Kidney Cancer And Stroke: Is There A Link?

Stroke is a leading cause of death and long-term disability, with debilitating effects. Chronic kidney disease (CKD) is an independent risk factor for stroke, including both hemorrhagic and ischemic subtypes. CKD patients have a 30-fold higher risk of stroke morbidity and almost 90% of case mortality rates. CKD and end-stage renal disease (ESRD) are renal diseases that exemplify the potential risk for stroke. CKD has been associated with increased stroke risk, with patients on dialysis being four to ten times more likely to have a stroke than the general population. CKD patients with comorbidities such as hypertension and diabetes are at a particularly high risk of stroke.

CKD causes a myriad of changes in the body's normal physiology, including inflammation, atherosclerosis, vascular calcification, the effect of uremic toxins, cerebral blood flow dysautoregulation, dialysis techniques, vascular access, prothrombotic tendency, and anticoagulation. CKD and stroke share a common bidirectional interplay of cerebro-renal physiological events, highlighting a dual relationship for cause.

In CKD patients, impaired kidney function can lead to altered cerebral hemodynamics and cerebral oxygen saturation. CKD influences the development, progression, and restoration of ischemic brain damage. CKD increases the risk of intracerebral hemorrhage and cerebral microbleeds. CKD also increases the risk of large vessel stroke via its effects on carotid artery stenosis, plaque size, and carotid intima-media thickness. CKD is associated with a greater neurological deficit following ischemic stroke, a poor functional outcome, and greater mortality.

Stroke risk is higher in CKD patients on dialysis

Stroke is a leading cause of morbidity and mortality worldwide. Renal failure is a potent risk factor for stroke, and the risk of stroke is 5–30 times higher in patients with chronic kidney disease (CKD), especially on dialysis. CKD is an independent risk factor for both ischemic and hemorrhagic stroke.

Risk Factors

The risk factors for stroke in CKD patients include old age, hypertension, diabetes, previous cerebrovascular disease, and atrial fibrillation. The period of dialysis initiation constitutes the highest risk period for developing a new stroke. Non-modifiable risk factors such as older age, diabetes, male gender, non-Caucasian/Asian ethnicity, and a positive family history are also prevalent in CKD patients.

CKD and Dialysis

The risk of stroke is higher in CKD patients on dialysis compared to those who are not on dialysis. The initiation of dialysis itself is associated with a heightened risk of stroke. Patients with ESRD on dialysis have an 8–10 times greater incidence of stroke compared to the general population. The risk of hemorrhagic stroke is higher than the risk of ischemic stroke in hemodialysis (HD) patients when compared to peritoneal dialysis (PD) patients.

Management and Outcome

The outcome of stroke in CKD patients is generally poor, with higher mortality and diminished functional outcomes. Thrombolytic therapy for stroke in CKD has shown an increased risk of symptomatic intracranial hemorrhage or serious systemic hemorrhage. Control of hypertension and the judicious use of antiplatelet agents form the mainstay of stroke prevention in CKD patients.

CKD patients with comorbidities like hypertension and diabetes are at a high risk of stroke

Chronic kidney disease (CKD) is a risk factor for stroke, with CKD patients having a 5-30 times higher risk of stroke than the general population. CKD patients with comorbidities such as hypertension and diabetes are at an even higher risk of stroke. CKD patients with these comorbidities are a high-risk group that requires clinical prioritization and further research.

CKD and stroke share several risk factors, including hypertension, diabetes, and age. CKD is often under-recognized as a comorbidity in stroke patients, partly because patients with kidney disease have often been excluded from clinical trials of cerebrovascular interventions. CKD is also associated with treatment delays and suboptimal acute stroke care.

CKD patients with comorbid hypertension and diabetes have a higher risk of stroke due to the interplay of vascular co-morbidities and renal impairment. The initiation of dialysis is also associated with a heightened risk of stroke. CKD patients with these comorbidities are more likely to experience stroke symptoms during or within 30 minutes of a dialysis session, which can lead to misdiagnosis and delayed presentation.

The presence of proteinuria in CKD patients further increases the risk of stroke. Patients with CKD and proteinuria have a 70% greater risk of stroke than those without it.

CKD patients with comorbid hypertension and diabetes are at a particularly high risk of stroke and require clinical prioritization and further research.

CKD is often detected for the first time during stroke evaluation

Chronic kidney disease (CKD) is associated with a higher risk of stroke. In a study conducted on CKD patients admitted to a tertiary care referral centre, CKD was detected for the first time during stroke evaluation in 55.5% of the patients. The study was conducted on a total of 1369 CKD patients treated as inpatients from December 2004 to December 2006, out of which 27 patients (1.97%) were found to have had a stroke. The male:female ratio was 19:8, and the patients' ages ranged from 32 to 80 years (mean age: 59.14 years). The types of CKD observed were diabetic nephropathy (37%), hypertensive nephropathy (18.5%), chronic glomerulonephritis (11%), cystic kidney disease (3.7%), and other types (29%) of the patients. Renal failure was mild in 25.95%, moderate in 37.03%, and severe in 37.03% of the patients.

The stroke subtypes observed included infarction in 48%, haemorrhage in 40.7%, and both infarction and haemorrhage in 11.11% of the patients. The brain infarcts were found to arise due to large artery arteriosclerosis in 62.5% of the patients. Lacunar type infarcts were noted in 37.5% of patients. The vascular territory of brain infarction includes the carotid system in 56.25% and the vertibrobasilar system in 43.75% of the patients. Stroke in the form of cerebral haemorrhage was detected in 40.74% of the patients. The distribution of the sites of haemorrhagic stroke were the thalamus in 38.46%, basal ganglion in 38.46%, subcortical in 15.38%, and cerebellum in 7.69% of the patients. The risk factors for stroke were hypertension in 88.88% (uncontrolled hypertension 48.14%), anemia in 81.48%, diabetes in 48.14%, smoking in 33.33%, and hyperlipidaemia in 14.81% of the patients.

CKD patients have a higher risk of cerebral infarction and cerebral haemorrhage

• CKD is associated with a high risk of stroke, with patients on dialysis being four to ten times more likely to suffer a stroke than the general population.
• CKD is also a risk factor for both ischemic and hemorrhagic strokes.
• CKD patients have a higher risk of cerebral infarction and cerebral haemorrhage due to a number of factors, including hypertension, diabetes, and atrial fibrillation.
• CKD patients are also more likely to suffer from cerebral small vessel disease, which can lead to stroke.
• CKD is also associated with a higher risk of intracerebral haemorrhage, with CKD patients being more likely to have larger lobar hematomas and poor outcomes.
• CKD patients are also at risk of acute kidney injury, which can lead to increased mortality.
• CKD patients are also more likely to suffer from posterior reversible encephalopathy syndrome, which can lead to hyperperfusion and protein and fluid extravasation in the brain.

CKD patients have a higher risk of intracerebral haemorrhage and cerebral microbleeds

In a retrospective cohort including more than 500,000 participants, it was identified a stepwise association between eGFR and ICH, where the risk of haemorrhage decreased by 9% (95% CI 8–11%) for each 10 mL/min/1.73 m2 increase in eGFR, including after adjustment for medical comorbidities, albuminuria, antiplatelet therapy, and use of anticoagulants. Among patients with a recent ICH or ischemic stroke, an eGFR <60 mL/min/1.73 m2 was independently associated with the presence and number of cerebral microbleeds, particularly in patients with recent African ancestry. In patients on dialysis, ICH is associated with the highest mortality risk of all stroke subtypes. Uremic platelet dysfunction and use of heparin and other anticoagulants during the dialysis procedure may further increase the risk of intracerebral haemorrhage.

Frequently asked questions