Common carotid flow velocity is associated with cognition in older adults

Differential association of flow velocities in the carotid artery with plaques, intima media thickness and cardiac function

Background and aims

We aimed to determine the association of carotid intima media thickness (CIMT), carotid plaques, and heart function with peak systolic velocity (PSV) of the common (CCA) and internal carotid artery (ICA) in a cross-sectional study.

Methods

In the population-based Hamburg-City-Health-Study participants between 45 and 74 years were recruited. Cardio-vascular risk factors were assessed by history, blood samples, and clinical examination. CIMT, plaques, and PSV were determined by carotid ultrasound. Serum N-terminal brain natriuretic peptide (NT-proBNP) was determined as a biomarker for cardiac dysfunction, and left ventricular ejection fraction (LVEF) was quantified by echocardiography. Participants with carotid stenosis were excluded. Data were analyzed by multivariate linear regression.

Results

We included 8567 participants, median age was 62 years, 51.8% were women. Median CIMT was 0.75 mm, NT-proBNP 80 pg/ml, LVEF 58.5%, and 30.4% had carotid plaques. For women PSV decreased in decades from 89 to 73 cm/s in CCAs and 78 to 66 cm/s in ICAs, and for men from 91 to 76 cm/s in CCAs and from 70 to 66 cm/s in ICAs. Corrected for age, sex, red blood cell count, and blood pressure, in CCAs lower PSV was associated with carotid plaques (p < 0.001; β = -0.03), lower CIMT (p = 0.005; β = 0.007), higher levels of log-transformed NT-proBNP (p < 0.001; β = -0.01), and lower LVEF (p < 0.001; β = 0.01). In ICAs, lower PSV was independently associated with lower CIMT (p < 0.001; β = 0.02) and lower EF (p = 0.001; β = 0.007).

Conclusions

Markers of cardiac dysfunction and plaques are associated with lower and CIMT with higher flow velocities in the carotid arteries.

Clinical Trial Registration

http://www.clinicaltrials.gov, NCT03934957.

The association between carotid blood flow and resting-state brain activity in patients with cerebrovascular diseases

Cerebral hypoperfusion impairs brain activity and leads to cognitive impairment. Left and right common carotid arteries (CCA) are the major source of cerebral blood supply. It remains unclear whether blood flow in both CCA contributes equally to brain activity. Here, CCA blood flow was evaluated using ultrasonography in 23 patients with cerebrovascular diseases. Resting-state brain activity and cognitive status were also assessed using magnetoencephalography and a cognitive subscale of the Functional Independence Measure, respectively, to explore the relationships between blood flow, functional brain activity, and cognitive status. Our findings indicated that there was an association between blood flow and resting-state brain activity, and between resting-state brain activity and cognitive status. However, blood flow was not significantly associated with cognitive status directly. Furthermore, blood velocity in the right CCA correlated with resting-state brain activity, but not with the resistance index. In contrast, the resistance index in the left CCA correlated with resting-state brain activity, but not with blood velocity. Our findings suggest that hypoperfusion is important in the right CCA, whereas cerebral microcirculation is important in the left CCA for brain activity. Hence, this asymmetry should be considered when designing appropriate therapeutic strategies.

Effects of Carotid Artery Stent and Carotid Endarterectomy on Cognitive Function in Patients with Carotid Stenosis

BACKGROUND

Carotid artery stenosis is closely related to cognitive dysfunction, in which decreased cerebral perfusion is one of the important factors. Both carotid artery stent implantation and carotid endarterectomy can relieve stenosis and increase cerebral perfusion. In this study, we aimed to compare the effects of carotid artery stent implantation and endarterectomy on cognitive function.

METHODS

A total of 98 patients with carotid artery stenosis hospitalized in our hospital from July 2015 to January 2017 were included. Among them, 50 cases underwent carotid artery stent implantation treatment as stent implantation group (CAS group), and 48 cases underwent carotid artery endarterectomy treatment as carotid endarterectomy group (CEA group). Using the Mini-Mental State Examination Scale (MMSE Scale) and the Montreal Cognitive Assessment Scale (MoCA Scale), the cognitive function scores of the two groups of patients before and after 3 and 6 months of operation were measured, and the patients were also measured before and after surgery, after the serum NSE, hs-CRP content.

RESULTS

The serum NSE, hs-CRP content, MMSE score, and MoCA score of the two groups before treatment were not statistically significant (P > 0.05). The MMSE score and MoCA score of the two groups of patients before treatment were lower than the normal value, suggesting carotid artery stenosis combined with different degrees of cognitive dysfunction. Carotid artery stenosis is different, and patients' cognitive function is also different. The MMSE score and MoCA score of the two groups at 3 and 6 months after operation were higher than before treatment, and there was a statistically significant difference between 6 and 3 months after operation (P < 0.05), but at each time There was no statistically significant difference between the two groups (P > 0.05). The NSE content of the two groups of patients after operation decreased compared with that before treatment, and the decrease in 6 months after operation was more obvious than that in March (P < 0.05). However, the difference between the two groups at each time point was not statistically significant (P > 0.05). The content of hs-CRP in the two groups of patients was higher than that before the operation, and the CAS group was significantly higher than the CEA group; the difference was statistically significant (P < 0.05).

CONCLUSION

Carotid artery stent and carotid endarterectomy are effective in improving the cognitive function of patients with carotid stenosis, but there is no significant difference between the two.

Common carotid flow velocity is associated with cognitive function after carotid endarterectomy

The relationship between ultrasonographic flow parameters and cognitive function has not been well studied. This study aimed to clarify associations between carotid flow velocity (FV) and cognitive function in patients with a history of carotid endarterectomy (CEA). Ninety-four patients who previously underwent CEA participated in this study. The Neurobehavioral Cognitive Status Examination (Cognistat) and Frontal Assessment Battery (FAB) were adopted to assess cognitive functions at a mean of 6.5 ± 3.2 years after CEA. End-diastolic flow velocity (EDV) of the left and right common carotid artery (CCA) was significantly associated with total Cognistat score (p < 0.001) and total FAB score (p < 0.05). Pulsatility index (PI) of the left CCA was significantly associated with total Cognistat score and total FAB score (p < 0.01). A cut-off right CCA EDV of 14.5 cm/s offered the most reliable predictor of the bottom 25th percentile of total Cognistat score (sensitivity 83.3%, specificity 61.0%, area under the curve (AUC) 0.731, p = 0.0060), while a cut-off left CCA PI of 1.83 was the most reliable predictor of the bottom 25th percentile of total FAB score (sensitivity 73.3%, specificity 60.0%, AUC 0.679, p = 0.0179). Left and right CCA EDV correlated with sub-components of comprehension, construction, judgment, programming (p < 0.01), and conceptualization (p < 0.05). Right CCA EDV correlated with similarity (p < 0.01), repetition, naming, and memory (p < 0.05). Left CCA PI correlated with attention, conceptualization (p < 0.01), repetition, construction, similarity, and mental flexibility (p < 0.05), while right CCA PI correlated with construction (p < 0.05). CCA FV may offer useful markers of cognitive functions in patients with a history of CEA.

Carotid Flow Velocities and Blood Pressures Are Independently Associated With Cognitive Function

BACKGROUND

Few studies simultaneously addressed associations between carotid flow velocities, blood pressure (BP), and cognitive function.

MATERIALS AND METHODS

Subject without dementia (N = 1,684) underwent measurements of BP and biochemical markers. Mini-Mental State Examination (MMSE) and comprehensive neuropsychological tests were used to evaluate cognitive function. Peak systolic velocity (PSV) and end-diastolic velocity (EDV) were measured in common and internal carotid artery. Subjects with MMSE score of ≤24 (25th percentile) was defined as low MMSE. Multivariable linear and logistic regression were used to evaluate the relationship of cognitive function with carotid flow velocities and BP.

RESULTS

Carotid flow velocities (PSV: standardized β = 0.067, P = 0.0009; and EDV: standardized β = 0.067, P = 0.0021) and systolic blood pressure (standardized β = -0.061, P = 0.005) were positively and negatively associated with MMSE, respectively, in the model with adjustments for age, sex, educational attainment, nutritional status, and smoking. Similar trends were noted for the associations between flow velocities and different neuropsychological tests. By multivariable logistic regression, the group with the lowest quartile (<25th percentile) of flow velocities had increased probability of low MMSE (odds ratio: 1.538; 95% confidence intervals: 1.142 to 2.071, P = 0.0046 for PSV; and odds ratio: 1.699; 95% confidence intervals: 1.233 to 2.341; P = 0.0012 for EDV), compared to those with the highest quartile (≥75th) flow velocities.

CONCLUSION

Both low carotid flow velocity and high BP were independently and comparably associated with cognitive dysfunction.

Relationships Among Cognitive Function and Cerebral Blood Flow, Oxidative Stress, and Inflammation in Older Heart Failure Patients

BACKGROUND

The mechanisms for cognitive impairment in heart failure (HF) are unclear. We investigated the relative contributions of cerebral blood flow velocity (BFV), oxidative stress, and inflammation to HF-associated cognitive impairment.

METHODS AND RESULTS

Thirty-six HF patients (≥60 years) and 40 healthy controls (68 ± 7 vs 67 ± 5 years, P > .05; 69% vs 50% male, P > .05) completed the Cognitive Drug Research computerized assessment battery and Stroop tasks. Common carotid (CCA) and middle cerebral arterial BFV were obtained by transcranial Doppler. Blood samples were collected for oxidant (diacron-reactive oxygen metabolites; F2-isoprostanes), antioxidant (coenzyme Q10; CoQ10), and inflammatory markers (high-sensitivity C-reactive protein). Compared with controls, patients exhibited impaired attention (Cognitive Drug Research's Power of Attention domain, congruent Stroop) and executive function (incongruent Stroop). Multiple regression modeling showed that CCA-BFV and CoQ10 but not group predicted performance on attention and executive function. Additionally, in HF patients, CCA-BFV and CoQ10 (β = -0.34 vs β = -0.35) were significant predictors of attention, and CCA-BFV (β = -0.34) was a predictor of executive function.

CONCLUSIONS

Power of Attention and executive function is impaired in older HF patients, and reduced CCA-BFV and CoQ10 are associated with worse cognition. Interventions addressing these mechanisms may improve cognition in older HF patients.

Carotid artery stiffness and hemodynamic pulsatility during cognitive engagement in healthy adults: a pilot investigation

BACKGROUND

The matching of vascular supply to neuronal metabolic demand during cognitive engagement is known as neurovascular coupling (NVC). Arterial stiffness is a prominent determinant of pulsatility in the systemic circulation and may thus indirectly impact NVC. In this pilot investigation, we explored changes in carotid artery stiffness and cerebrovascular hemodynamic pulsatiltiy during cognitive engagement in healthy adults.

METHODS

Twenty-seven adults (age 39 ± 3 years, BMI 24 ± 1 kg/m(2)) underwent Doppler ultrasonography of the common carotid artery (CCA) combined with applanation tonometry to derive (i) CCA elastic modulus (Ep) and β-stiffness index; (ii) CCA flow pulsatility index (PI); (iii) CCA pulse pressure, (iv) CCA augmentation index (AIx). Cerebral PI was assessed using transcranial Doppler at the middle cerebral artery (MCA). All measures were made at rest and during an incongruent Stroop task.

RESULTS

CCA PI was reduced (1.75 ± 0.06 to 1.57 ± 0.06, P < 0.05) while MCA PI was unchanged (0.75 ± 0.02 to 0.75 ± 0.02, P > 0.05) during Stroop. Brachial pulse pressure increased during Stroop (43 ± 1 to 46 ± 1 mm Hg, P < 0.05) while CCA pulse pressure was unchanged (36 ± 1 to 35 ± 1 mm Hg, P > 0.05). Similarly, CCA Ep (54.5 ± 5.5 to 53.8 ± 4.9 kPa, P > 0.05) and β-stiffness index (4.4 ± 0.4 to 4.2 ± 0.3 aU, P > 0.05) were unchanged. CCA AIx increased (1 ± 4 to 13 ± 4%, P < 0.05).

CONCLUSION

Carotid pressure pulsatility is unaltered while carotid flow pulsatility is reduced during cognitive engagement. Carotid artery stiffness does not change suggesting that factors other than the dynamic elastic properties of the CCA buffer cerebrovascular hemodynamic pulsatility during cognitive engagement.