Impact of proteinuria and glomerular filtration rate on risk of ischaemic and intracerebral hemorrhagic stroke: a result from the Kailuan study

Kidney disease and stroke: epidemiology and potential mechanisms of susceptibility

Patients with chronic kidney disease (CKD) have an increased risk of both ischaemic and haemorrhagic stroke compared with the general population. Both acute and chronic kidney impairment are independently associated with poor outcome after the onset of a stroke, after adjustment for confounders. End-stage kidney disease (ESKD) is associated with a 7- and 9-fold increased incidence of both ischaemic and haemorrhagic strokes, respectively, poorer neurological outcome and a 3-fold higher mortality. Acute kidney injury (AKI) occurs in 12% of patients with stroke and is associated with a 4-fold increased mortality and unfavourable functional outcome. CKD patients seem to have less access to revascularisation techniques like thrombolysis and thrombectomy despite their poorer prognosis. Even if CKD patients could benefit from these specific treatments in acute ischaemic stroke, their prognosis remains poor. After thrombolysis, CKD is associated with a 40% increased risk of intracerebral haemorrhage (ICH), a 20% increase in mortality and poorer functional neurological outcomes. After thrombectomy, CKD is not associated with ICH but is still associated with increased mortality, and AKI with unfavourable outcome and mortality. The beneficial impact of gliflozins on the prevention of stroke is still uncertain. Non-traditional risk factors of stroke, like uraemic toxins, can lead to chronic cerebrovascular disease predisposing to stroke in CKD, notably through an increase in the blood-brain barrier permeability and impaired coagulation and thrombosis mechanisms. Preclinical and clinical studies are needed to specifically assess the impact of these non-traditional risk factors on stroke incidence and outcomes, aiming to optimize and identify potential therapeutic targets.

Effects of estimated glomerular filtration rate on clinical outcomes in patients with intracerebral hemorrhage

BACKGROUND

The influence of chronic kidney disease (CKD) on the severity and prognosis of spontaneous intracerebral hemorrhage (ICH) has been scarcely investigated. We aimed to explore the association of admission estimated glomerular filtration rate (eGFR) levels with hemorrhagic stroke severity and outcomes in ICH patients.

MATERIALS AND METHODS

The patients enrolled in this study were from the China Stroke Center Alliance study (CSCA). Patients were divided into four groups according to differences in eGFR at admission (≥90; 60-89; 45-59; < 45). Multivariable logistic regression analysis was used to determine the association of the eGFR at admission with hemorrhagic stroke severity, in-hospital complications, discharge disposition, and in-hospital mortality after ICH.

RESULTS

A total of 85,167 patients with acute ICH were included in the analysis. Among them, 9493 (11.1%) had a baseline eGFR<60 ml/min/1.73 m2. A low eGFR was associated with an increased risk of in-hospital mortality [eGFR 60-89 ml/min/1.73 m2, odds ratio (OR) 1.36 (95% confidence interval (CI) 1.21-1.53); eGFR 45-59, 2.35 (1.97-2.82); eGFR<45, 4.18 (3.7-4.72); P for trend < 0.0001], non-routine discharge [eGFR 60-89, 1.11 (1.03-1.2); eGFR 45-59, 1.16 (1-1.35); eGFR<45, 1.37 (1.23-1.53); P for trend < 0.0001], hemorrhagic stroke severity [eGFR 60-89, 1 (0.95-1.05); eGFR 45-59, 1.39 (1.26-1.53); eGFR<45, 1.81 (1.67-1.96); P for trend < 0.0001], in-hospital complications of pneumonia [eGFR 60-89, 1.1 (1.05-1.14); eGFR 45-59, 1.3 (1.2-1.4); eGFR<45, 1.66 (1.57-1.76); P for trend < 0.0001] and hydrocephalus [eGFR 60-89, 0.99 (0.87-1.12); eGFR 45-59, 1.37 (1.1-1.7); eGFR<45, 1.54 (1.32-1.8); P for trend = 0.0139] after adjusting for confounding factors. With the decline in eGFR, the risk of hematoma evacuation increased in patients with an eGFR 45 to 59 ml/min/1.73 m2 (OR 1.48; 95% CI 1.37-1.61). No significant association between differences in eGFR at baseline and in-hospital complication of recurrent intracerebral hemorrhage was observed.

CONCLUSIONS

Low eGFR at baseline was associated with an increased risk of in-hospital mortality, non-routine discharge, hemorrhagic stroke severity and in-hospital complications such as pneumonia, hydrocephalus and hematoma evacuation in acute ICH patients.

Interactions Between Kidney Function and Cerebrovascular Disease: Vessel Pathology That Fires Together Wires Together

The kidney and the brain, as high-flow end organs relying on autoregulatory mechanisms, have unique anatomic and physiological hemodynamic properties. Similarly, the two organs share a common pattern of microvascular dysfunction as a result of aging and exposure to vascular risk factors (e.g., hypertension, diabetes and smoking) and therefore progress in parallel into a systemic condition known as small vessel disease (SVD). Many epidemiological studies have shown that even mild renal dysfunction is robustly associated with acute and chronic forms of cerebrovascular disease. Beyond ischemic SVD, kidney impairment increases the risk of acute cerebrovascular events related to different underlying pathologies, notably large artery stroke and intracerebral hemorrhage. Other chronic cerebral manifestations of SVD are variably associated with kidney disease. Observational data have suggested the hypothesis that kidney function influences cerebrovascular disease independently and adjunctively to the effect of known vascular risk factors, which affect both renal and cerebral microvasculature. In addition to confirming this independent association, recent large-scale human genetic studies have contributed to disentangling potentially causal associations from shared genetic predisposition and resolving the uncertainty around the direction of causality between kidney and cerebrovascular disease. Accelerated atherosclerosis, impaired cerebral autoregulation, remodeling of the cerebral vasculature, chronic inflammation and endothelial dysfunction can be proposed to explain the additive mechanisms through which renal dysfunction leads to cerebral SVD and other cerebrovascular events. Genetic epidemiology also can help identify new pathological pathways which wire kidney dysfunction and cerebral vascular pathology together. The need for identifying additional pathological mechanisms underlying kidney and cerebrovascular disease is attested to by the limited effect of current therapeutic options in preventing cerebrovascular disease in patients with kidney impairment.

Blood urea nitrogen, blood urea nitrogen to creatinine ratio and incident stroke: The Dongfeng-Tongji cohort

BACKGROUND AND AIMS

It remains unclear whether extreme levels of blood urea nitrogen (BUN) and BUN to creatinine ratio (BUN/Cr) can increase future risk of stroke. We conducted this study to investigate the associations of BUN and BUN/Cr with incident stroke and its subtypes.

METHODS

A total of 26,835 and 26,379 participants with a mean follow-up of 7.9 years were included to investigate the associations of BUN and BUN/Cr with incident stroke, respectively. Cox proportional hazard models were used to evaluate hazard ratios (HRs) and 95% confidence intervals (CIs) for incident stroke and its subtypes.

RESULTS

Compared with participants in the third quintile of BUN, the adjusted HRs (95% CIs) for participants in the lowest quintile were 1.21 (1.04-1.40), 1.41 (1.18-1.68) and 1.36 (0.97-1.91) for total, ischemic and hemorrhagic stroke, respectively; while for those in the highest quintile, the corresponding HRs (95% CIs) were 1.16 (1.01-1.32), 1.30 (1.11-1.53), and 1.24 (0.90-1.71). The associations remained robust when restricting the analyses to participants within clinically normal range of BUN. For BUN/Cr, compared with participants in the third quintile, participants in the lowest quintile had significant higher risks of stroke (HRs [95% CIs] were 1.19 [1.04-1.37], 1.26 [1.07-1.48], and 1.22 [0.90-1.67] for total, ischemic and hemorrhagic stroke).

CONCLUSIONS

Both high and low levels of BUN were associated with higher risks of total and ischemic stroke. Low level of BUN/Cr was associated with excess risks of total and ischemic stroke.

Epidemiology, thrombolytic management, and outcomes of acute stroke among patients with chronic kidney disease: a systematic review and meta-analysis

BACKGROUND

The relative frequency of ischemic versus hemorrhagic stroke among patients with chronic kidney disease (CKD) has not been clearly described. Moreover, no recent meta-analysis has investigated the outcomes of patients with CKD treated with thrombolysis for acute ischemic stroke. We conducted a systematic review and meta-analysis to estimate the proportion of stroke subtypes and the outcomes of thrombolysis in CKD.

METHODS

A PubMed, EMBASE and Cochrane literature research was conducted. The primary outcome was the proportion and incidence of ischemic versus hemorrhagic strokes among patients with CKD. In addition, we assessed the impact of CKD on disability, mortality, and bleeding among patients with acute ischemic stroke treated with thrombolysis. The pooled proportion and the risk ratio (RR) were estimated using a random-effects model.

RESULTS

Thirty-nine observational studies were included: 22 on the epidemiology of stroke types and 17 on the outcomes of thrombolysis in this population. In the main analysis (> 99,281 patients), ischemic stroke was more frequent than hemorrhagic among patients with CKD (78.3%, 95% confidence interval 73.3%-82.5%). However, among patients with kidney failure, the proportion of ischemic stroke decreased and was closer to that of hemorrhagic stroke: 59.8% (95% confidence interval 49.4%-69.4%). CKD was associated with worse clinical outcomes in patients with acute ischemic stroke compared with patients with preserved kidney function.

CONCLUSIONS

The relative frequency of hemorrhagic stroke seems to increase as kidney function declines. Among patients with acute ischemic stroke treated with thrombolysis, presence of CKD is associated with higher disability, mortality, and bleeding, compared with patients with preserved kidney function.

Antihypertensive treatment decrease stroke occurrence: a prospective cohort study

OBJECTIVE

Among the risk factors of stroke, hypertension was one of the most important and modifiable factors. The current study aimed to assess whether antihypertensive treatment to ideal levels of blood pressure can eliminate stroke risk in a prospective cohort study.

METHODS

The Kailuan study was a prospective longitudinal cohort study on stroke risk factors and events. We analyzed association of baseline antihypertensive treatment efficacy with the risk of stroke during 11.0-year follow-up, and further evaluated association of newly antihypertensive treatment efficacy at 4-year follow-up with subsequent stroke. Multivariate Cox proportion models were used to calculated hazard ratios and their 95% confidence intervals (CIs) for stroke.

RESULTS

A total of 97 772 participants (median age: 51.65 years) without previous stroke were included. At baseline, 55 518 participants had normotension, 2339 treated and controlled, 32 331 untreated hypertension and 7584 treated but uncontrolled. Compared with normotension, individuals with treated and controlled, untreated hypertension and treated but uncontrolled, had 83, 97 and 162% higher risk of developing total stroke after adjusting for potential stroke risk factors, respectively (hazard ratio 1.83 [95% CI 1.56-2.15], 1.97 [95% CI 1.85-2.11] and 2.62 [95% CI 2.40-2.86]; all P < 0.05). Whereas, normotension at baseline, who were newly normotension with antihypertensives at 4-year follow-up, exhibited no elevated total stroke risk (hazard ratio, 1.41 [95% CI 0.87-2.30]). Similar results existed for stroke subtypes (ischemic stroke and hemorrhagic stroke).

CONCLUSION

The data suggest that, antihypertensive treatment to normotensive individuals can reduce stroke risk in a short time.

Distinct eGFR trajectories are associated with risk of myocardial infarction in people with diabetes or prediabetes

BACKGROUND

The relationship between estimated glomerular filtration rate (eGFR) trajectories and myocardial infarction (MI) has so far been unclear in people with diabetes or prediabetes. We aimed to identify common eGFR trajectories in people with diabetes or prediabetes and to examine their association with MI risk.

METHODS

The data of this analysis were derived from the Kailuan study, which was a prospective community-based cohort study. The eGFR trajectories of 24 723 participants from the year 2006 to 2012 were generated by latent mixture modeling. Cox proportional hazards models were used to calculate hazard ratios (HR) and their 95% CI for the subsequent risk of MI of different eGFR trajectories.

RESULTS

We identified five distinct eGFR trajectories during 2006 to 2012 and named them according to their eGFR range and pattern over time: low-stable (9.4%), moderate-stable (31.4%), moderate-increasing (29.5%), high-decreasing (13.9%), and high-stable (15.8%). During a mean follow-up of 4.61 years, there were a total of 235 incident MI. Although the high-decreasing group had similar eGFR levels to the moderate-stable group during the last exposure period, the risk was much higher (adjusted HR, 3.57; 95% CI, 1.63-7.85 vs adjusted HR, 2.88; 95% CI, 1.36-6.08). Notably, the moderate-increasing group had reached the normal range, but still had a significantly increased risk (adjusted HR, 2.63; 95% CI, 1.24-5.55).

CONCLUSIONS

eGFR trajectories were associated with MI risk in people with diabetes or prediabetes. These observations suggest that long-term trajectories of eGFR may be important for risk prediction of MI and should be highlighted in primary prevention.

Relationship between high-sensitivity C reactive protein and the risk of gallstone disease: results from the Kailuan cohort study

OBJECTIVES

Gallstone disease (GSD) can be caused by various health and clinical factors such as obesity, dyslipidaemia and an unhealthy diet, all of which are associated with higher high-sensitivity C reactive protein (hs-CRP) concentrations. Whether hs-CRP represents an independent risk factor for GSD is still unclear. We prospectively investigated hs-CRP in relation to the occurrence of GSD based on the Kailuan study.

STUDY DESIGN

Prospective cohort study.

SETTING

The Kailuan cohort study was conducted in Tangshan City in northern China.

PARTICIPANTS

95 319 participants who were free from GSD were recruited in this study. Epidemiological data, anthropometric parameters and biochemical data of participants were collected.

PRIMARY AND SECONDARY OUTCOME MEASURES

Cox proportional hazards regression models were used to evaluate the association between hs-CRP concentrations and the risk of GSD after adjustments for potential confounders.

RESULTS

During the mean 7.58 years of follow-up among 95 319 participants, 4205 participants were identified as newly diagnosed with GSD or having undergone cholecystectomy for cholelithiasis. Compared with the hs-CRP<1 mg/L group, elevated hs-CRP concentrations were significantly associated with higher risk of GSD with the corresponding HR of 1.11 (95% CI 1.03 to 1.19), 1.12 (95% CI 1.04 to 1.22) in the 1≤hs-CRP≤3 mg/L and hs-CRP>3 mg/L group, respectively. The multivariate model which included hs-CRP not only had a better line of fitness but also had better predictive values to help identify new cases of GSD during follow-up.

CONCLUSION

Elevated hs-CRP concentration is an independent risk factor for new-onset GSD among the Chinese population.

TRIAL REGISTRATION NUMBER

ChiCTR-TNC-11001489.

Relationship Between Time-Dependent Proteinuria and Risk of Stroke in Population With Different Glucose Tolerance Status

Background

Proteinuria often changes and is known as a “time‐dependent exposure.” The effect of time‐dependent proteinuria on the risk of future stroke remains unclear. Proteinuria is often detected in patients with diabetes mellitus. The present study was designed to evaluate the association between time‐dependent proteinuria and the risk of stroke in a patient cohort with different glucose tolerance status.

Methods and Results

A total of 82 938 participants, who were free of myocardial infarction or stroke and underwent fasting blood glucose and urinary protein measurements at baseline in the Kailuan study, were enrolled. Proteinuria was determined using urine dipstick tests at baseline and subsequent follow‐ups. Time‐dependent proteinuria was defined as the status of urine protein updated through the follow‐up examinations, separately. Time‐dependent Cox regression models were used to analyze the relationship between time‐dependent proteinuria and the risk of stroke. During a median follow‐up of 8.37 years, 2538 participants developed stroke. After adjusting for confounding factors, the hazard ratio (95% CI) for stroke in time‐dependent proteinuria among all participants, and the normoglycemia, prediabetes, and diabetes mellitus populations were 1.68 (1.49–1.89), 1.73 (1.47–2.05), 2.15 (1.70–2.72), and 1.30 (1.03–1.65), respectively. There were interaction effects in patients with normoglycemia and prediabetes compared with those with diabetes mellitus. Findings were similar for ischemic and hemorrhagic strokes and were confirmed in sensitivity analyses.

Conclusions

Time‐dependent proteinuria is an independent risk factor of stroke, especially in the normoglycemia and prediabetes populations.

Effect of resting heart rate on the risk of all-cause death in Chinese patients with hypertension: analysis of the Kailuan follow-up study

OBJECTIVE

Previous studies have shown that an elevated heart rate is associated with a higher risk of cardiovascular events. This study aimed to prospectively examine the relationship between resting heart rate (RHR) and all-cause mortality in Chinese patients with hypertension.

DESIGN

An observational, prospective and population-based cohort study.

SETTING

The Kailuan cohort study was conducted in Tangshan City in northern China.

PARTICIPANTS

We enrolled 46 561 patients who did not receive beta-blocker treatment and were diagnosed with hypertension for the first time during an employee health examination in Kailuan Group in 2006 and 2008.

OUTCOME

The primary outcome of this study was all-cause mortality.

METHODS

The patients in this study were followed for 9.25±1.63 years. All patients were followed up face to face every 2 years. According to the distribution of RHR in the study population, RHR was categorised into five groups on the basis of quintiles: Q1: RHR ≤68 beats per minute (bpm); Q2: RHR >68 and ≤72 bpm; Q3: RHR >72 and ≤76 bpm; Q4: RHR >76 and ≤82 bpm; Q5: RHR >82 bpm. Cox proportional hazards model, which was adjusted for traditional risk factors, was used.

RESULTS

During follow-up, 4751 deaths occurred. After adjustment for potential confounders, restricted cubic spline regression showed that the risk of all-cause mortality increased with heart rate. In multivariate Cox regression analyses adjusted for age, sex and major covariates, the HR for all-cause mortality was 1.31 (95% CI 1.27 to 1.33) in the highest quintile group (Q5) compared with the lowest quintile group (Q1).

CONCLUSION

An increase in RHR is a long-term risk factor of all-cause mortality in Chinese patients with hypertension.

TRIAL REGISTRATION NUMBER

ChiCTR-TNC-11001489.

Change of Kidney Function Is Associated With All-Cause Mortality and Cardiovascular Diseases: Results From the Kailuan Study

Background

Current evaluation about the relationship of sequential change in estimated glomerular filtration rate (eGFR) and clinical outcomes are still inconsistent. We aimed to investigate the association between the change in kidney function over time and the risk of all‐cause mortality and cardiovascular disease.

Methods and Results

This prospective cohort including 37 691 participants aged ≥45 years used data from the Kailuan Health Registry. The relationship of the annual percentage and absolute change in eGFR and outcomes were analyzed with Cox proportional regression. The participants were stratified according to the quintiles distribution of the percentage annual change in eGFR (Q1–Q5). After adjusting for baseline covariates including initial eGFR, participants with annual eGFR decline were at significantly greater risk for all‐cause mortality (Q1: hazard ratio, 1.22 [95% confidence interval, 1.04–1.43]; Q2: 1.19 [1.01–1.40]) than noted for patients in Q3. Cardiovascular disease risk was also significantly higher in participants with annual eGFR decline (Q1 and Q2). No significantly increased risk of adverse outcomes was noted for patients with annual eGFR increased groups (Q4 and Q5). When considering the absolute eGFR annual change rate (no/mild/rapid decline), we obtained similar results in chronic kidney disease participants, whereas non–chronic kidney disease participants had less pronounced association of eGFR decline with cardiovascular disease, though not with mortality.

Conclusions

A decline in eGFR over time is associated with higher risk for all‐cause mortality and cardiovascular disease independent of initial eGFR and other known risk factors at baseline. Our data support the serial evaluation of change in kidney function as a better prognostic indicator than single eGFR assessments.

Role of Exosomes in Central Nervous System Diseases

There are many types of intercellular communication, and extracellular vesicles are one of the important forms of this. They are released by a variety of cell types, are heterogeneous, and can roughly be divided into microvesicles and exosomes according to their occurrence and function. Of course, exosomes do not just play a role in cell-to-cell communication. In the nervous system, exosomes can participate in intercellular communication, maintain the myelin sheath, and eliminate waste. Similarly, exosomes in the brain can play a role in central nervous system diseases, such as stroke, Alzheimer's disease (AD), Parkinson's disease (PD), prion disease, and traumatic encephalopathy (CTE), with both positive and negative effects (such as the transfer of misfolded proteins). Exosomes contain a variety of key bioactive substances and can therefore be considered as a snapshot of the intracellular environment. Studies have shown that exosomes from the central nervous system can be found in cerebrospinal fluid and peripheral body fluids, and that their contents will change with disease occurrence. Because exosomes can penetrate the blood brain barrier (BBB) and are highly stable in peripheral circulation, they can protect disease-related molecules well and therefore, using exosomes as a biomarker of central nervous system diseases is an attractive prospect as they can be used to monitor disease development and enable early diagnosis and treatment optimization. In this review, we discuss the current state of knowledge of exosomes, and introduce their pathophysiological roles in different diseases of the central nervous system as well as their roles and applications as a viable pathological biomarker.

Clinical Features of Nephrotic Syndrome with Cerebral Hemorrhage

Background

Cerebral hemorrhage has been increasingly reported in patients with nephrotic syndrome (NS). However, the clinical features and pathogenesis of NS patients with cerebral hemorrhage remain unclear.

Material/Methods

From January 2007 to August 2017, continuous NS patients with cerebral hemorrhage at the First Affiliated Hospital of Guangxi Medical University were selected. The clinical manifestations, laboratory measurements, and neurological images of these patients were collected and analyzed.

Results

Acute cerebral hemorrhage was recorded in 15 of 10 461 NS patients. The average age of these 15 patients (9 males and 6 females) was 50.87±23.27 years old. Among these 15 patients, conventional vascular risk factors were identified in 8 patients, hypoalbuminemia and proteinuria were recorded in all 15 patients, coagulopathy was observed in 9 patients, increased D-dimer level was recorded in 13 patients, hyperlipidemia was recorded in 11 patients, and impaired renal function was recorded in 9 patients. The hemorrhage developed in the lobe (n=9), basal ganglia (n=3), cerebellum (n=2), and cerebral hemisphere (n=1). Eight patients were in a coma on the day the cerebral hemorrhage occurred, while 12 patients had a poor prognosis after 30 days of hemorrhage onset.

Conclusions

Poor prognosis was recorded in NS patients with cerebral hemorrhage. Although conventional vascular risk factors have only been identified in 8 patients, biochemical abnormalities (hypoalbuminemia, proteinuria, elevated D-dimer, and hyperlipidemia) were recorded in the majority of these 15 patients. Furthermore, most of the hemorrhages developed in the lobes. Coagulopathy might be the potential pathogenesis of cerebral hemorrhage in NS patients.

Two-year changes in proteinuria and risk for myocardial infarction in patients with hypertension: a prospective cohort study

OBJECTIVE

To assess whether changes in proteinuria are associated with the incidence of myocardial infarction (MI) in patients with hypertension.

METHODS

The Kailuan study was a prospective longitudinal cohort study on cardiovascular risk factors and events. Hazard ratios with 95% confidence intervals (CIs) were calculated using Cox regression models.

RESULTS

A total of 24 926 hypertensive patients (mean age: 55.2 ± 10.9 years) without previous MI were included. After a mean follow-up of 6.8 years, 382 (1.5%) individuals developed MI. Participants with proteinuria at baseline had a 60% higher risk for developing MI as compared with participants without proteinuria at baseline (hazard ratio: 1.60, 95% CI: 1.12-2.29) after adjusting for dyslipidemia, diabetes mellitus and other cardiovascular risk factors. Compared with participants without proteinuria, individuals with incident proteinuria or persistent proteinuria during the follow-up had 54 and 141% higher risks for developing MI, respectively (hazard ratio: 1.54, 95% CI: 1.14-2.09 and hazard ratio: 2.41, 95% CI: 1.59-3.66; all P < 0.05).

CONCLUSION

Proteinuria is associated with an increased incidence of MI, but the association is likely to be underestimated if baseline measurements of proteinuria are used. Measures of changes in proteinuria, particular persistent proteinuria, are more likely to reflect the lifetime risk for MI.

Proteinuria and risk of stroke in patients with hypertension: The Kailuan cohort study

Proteinuria is associated with stroke, but the effects of changes in proteinuria on stroke risk are not well understood in the hypertensive population. This study examined whether proteinuria changes across 2-year assessments were associated with incident stroke in individuals with hypertension. We used visit data from 24 300 participants with hypertension of the Kailuan study who were stroke free at baseline. Based on the baseline and 2-year dipstick screening results, participants were classified as having no, remittent, incident, or persistent proteinuria. The relationship between proteinuria and stroke was analyzed using Cox proportional-hazards models after adjusting for potential variables. During a median of 6.89-year follow-up, we identified 1197 people with stroke. Compared to those with no proteinuria, stroke risk was significantly increased in participants with incident (hazard ratio [HR] 1.41, 95% CI, 1.05-1.77) and persistent proteinuria (HR 1.49, 95% CI, 1.25-1.89) after adjustment for other factors, which was consistent in ischemic stroke and intracerebral hemorrhage. No interaction was found between changes of proteinuria and diabetes mellitus in the hypertensive population. Changes in proteinuria exposure, particularly persistent proteinuria, play a role in reflecting the risk of stroke in patients with hypertension.

Estimated Glomerular Filtration Rate, Proteinuria, and Risk of Cardiovascular Diseases and All-cause Mortality in Diabetic Population: a Community-based Cohort Study

Data about associations between estimated glomerular filtration rate (eGFR) and proteinuria with cardiovascular diseases (CVDs) and all-cause mortality among diabetic population is less described. We aimed to describe these associations in Chinese diabetic population, and investigate the difference between sexes. The study was based on 8,301 diabetic participants in the Kailuan study, who was free of CVDs at baseline. We used Cox proportional hazard models to examine the associations of eGFR and proteinuria with CVDs and all-cause mortality. A stratified analysis by gender was performed. During a median follow-up of 8.05 years, 917 deaths and 813 incident CVDs occurred. Adjusted for all potential confounders, eGFR was associated with all-cause mortality, but not associated with incidence of CVDs. Compared to those with eGFR ≥ 90 ml/min/1.73 m², Participants with eGFR <45 ml/min/1.73 m² had 1.50 fold higher risk of all-cause mortality. Adjusted for all potential confounders, proteinuria was associated with risk of both CVDs and all-cause mortality. Additionally, the risk of all-cause mortality by proteinuria was greater in women than that in men. Both lower eGFR and proteinuria are independent risk factors for all-cause mortality in the Chinese diabetic population. Proteinuria conferred excessive risk for CVDs, and especially in women.

Association of Persistent, Incident, and Remittent Proteinuria With Stroke Risk in Patients With Diabetes Mellitus or Prediabetes Mellitus

BACKGROUND

Proteinuria often changes dynamically, showing either regression or progression. The impact of changes in proteinuria on future stroke risk remains largely unknown. We hypothesized that changes in proteinuria would be associated with stroke risk in patients with diabetes mellitus and prediabetes mellitus.

METHODS AND RESULTS

The study population included 17 380 participants with diabetes mellitus or prediabetes mellitus enrolled in a prospective Chinese cohort. From the baseline and 2-year dipstick screening results, participants were classified as having no proteinuria or remittent, incident, or persistent proteinuria. Reduction in proteinuria was calculated as the baseline minus 2-year proteinuria. Stroke outcomes were assessed in subsequent follow-ups. Data were analyzed using Cox proportional-hazards models. During a median follow-up of 6.9 years, we identified 751 patients with stroke. Stroke risk was increased for participants with persistent (hazard ratio [HR], 1.64; 95% confidence interval [CI], 1.18-2.30), incident (HR, 1.52; 95% CI, 1.22-1.89), and remittent (HR, 1.42; 95% CI, 1.01-2.02) proteinuria compared with those with no proteinuria. Persistent proteinuria was associated with a higher risk of stroke for participants with prediabetes mellitus (HR, 2.58; 95% CI, 1.58-4.22) compared with those with diabetes mellitus (HR, 1.35; 95% CI, 0.86-2.12 [P for interaction=0.0083]). Proteinuria reduction contributed to a decrease in stroke incidence (HR, 0.88; 95% CI, 0.81-0.95). The results were confirmed by sensitivity analyses.

CONCLUSIONS

Persistent, incident, and remittent proteinuria are independent indicators of stroke risk in both diabetic and prediabetic populations.

Changes in Proteinuria on the Risk of All-Cause Mortality in People with Diabetes or Prediabetes: A Prospective Cohort Study

BACKGROUND

Proteinuria has been related to all-cause mortality, showing regression or progression. However, few studies have focused on the relationship between proteinuria changes and all-cause mortality. The main purpose of this paper is to examine the associations between proteinuria changes and all-cause mortality in people with diabetes or prediabetes.

METHODS

Dipstick proteinuria at baseline and a 2-year follow-up were determined in the participants attending the Kailuan prospective cohort study. Participants were then divided into three categories: elevated proteinuria, stable proteinuria, and reduced proteinuria. Four Cox proportional hazard models were built to access the relations of proteinuria changes to all-cause mortality, adjusting for other confounding covariates.

RESULTS

A total of 17,878 participants were finally included in this study. There were 1193 deaths after a median follow-up of 6.69 years. After adjusting for major covariates and proteinuria at baseline, mortality risk was significantly associated with elevated proteinuria (hazard ratio (HR): 1.54, 95% confidence interval (CI): 1.33-1.79) and reduced proteinuria (HR: 0.70, 95% CI: 0.55-0.89), compared to those with stable proteinuria.

CONCLUSION

Proteinuria changes were independently associated with mortality risk in either diabetic or prediabetic population.

Changes in proteinuria and the risk of myocardial infarction in people with diabetes or pre-diabetes: a prospective cohort study

Background

The relationship between changes in proteinuria and myocardial infarction (MI) remains unclear in people with diabetes or pre-diabetes. We aimed to evaluate the predictive value and independent role of changes in proteinuria over a 2-year period in the incidence of MI in people with diabetes or pre-diabetes.

Methods

Based on the baseline and 2-year dipstick screening results from the Kailuan prospective cohort study, participants were divided into four categories: no proteinuria, remittent proteinuria, incident proteinuria, and persistent proteinuria. Four multivariable Cox proportional hazard models were built to adjust for the effects of different confounding covariates.

Results

Among the 17,625 participants in this study, there were a total of 238 incidents of MI during a median follow-up of 6.69 years. After adjusting for demography factors and laboratory indices, the association between persistent proteinuria and MI incidence was maintained (hazard ratio [HR] 2.50, 95% confidence interval [CI] 1.48–4.22). Every decrease of proteinuria from 2006 to 2008 was observed to be responsible for a 21% decline of MI incidence (HR 0.79, 95% CI 0.68–0.90). The interaction between changes in proteinuria and diabetes was confirmed with no effect on MI (P = 0.3371).

Conclusions

Persistent proteinuria is an independent risk factor for MI incidence in the pre-diabetic and diabetic population. These findings may help clinicians to interpret proteinuria changes in the outpatient setting and provide possible preventive approaches for people with pre-diabetes or diabetes.

Electronic supplementary material

The online version of this article (doi:10.1186/s12933-017-0586-7) contains supplementary material, which is available to authorized users.

Two-Year Changes in Proteinuria and the Risk of Stroke in the Chinese Population: A Prospective Cohort Study

Background

Whether changes in proteinuria are associated with incident stroke in the general population is unclear. This study aimed to investigate the association between changes in proteinuria and incident stroke and its subtypes.

Methods and Results

The current study included 60 940 Chinese participants (mean age, 50.69 years) who were free of stroke at the time of surveys (2006–2007 and 2008–2009). Participants were divided into 4 categories according to 2‐year changes in proteinuria: no proteinuria, remittent proteinuria, incident proteinuria, and persistent proteinuria. Cox proportional hazards models were used to calculate hazard ratios and their 95% CIs for stroke. After a median follow‐up period of 6.92 years, 1769 individuals developed stroke. After adjustment for confounding factors, incident proteinuria and persistent proteinuria were associated with increased risk of stroke (hazard ratio, 1.46 [95% CI, 1.26–1.68] and hazard ratio, 1.71 [95% CI, 1.42–2.06], respectively) compared with no proteinuria, which were higher than proteinuria detected at one single point (hazard ratio, 1.25; 95% CI, 1.09–1.43). The effect size for risk of stroke subtypes including ischemic stroke and hemorrhagic stroke was similar.

Conclusions

Changes in proteinuria exposure, particularly persistent proteinuria, are more likely to reflect the risk of stroke, compared with proteinuria collected at a single time point in the general population.

Cumulative Resting Heart Rate Exposure and Risk of All-Cause Mortality: Results from the Kailuan Cohort Study

The relationship between cumulative exposure to resting heart rate (cumRHR) and mortality remain unclear in the general population. In the Kailuan cohort study, resting heart rate (RHR) was repeatedly measured at baseline and at years 2 and 4 by electrocardiogram among 47,311 adults aged 48.70 ± 11.68. The cumRHR was defined as the summed average RHR between two consecutive examinations multiplied by the time interval between with two examinations [(beats/min) * year]. A higher RHR was defined as ≥80 beats/min, and the number of visits with a higher RHR was counted. During a median of 4.06 years of follow-up, a total of 1,025 participants died. After adjusting for major traditional cardiovascular risk factors and baseline RHR, the hazard ratio for the highest versus lowest quartile of cumRHR was 1.39 (95% CI: 1.07–1.81) for all-cause mortality. Each 1-SD increment in cumRHR was associated with a 37% (HR: 1.37, 95% CI: 1.23–1.52) increased risk of death and displayed a J-shaped relationship. Compared with no exposure, adults who had a higher RHR at all 3 study visits were associated with a 1.86-fold higher risk (95% CI: 1.33–2.61) of mortality. In summary, cumulative exposure to higher RHR is independently associated with an increased risk of mortality.

Proteinuria Is an Independent Risk Factor for First Incident Stroke in Adults Under Treatment for Hypertension in China

Background

Conflicting evidence exists regarding whether reduced estimated glomerular filtration rate (eGFR) and proteinuria are independent risk factors for stroke and its subtypes in hypertensive patients. This study investigated the association of these renal measures with first incident stroke in adults under treatment for hypertension in China.

Methods and Results

The study included 19 599 adults aged 45 to 75 years who participated in the China Stroke Primary Prevention Trial. Baseline eGFR was calculated using the Chronic Kidney Disease Epidemiology Collaboration creatinine equation. Proteinuria was assessed by qualitative dipstick urinalysis and in a subset by the quantitative albumin–creatinine ratio method. Cox regression analysis was used to examine the effects of eGFR and proteinuria on the risk of first incident stroke. During a median of 4.5 years of follow‐up, a total of 585 first strokes (472 ischemic strokes) were identified. Compared to participants without proteinuria, participants with proteinuria (trace or more by dipstick) had a 35% increased risk of first stroke: the adjusted hazard ratio (HR) (95% CI) was 1.35 (1.09–1.66, P=0.005). The results were robust in subgroup analyses. In a subset with data on proteinuria measured by quantitative albumin–creatinine ratio, a similar association was found. In both independent and combined analyses with proteinuria, eGFR was not significantly associated with stroke.

Conclusions

In adults under treatment for hypertension in China, baseline proteinuria measured by dipstick or quantitative albumin–creatinine ratio, but not reduced eGFR, was found to be an independent risk factor for first incident stroke and ischemic stroke.

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.