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Updated: Jun 29, 2025
Assessment of Vascular Function in Patients With Chronic Kidney Disease
Published on: June 16, 2014
Cerebrovascular carbon dioxide reactivity is intact in chronic kidney disease
Justin D Sprick1, Jeann Sabino-Carvalho2,3, Elsa Mekonnen2,3
1Department of Kinesiology, Health Promotion and Recreation, University of North Texas, Denton, Texas, USA.
Insights
Chronic kidney disease (CKD) does not impair cerebrovascular carbon dioxide reactivity (CVR). However, CVR was found to be inversely related to estimated glomerular filtration rate (eGFR) in CKD patients, suggesting other stroke risk factors.
Area of Science:
- Nephrology
- Neurology
- Cardiovascular Science
Background:
- Chronic kidney disease (CKD) is linked to a higher risk of cerebrovascular diseases, such as stroke.
- Impaired cerebrovascular carbon dioxide reactivity (CVR) is a potential mechanism contributing to this increased risk.
- Understanding CVR in CKD patients is crucial for identifying stroke risk factors.
Purpose of the Study:
- To compare CVR between CKD patients (stages III-IV) and a control group matched for hypertension and diabetes.
- To investigate the relationship between CVR and estimated glomerular filtration rate (eGFR) in CKD patients.
Main Methods:
- CVR was measured using 5% CO2 inhalation and voluntary hyperventilation.
- Continuous monitoring of mean arterial pressure, end-tidal carbon dioxide (etCO2), and middle cerebral artery blood velocity (MCAv).
- CVR quantified as the linear relationship between etCO2 and MCAv.
Main Results:
- No significant difference in CVR was observed between CKD patients and controls.
- Hypercapnic CVR: CKD = 1.2 ± 0.9 cm/s/mmHg vs. CON = 1.3 ± 0.8 cm/s/mmHg.
- Hypocapnic CVR: CKD = 1.3 ± 0.9 cm/s/mmHg vs. CON = 1.5 ± 0.7 cm/s/mmHg.
- Integrated CVR: CKD = 1.5 ± 1.1 cm/s/mmHg vs. CON = 1.7 ± 0.8 cm/s/mmHg (p ≥ 0.48).
- A significant inverse relationship was found between CVR and eGFR in CKD patients (R² = 0.37, p = 0.02).
Conclusions:
- Cerebrovascular carbon dioxide reactivity (CVR) remains intact in patients with chronic kidney disease (CKD).
- CVR is inversely related to estimated glomerular filtration rate (eGFR) in CKD.
- These findings suggest that mechanisms other than CVR contribute to the elevated stroke risk in CKD.
Abstract:
Chronic kidney disease (CKD) is characterized by an elevated risk for cerebrovascular disease including stroke. One mechanism that may contribute to this heightened risk is an impairment in cerebrovascular carbon dioxide reactivity (CVR). We compared CVR between CKD patients stages III-IV and controls (CON) without CKD but matched for hypertension and diabetes status. CVR was measured via 5% CO2 inhalation followed by voluntary hyperventilation in 14 CKD and 11 CON participants while mean arterial pressure, end-tidal carbon dioxide, and middle cerebral artery blood velocity (MCAv) were measured continuously. CVR was quantified as the linear relationship between etCO2 and MCAv. We observed no difference in CVR between groups. Hypercapnic CVR: CKD = 1.2 ± 0.9 cm/s/mm Hg, CON = 1.3 ± 0.8 cm/s/mm Hg, hypocapnic CVR: CKD = 1.3 ± 0.9 cm/s/mm Hg, CON = 1.5 ± 0.7 cm/s/mm Hg, integrated CVR: CKD = 1.5 ± 1.1 cm/s/mm Hg, CON = 1.7 ± 0.8 cm/s/mm Hg, p ≥ 0.48. Unexpectedly, CVR was inversely related to estimated glomerular filtration rate in CKD (R2 = 0.37, p = 0.02). We report that CVR remains intact in CKD and is inversely related to eGFR. These findings suggest that other mechanisms beyond CVR contribute to the elevated stroke risk observed in CKD.
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