretable ML model effectively clarified its decision-making process for identifying AIS patients at risk of mortality. The AI-driven web application has the potential to contribute to the development of personalized early mortality prevention.

Association of chronic kidney disease with outcomes in acute stroke

Previous studies have found an association between chronic kidney disease and poor outcomes in stroke patients. However, there is a paucity of literature evaluating this association by stroke type. We therefore aimed to explore the association between CKD and stroke outcomes according to type of stroke. The data consisting of 594,681 stroke patients were acquired from Universal Coverage Health Security Insurance Scheme Database in Thailand. Binary logistic regression was used to assess the relationship of CKD and outcomes, which were as follows; in-hospital mortality, long length of stay (>3 days), pneumonia, sepsis, respiratory failure and myocardial infarction. Results: after fully adjusting for covariates, CKD was associated with increased odds of in-hospital mortality in patients with ischemic (OR 1.32; 95% CI = 1.27–1.38), haemorrhagic (OR 1.31; 95% CI = 1.24–1.39), and other undetermined stroke type (OR 1.44; 95% CI = 1.21–1.73). CKD was found to be associated with increased odds of pneumonia, sepsis, respiratory failure and myocardial infarction in ischaemic stroke. While CKD was found to be associated with increase odds of sepsis, respiratory failure, and myocardial infarction, decrease odds of pneumonia was observed in patients with haemorrhagic stroke. In other undetermined stroke type, CKD was found to only be associated with increase odds of sepsis and respiratory failure, while there is no significant association of CKD and increase or decrease odds with pneumonia and myocardial infarction. CKD was associated with poor outcomes in all stroke types. CKD should be considered as part of stroke prognosis as well as identifying at risk patient population for in-hospital complications.

Chronic and End-Stage Kidney Disease in the Neurological Intensive Care Unit

Patients with renal disease have increased rates of admission to the neurological intensive care unit related to overlapping risk factors for renal and cerebrovascular disease as well as unique risks associated with renal dysfunction alone. Management of acute neurological injury in these patients requires individualized attention to diagnostic and management factors as they relate to coagulopathy, disorders of immune function, encephalopathy and renal replacement modalities. Careful consideration of these brain-kidney interactions is necessary to optimize care for this special patient population and improve neurological and renal outcomes.

Lack of impact of polycystic kidney disease on the outcome of aneurysmal subarachnoid hemorrhage: a matched case-control study

OBJECTIVE

The authors set out to study whether autosomal dominant polycystic kidney disease (ADPKD), an established risk factor for intracranial aneurysms (IAs), affects the acute course and long-term outcome of aneurysmal subarachnoid hemorrhage (aSAH).

METHODS

The outcomes of 32 ADPKD patients with aSAH between 1980 and 2015 (median age 43 years; 50% women) were compared with 160 matched (age, sex, and year of aSAH) non-ADPKD aSAH patients in the prospectively collected Kuopio Intracranial Aneurysm Patient and Family Database.

RESULTS

At 12 months, 75% of the aSAH patients with ADPKD versus 71% of the matched-control aSAH patients without ADPKD had good outcomes (Glasgow Outcome Scale score 4 or 5). There was no significant difference in condition at admission. Hypertension had been diagnosed before aSAH in 69% of the ADPKD patients versus 27% of controls (p < 0.001). Multiple IAs were present in 44% of patients in the ADPKD group versus 25% in the control group (p = 0.03). The most common sites of ruptured IAs were the anterior communicating artery (47% vs 29%, p = 0.05) and the middle cerebral artery bifurcation (28% vs 31%), and the median size was 6.0 mm versus 8.0 mm (p = 0.02). During the median follow-up of 11 years, a second aSAH occurred in 3 of 29 (10%) ADPKD patients and in 4 of 131 (3%) controls (p = 0.11). A fatal second aSAH due to a confirmed de novo aneurysm occurred in 2 (6%) of the ADPKD patients but in none of the controls (p = 0.027).

CONCLUSIONS

The outcomes of ADPKD patients with aSAH did not differ significantly from those of matched non-ADPKD aSAH patients. ADPKD patients had an increased risk of second aSAH from a de novo aneurysm, warranting long-term angiographic follow-up.

A systematic review and external validation of stroke prediction models demonstrates poor performance in dialysis patients

OBJECTIVES

The objective of this study was to systematically review and externally assess the predictive performance of models for ischemic stroke in incident dialysis patients.

STUDY DESIGN AND SETTING

Two reviewers systematically searched and selected ischemic stroke models. Risk of bias was assessed with the PROBAST. Predictive performance was evaluated within The Netherlands Cooperative Study on the Adequacy of Dialysis (NECOSAD), a large prospective multicenter cohort of incident dialysis patients. For discrimination, c-statistics were calculated; calibration was assessed by plotting predicted and observed probabilities for stroke, and calibration-in-the-large.

RESULTS

Seventy-seven prediction models for stroke were identified, of which 15 were validated. Risk of bias was high, with all of these models scoring high risk in one or more domains. In NECOSAD, of the 1,955 patients, 127 (6.5%) suffered an ischemic stroke during the follow-up of 2.5 years. Compared with the original studies, most models performed worse with all models showing poor calibration and discriminative abilities (c-statistics ranging from 0.49 to 0.66). The Framingham showed reasonable calibration; however, with a c-statistic of 0.57 (95% CI 0.50-0.63), the discrimination was poor.

CONCLUSION

This external validation demonstrates the weak predictive performance of ischemic stroke models in incident dialysis patients. Instead of using these models in this fragile population, either existing models should be updated, or novel models should be developed and validated.

Chronic Kidney Disease and Outcome Following Endovascular Thrombectomy for Acute Ischemic Stroke

BACKGROUND AND OBJECTIVES

Chronic kidney disease (CKD) is present in 20% to 35% of acute ischemic stroke patients and may increase the risk of poor functional outcome or death. We aimed to determine whether CKD was associated with worse outcome in stroke patients treated with endovascular thrombectomy (EVT).

DESIGN, SETTING, PARTICIPANTS, AND MEASUREMENTS

Consecutive EVT patients were identified from a prospective registry and dichotomized into patients with and without CKD, defined as an eGFR of less than 60 mL/min/1.73m². The primary outcome was 3-month mortality following EVT. Secondary outcomes included symptomatic intracerebral hemorrhage (defined by the Safe Implementation of Thrombolysis in Stroke-Monitoring Study), early neurological recovery (defined as change in National Institutes of Health Stroke Scale [NIHSS] score of ≥8 at 24 hours or an NIHSS of 0-1 at 24 hours) and functional independence (defined as a modified Rankin Scale [mRS] score of 0, 1 or 2) at 3 months.

RESULTS

378 EVT patients (223 men; mean ± SD age 65 ± 15 years) were included. The median (IQR) admission eGFR was 71 (58-89) mL/min/1.73 m² and 117 (31%) patients had CKD. Multiple logistic regression adjusted for potential confounders demonstrated that CKD was a significant predictor of lower rates of functional independence (OR = .54, 95% CI, .31 to .90, P = .02), higher mRS scores (common OR = 1.78, 95% CI, 1.14 to 2.81, P = .01), and increased mortality (OR = 2.19, 95% CI, 1.16 to 4.12, P = .01). There was no association between CKD and early neurological recovery (OR = .92, 95% CI, .55 to 1.49, P = .71) or symptomatic intracerebral hemorrhage (OR = 1.18, 95% CI, .38 to 3.69, P = .77).

CONCLUSIONS

CKD was a significant predictor of worse functional outcome and mortality in stroke patients treated with EVT. The presence of CKD should not preclude patients from proceeding to EVT, but may help with prognostication and improve shared decision-making between patients, families and physicians.

New determinants for casual peripheral mechanism of neurogenic lung edema in subarachnoid hemorrhage due to ischemic degeneration of vagal nerve, kidney and lung circuitry. Experimental study1

Purpose

To evaluate whether there is a relationship between renal artery vasospasm related low glomerular density or degeneration and neurogenic lung edema (NLE) following subarachnoid hemorrhage.

Methods

This study was conducted on 26 rabbits. A control group was formed of five animals, a SHAM group of 5 to which saline and a study group (n=16) injected with homologous blood into the sylvian cisterna. Numbers of degenerated axons of renal branches of vagal nerves, atrophic glomerulus numbers and NLE scores were recorded.

Results

Important vagal degeneration, severe renal artery vasospasm, intrarenal hemorrhage and glomerular atrophy observed in high score NLE detected animals. The mean degenerated axon density of vagal nerves (n/mm²), atrophic glomerulus density (n/mm³) and NLE scores of control, SHAM and study groups were estimated as 2.40±1.82, 2.20±1.30, 1.80±1.10, 8.00±2.24, 8.80±2.39, 4.40±1.14 and 154.38±13.61, 34.69±2.68 and 12.19±1.97 consecutively. Degenerated vagal axon, atrophic glomerulus and NLE scores are higher in study group than other groups and the differences are statistically meaningful (p<0.001).

Conclusion

Vagal complex degeneration based glomerular atrophy have important roles on NLE following SAH which has not been extensively mentioned in the literature.

Temporal Trends in the Outcomes of Dialysis Patients Admitted With Acute Ischemic Stroke

BACKGROUND

There is a paucity of contemporary data on the characteristics and outcomes of acute ischemic stroke (AIS) in patients on maintenance dialysis.

METHODS AND RESULTS

We used the nationwide inpatient sample to examine contemporary trends in the incidence, management patterns, and outcomes of AIS in dialysis patients. A total of 930 010 patients were admitted with AIS between 2003 and 2014, of whom 13 642 (1.5%) were on dialysis. Overall, the incidence of AIS among dialysis patients decreased significantly (Ptrend<0.001), while it remained stable in non-dialysis patients (Ptrend=0.78). Compared with non-dialysis patients, those on dialysis were younger (67±13 years versus 71±15 years, P<0.001), and had higher prevalence of major comorbidities. Black patients constituted 35.2% of dialysis patients admitted with AIS compared with 16.7% of patients in the non-dialysis group (P<0.001). After propensity score matching, in-hospital mortality was higher in the dialysis group (7.6% versus 5.2%, P<0.001), but this mortality gap narrowed overtime (Ptrend<0.001). Hemorrhagic conversion and gastrointestinal bleeding rates were similar, but blood transfusion was more common in the dialysis group. Rates of severe disability surrogates (tracheostomy, gastrostomy, mechanical ventilation and non-home discharge) were also similar in both groups. However, dialysis patients had longer hospitalizations, and accrued a 25% higher total cost of acute care.

CONCLUSIONS

Dialysis patients have 8-folds higher incidence of AIS compared withnon-dialysis patients. They also have higher risk-adjusted in-hospital mortality, sepsis and blood transfusion, longer hospitalizations, and higher cost. There is a need to identify preventative strategies to reduce the risk of AIS in the dialysis population.

Newer glomerular filtration rate estimating equations for the full age spectrum based on serum creatinine and cystatin C in predicting mortality in patients with ischemic stroke

BACKGROUND

Renal dysfunction is associated with increased risk of mortality. The novel Full Age Spectrum (FAS) equations estimating the glomerular filtration rate (GFR) based on serum creatinine (FAScrea) and cystatin C (FAScysC) are validated across the entire age spectrum and are superior markers of renal function compared to other equations. Possible association of these equations with mortality in patients with ischemic stroke is not known.

PATIENTS AND METHODS

We included 390 patients (207 men, 183 women) in our observational cohort study who had suffered from an ischemic stroke and followed-up on for 3 years. Serum creatinine and cystatin C were measured at admission; GFR was estimated according to the FAScrea, CKD-EPIcrea, FAScysC and CKD-EPIcysC equations. The values of estimated GFRs were divided into quintiles.

RESULTS

During the follow-up period, 173 (44.4%) patients died. The association of hazard ratios for FAScrea and CKD-EPIcrea with all-cause mortality was J-shaped and only significantly higher when comparing the fifth quintile hazard ratio for mortality with the first quintile (P < 0.001). For FAScysC and CKD-EPIcysC, hazard ratios increased from the first to the fifth quintile linearly. In an adjusted analysis, FAScrea and CKD-EPIcrea were not associated with all-cause mortality and the hazard ratios of the fifth quintile of FAScysC (P = 0.008) and CKD-EPIcysC (P = 0.042) were significantly associated with mortality compared to the first quintile.

CONCLUSIONS

In patients with an ischemic stroke, estimated GFR based on serum cystatin (FAScysC and CKD-EPIcysC) was a better predictor of all-cause and cardiovascular mortality than estimated GFR based on serum creatinine.

Increasing prevalence of vascular risk factors in patients with stroke: A call to action

OBJECTIVE

To evaluate trends in prevalence of cardiovascular risk factors (hypertension, diabetes, dyslipidemia, smoking, and drug abuse) and cardiovascular diseases (carotid stenosis, chronic renal failure [CRF], and coronary artery disease [CAD]) in acute ischemic stroke (AIS) in the United States.

METHODS

We used the 2004-2014 National Inpatient Sample to compute weighted prevalence of each risk factor in hospitalized patients with AIS and used joinpoint regression to evaluate change in prevalence over time.

RESULTS

Across the 2004-2014 period, 92.5% of patients with AIS had ≥1 risk factor. Overall age- and sex-adjusted prevalence of hypertension, diabetes, dyslipidemia, smoking, and drug abuse were 79%, 34%, 47%, 15%, and 2%, respectively, while those of carotid stenosis, CRF, and CAD were 13%, 12%, and 27%, respectively. Risk factor prevalence varied by age (hypertension: 44% in 18-39 years vs 82% in 60-79 years), race (diabetes: Hispanic 49% vs white 30%), and sex (drug abuse: men 3% vs women 1.4%). Using joinpoint regression, prevalence of hypertension increased annually by 1.4%, diabetes by 2%, dyslipidemia by 7%, smoking by 5%, and drug abuse by 7%. Prevalence of CRF, carotid stenosis, and CAD increased annually by 13%, 6%, and 1%, respectively. Proportion of patients with multiple risk factors also increased over time.

CONCLUSIONS

Despite numerous guidelines and prevention initiatives, prevalence of hypertension, diabetes, dyslipidemia, smoking, and drug abuse in AIS increased across the 2004-2014 period. Proportion of patients with carotid stenosis, CRF, and multiple risk factors also increased. Enhanced risk factor modification strategies and implementation of evidence-based recommendations are needed for optimal stroke prevention.

Effects of stroke on changes in heart rate variability during hemodialysis

Background

Stroke and low heart rate variability (HRV) are both associated with an unfavorable prognosis in hemodialysis patients. The relationship between stroke and changes in HRV during hemodialysis remains unclear.

Methods

This study measured differences between predialysis and postdialysis HRV (△HRV) in 182 maintenance hemodialysis patients, including 30 patients with stroke, to assess changes in HRV during hemodialysis, and also to compare results to 114 healthy controls.

Results

All predialysis HRV measurements had no differences between stroke patients and those without stroke, but were lower than healthy controls. Postdialysis very low frequency (VLF) (P < 0.001), low frequency (LF) (P = 0.001), total power (TP) (P < 0.001) and the LF/high frequency (HF) ratio (P < 0.001) increased significantly relative to predialysis values in patients without stroke, whereas postdialysis HRV did not increase in stroke patients. After multivariate adjustment, dialysis vintage was negatively associated with △VLF (β = -0.698, P = 0.046), △LF (β = -0.931, P = 0.009), and △TP (β = -0.887, P = 0.012) in patients without stroke. Serum intact parathyroid hormone (β = -0.707, P = 0.019) was negatively associated with △LF. Total cholesterol (β = -0.008, P = 0.001) and high sensitivity C-reactive protein (β = -0.474, P = 0.012) were inversely correlated with the △LF/HF ratio in patients without stroke.

Conclusion

HRV in hemodialysis patients is lower than in the general population. Increase in △HRV was observed in hemodialysis patients without stroke but not in stroke patients. This result suggests suppressed autonomic nervous reactions against volume unloading during hemodialysis, which might contribute to unfavorable outcomes in hemodialysis patients but even more so in those with prior stroke. Nephrologists should notice the importance of △HRV especially in high-risk patients.

Relationship between history of coronary heart disease at dialysis initiation and onset of events associated with heart disease: a propensity-matched analysis of a prospective cohort study

Background

Chronic kidney disease (CKD) is an independent risk factor for cardiovascular disease (CVD) events, and a number of reports have shown a relationship between CKD and CVD in pre-dialysis or maintenance dialysis patients. However, few studies have reported serial observations during dialysis initiation and maintenance. Therefore, we examined whether the incidence of heart disease events differed between CKD patients with and without a history of coronary heart disease (CHD) at dialysis initiation.

Methods

The subjects were patients in the 17 centers participating in the Aichi Cohort Study of Prognosis in Patients Newly Initiated into Dialysis (AICOPP) from October 2011 to September 2013. We excluded nine patients whose outcomes were unknown, as determined by a survey conducted at the end of March 2015. Thus, we enrolled 1,515 subjects into the study. We classified patients into 2 groups according to the history of CHD (i.e., a CHD group and a non-CHD group). Propensity scores (PS) represented the probability of being assigned to a group with or without a history of CHD. Onset of heart disease events and associated mortality and all-cause mortality were compared in PS-matched patients by using the log-rank test for Kaplan-Meier curves. Factors contributing to heart disease events were examined using stepwise multivariate Cox proportional hazards analysis.

Results

There were 254 patients in each group after PS-matching. During observation, heart disease events occurred in 85 patients (33.5%) in the CHD group and 48 (18.9%) patients in the non-CHD group. The incidence was significantly higher in the CHD group (p < 0.0001). The CHD group was associated with higher incidence of heart disease events (vs. the non-CHD group, hazard ratio = 1.750, 95% confidence interval = 1.160–2.639). In addition, comorbidities such as diabetes mellitus, low body mass index, and low serum high-density lipoprotein cholesterol were associated with higher incidence of events.

Conclusion

History of CHD at dialysis initiation was associated with a higher incidence of heart disease events and mortality and all-cause mortality.

Trial registration

UMIN 000007096. Registered 18 January 2012.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-017-0495-8) contains supplementary material, which is available to authorized users.

Renal Dysfunction Is Associated With Poststroke Discharge Disposition and In-Hospital Mortality: Findings From Get With The Guidelines-Stroke

BACKGROUND AND PURPOSE

Kidney disease is a frequent comorbidity in patients presenting with acute ischemic stroke. We evaluated whether the estimated glomerular filtration rate (eGFR) on admission is associated with poststroke in-hospital mortality or discharge disposition.

METHODS

In this cohort study, data from ischemic stroke patients in Get With The Guidelines-Stroke linked to fee-for-service Medicare data were analyzed. The Modification of Diet in Renal Disease study equation was used to calculate the eGFR (mL/min/1.73 m²). Dialysis was identified by International Classification of Diseases, Ninth Revision codes. Adjusted multivariable Cox proportional hazards models were used to determine the independent associations of eGFR with discharge disposition and in-hospital mortality. Adjusted individual models also examined whether the association of clinical and demographic factors with outcomes varied by eGFR level.

RESULTS

Of 232 236 patients, 47.3% had an eGFR ≥60, 26.6% an eGFR 45 to 59, 16.8% an eGFR 30 to 44, 5.6% an eGFR 15 to 29, 0.7% an eGFR<15 without dialysis, and 2.8% were receiving dialysis. Of the total cohort, 11.8% died during the hospitalization or were discharged to hospice, and 38.6% were discharged home. After adjusting for other relevant variables, renal dysfunction was independently associated with an increased risk of in-hospital mortality that was highest among those with eGFR <15 without dialysis (odds ratio, 2.52; 95% confidence interval, 2.07-3.07). An eGFR 15 to 29 (odds ratio, 0.82; 95% confidence interval, 0.78-0.87), eGFR <15 (odds ratio, 0.72; 95% confidence interval, 0.61-0.86), and dialysis (odds ratio, 0.86; 95% confidence interval, 0.79-0.94) remained associated with lower odds of being discharged home. In addition, the associations of several clinical and demographic factors with outcomes varied by eGFR level.

CONCLUSIONS

eGFR on admission is an important predictor of poststroke short-term outcomes.

Mortality and treatment costs of hospitalized chronic kidney disease patients between the three major health insurance schemes in Thailand

Background

Thailand has reformed its healthcare to ensure fairness and universality. Previous reports comparing the fairness among the 3 main healthcare schemes, including the Universal Coverage Scheme (UCS), the Civil Servant Medical Benefit Scheme (CSMBS) and the Social Health Insurance (SHI) have been published. They focused mainly on provision of medication for cancers and human immunodeficiency virus infection. Since chronic kidney disease (CKD) patients have a high rate of hospitalization and high risk of death, they also require special care and need more than access to medicine. We, therefore, performed a 1-year, nationwide, evaluation on the clinical outcomes (i.e., mortality rates and complication rates) and treatment costs for hospitalized CKD patients across the 3 main health insurance schemes.

Methods

All adult in-patient CKD medical expense forms in fiscal 2010 were analyzed. The outcomes focused on were clinical outcomes, access to special care and equipment (especially dialysis), and expenses on CKD patients. Factors influencing mortality rates were evaluated by multiple logistic regression.

Results

There were 128,338 CKD patients, accounting for 236,439 admissions. The CSMBS group was older on average, had the most severe co-morbidities, and had the highest hospital charges, while the UCS group had the highest rate of complications. The mortality rates differed among the 3 insurance schemes; the crude odds ratio (OR) for mortality was highest in the CSMBS scheme. After adjustment for biological, economic, and geographic variables, the UCS group had the highest risk of in-hospital death (OR 1.13;95 % confidence interval (CI) 1.07–1.20; p < 0.001) while the SHI group had lowest mortality (OR 0.87; 95 % CI 0.76–0.99; p = 0.038). The circumscribed healthcare benefits and limited access to specialists and dialysis care in the UCS may account for less favorable comparison with the CSMBS and SHI groups.

Conclusions

Significant differences are observed in mortality rates among CKD patients from among the 3 main healthcare schemes. Improvements in equity of care might minimize the differences.

Electronic supplementary material

The online version of this article (doi:10.1186/s12913-016-1792-9) contains supplementary material, which is available to authorized users.

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.

Neurological complications in chronic kidney disease patients

Chronic kidney disease (CKD) is associated with a high prevalence of cerebrovascular disorders such as stroke, white matter diseases, intracerebral microbleeds and cognitive impairment. This situation has been observed not only in end-stage renal disease patients but also in patients with mild or moderate CKD. The occurrence of cerebrovascular disorders may be linked to the presence of traditional and non-traditional cardiovascular risk factors in CKD. Here, we review current knowledge on the epidemiological aspects of CKD-associated neurological and cognitive disorders and discuss putative causes and potential treatment. CKD is associated with traditional (hypertension, hypercholesterolaemia, diabetes etc.) and non-traditional cardiovascular risk factors such as elevated levels of oxidative stress, chronic inflammation, endothelial dysfunction, vascular calcification, anaemia and uraemic toxins. Clinical and animal studies indicate that these factors may modify the incidence and/or outcomes of stroke and are associated with white matter diseases and cognitive impairment. However, direct evidence in CKD patients is still lacking. A better understanding of the factors responsible for the elevated prevalence of cerebrovascular diseases in CKD patients may facilitate the development of novel treatments. Very few clinical trials have actually been performed in CKD patients, and the impact of certain treatments is subject to debate. Treatments that lower LDL cholesterol or blood pressure may reduce the incidence of cerebrovascular diseases in CKD patients, whereas treatment with erythropoiesis-stimulating agents may be associated with an increased risk of stroke but a decreased risk of cognitive disorders. The impact of therapeutic approaches that reduce levels of uraemic toxins has yet to be evaluated.

Proteinuria, but Not eGFR, Predicts Stroke Risk in Chronic Kidney Disease: Chronic Renal Insufficiency Cohort Study

BACKGROUND AND PURPOSE

Chronic kidney disease is associated with an increased risk of cardiovascular events. However, the impact of chronic kidney disease on cerebrovascular disease is less well understood. We hypothesized that renal function severity would be predictive of stroke risk, independent of other vascular risk factors.

METHODS

The study population included 3939 subjects enrolled in the Chronic Renal Insufficiency Cohort (CRIC) study, a prospective observational cohort. Stroke events were reported by participants and adjudicated by 2 vascular neurologists. Cox proportional hazard models were used to compare measures of baseline renal function with stroke events. Multivariable analysis was performed to adjust for key covariates.

RESULTS

In 3939 subjects, 143 new stroke events (0.62 events per 100 person-years) occurred over a mean follow-up of 6.4 years. Stroke risk was increased in subjects who had worse baseline measurements of renal function (estimated glomerular filtration rate and total proteinuria or albuminuria). When adjusted for variables known to influence stroke risk, total proteinuria or albuminuria, but not estimated glomerular filtration rate, were associated with an increased risk of stroke. Treatment with blockers of the renin-angiotensin system did not decrease stroke risk in individuals with albuminuria.

CONCLUSIONS

Proteinuria and albuminuria are better predictors of stroke risk in patients with chronic kidney disease than estimated glomerular filtration rate. The impact of therapies targeting proteinuria/albuminuria in individuals with chronic kidney disease on stroke prevention warrants further investigation.

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.

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.

Patterns of care quality and prognosis among hospitalized ischemic stroke patients with chronic kidney disease

Background

Relatively little is known about the quality of care and outcomes for hospitalized ischemic stroke patients with chronic kidney disease (CKD). We examined quality of care and in‐hospital prognoses among patients with CKD in the Get With The Guidelines–Stroke (GWTG‐Stroke) program

Methods and Results

We analyzed 679 827 patients hospitalized with ischemic stroke from 1564 US centers participating in the GWTG‐Stroke program between January 2009 and December 2012. Use of 7 predefined ischemic stroke performance measures, composite “defect‐free” care compliance, and in‐hospital mortality were examined based on glomerular filtration rate (GFR) categorized as a dichotomous (+CKD as <60) or rank‐ordered variable: normal (≥90), mild (≥60 to <90), moderate (≥30 to <60), severe (≥15 to <30), and kidney failure (<15 or dialysis). There were 236 662 (35%) ischemic stroke patients with CKD. Patients with severe renal dysfunction or failure were significantly less likely to receive guideline‐based therapies. Compared with patients with normal kidney function (≥90), those with CKD (adjusted OR 0.91 [95% CI: 0.89 to 0.92]), moderate dysfunction (adjusted OR 0.94 [95% CI: 0.92 to 0.97]), severe dysfunction (adjusted OR 0.80 [95% CI: 0.77 to 0.84]), or failure (adjusted OR 0.72 [95% CI: 0.68 to 0.0.76]), were less likely to receive 100% defect‐free care measure compliance. Inpatient mortality was higher for patients with CKD (adjusted odds ratio 1.44 [95% CI: 1.40 to 1.47]), and progressively rose with more severe renal dysfunction.

Conclusions

Despite higher in‐hospital mortality rates, ischemic stroke patients with CKD, especially those with greater severity of renal dysfunction, were less likely to receive important guideline‐recommended therapies.

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.

Clinical outcomes of intracerebral hemorrhage in hemodialysis patients

BACKGROUND

Chronic renal failure (CRF) is associated with a high incidence of stroke. In particular, the mortality rate for intracerebral hemorrhage (ICH) patients with hemodialysis (HD) due to advanced stage CRF is high, and the annual number of such cases is increasing. Therefore, we retrospectively investigated 5 years of clinical data from patients with ICH in our institution to reveal differences in the clinical courses of HD and non-HD patients and to identify risk factors for poor outcomes in ICH patients with HD.

METHODS

Three hundred sixty-six consecutive patients with nontraumatic spontaneous ICH, 91% of whom did not receive HD (non-HD group) and 9% of whom received HD for the treatment of CRF (HD group), were enrolled. Clinical data, including the presence of intraventricular hemorrhage (IVH), microbleeds, modified Rankin scale scores, previous medical disease history, the presence of HD, and the days on which ICH occurred, were evaluated.

RESULTS

In a comparison of HD patients and non-HD patients, the HD patients had higher rates of hematomas in the basal ganglia, IVH, use of antihypertensive drugs, antidiabetic drugs, and antiplatelet/anticoagulants. The mortality rate was higher in the HD group (44%) than in the non-HD group (21%). In the HD group, the risk factors associated with mortality were hematoma volume, the presence of IVH, and lack of antihypertensive drug use. Eighty-five percent of the ICH occurred on intermittent HD days or before the HD procedure on an HD day.

CONCLUSIONS

Mortality in ICH patients with HD was associated with lack of antihypertensive drug use. Therefore, strict control of blood pressure is needed in HD patients to prevent ICH, especially on intermittent HD days or before the HD procedure.

Association of renal biomarkers with 3-month and 1-year outcomes among critically ill acute stroke patients

Background

The comparative relationships of widely recognized biomarkers of renal injury with short-term and long-term outcomes among critically ill acute stroke patients are unknown. We evaluated the impact of baseline albuminuria [urine albumin-creatinine ratio (UACR)≥30 mg/g] or low estimated glomerular filtration rate (eGFR<60 ml/min per 1.73 m²) on stroke patients admitted to the intensive care unit (ICU).

Methods

We reviewed data on consecutive stroke patients admitted to a hospital ICU in Taiwan from September 2007 to August 2010 and followed-up for 1 year. Baseline UACR was categorized into <30 mg/g (normal), 30–299 mg/g (microalbuminuria), and ≥300 mg/g (macroalbuminuria), while eGFR was divided into ≥60, 45–59, and <45 ml/min per 1.73 m². The outcome measure was death or disability at 3-month and 1-year after stroke onset, assessed by dichotomizing the modified Rankin Scale at 3–6 versus 0–2.

Results

Of 184 consecutive patients, 153 (83%) met study entry criteria. Mean age was 67.9 years and median admission NIHSS score was 16. Among the renal biomarkers, only macroalbuminuria was associated with poorer 3-month outcome (OR 8.44, 95% CI 1.38 to 51.74, P = 0.021) and 1-year outcome (OR 18.06, 95% CI 2.59 to 125.94, P = 0.003) after adjustment of relevant covariates. When ischemic and hemorrhagic stroke were analyzed separately, macroalbuminuria was associated with poorer 1-year outcome among ischemic (OR 17.10, 95% CI 1.04 to 280.07, P = 0.047) and hemorrhagic stroke patients (OR 1951.57, 95% CI 1.07 to 3561662.85, P = 0.048), respectively, after adjustment of relevant covariates and hematoma volume.

Conclusions

Presence of macroalbuminuria indicates poor 3-month and 1-year outcomes among critically ill acute stroke patients.