Arterial stiffness relates to executive dysfunction in later life

Arterial stiffness mediates the association between age and processing speed at low levels of microvascular function in humans across the adult lifespan

The function of micro- and macrovessels within the peripheral vasculature has been identified as a target for the investigation of potential cardiovascular-based promoters of cognitive decline. However, little remains known regarding the interaction of the micro- and macrovasculature as it relates to cognitive function, especially in cognitively healthy individuals. Therefore, our purpose was to unravel peripheral factors that contribute to the association between age and processing speed. Ninety-nine individuals (51 men, 48 women) across the adult life span (19-81 yr) were used for analysis. Arterial stiffness was quantified as carotid-femoral pulse-wave velocity (cfPWV) and near-infrared spectroscopy assessed maximal tissue oxygenation (Sto2max) following a period of ischemia. Processing speed was evaluated with Trail Making Test (TMT) Parts A and B. Measures of central (cPP) and peripheral pulse pressure (pPP) were also collected. Moderated mediation analyses were conducted to determine contributions to the age and processing speed relation, and first-order partial correlations were used to assess associations while controlling for the linear effects of age. A P ≤ 0.05 was considered statistically significant. At low levels of Sto2max, there was a significant positive (b = 1.92; P = 0.005) effect of cfPWV on time to completion on TMT part A. In addition, cPP (P = 0.028) and pPP (P = 0.027) remained significantly related to part A when controlling for age. These results suggested that the peripheral microvasculature may be a valuable target for delaying cognitive decline, especially in currently cognitively healthy individuals. Furthermore, we reinforced current evidence that pulse pressure is a key endpoint for trials aimed at preventing or delaying the onset of cognitive decline.NEW & NOTEWORTHY Arterial stiffness partially mediates the association between age and processing speed in the presence of low microvascular function, as demarcated by maximum tissue oxygenation following ischemia. Central and peripheral pulse pressure remained associated with processing speed even after controlling for age. Our findings were derived from a sample that was determined to be cognitively healthy, which highlights the potential for these outcomes to be considered during trials aimed at the prevention of cognitive decline.

The influence of modifiable cardiovascular risk factors on cognition, functioning, and inflammatory markers in first-episode psychosis: Results from a 2-year follow-up study

To explore the influence of cardiovascular risk factors (CVRFs) on cognitive symptoms, functional impairment, and systemic inflammatory markers in first-episode psychosis (FEP) patients at baseline and 2-year follow-up. Method: In a sample of 70 FEP patients and 85 age- and sex-matched healthy controls, we assessed nine modifiable CVRFs. All participants were classified into two subgroups according to their CVRF profile: lower (0-1 CVRFs) or higher (≥2 CVRFs). The following outcomes were measured at baseline and 2-year follow-up: cognition; functional outcomes; and white blood cell (WBC) subtype. Adjusted general linear models were conducted to study the effect of diagnosis and CVRF profile on cognition, functioning, WBC, and longitudinal changes in these variables. At baseline, FEP patients with a higher CVRF profile showed a significantly slower performance on the TMT-A test for psychomotor speed and higher lymphocyte levels than patients with a lower CVRF profile. No longitudinal changes were observed in primary outcomes at 2-year follow-up. Among FEP patients with a higher CVRF profile, slower psychomotor speed performance did not correlate with increased lymphocyte levels. Our findings suggest that the cognitive effects of CVRFs manifest early in the course of psychosis, thus highlighting the importance of targeting both CVRFs and cognitive deficits in FEP.

Sex Differences in the Relationship Between Arterial Stiffness and Cognitive Function in Older Adults

OBJECTIVE

To examine potential sex differences in the relationship between arterial stiffness and global cognitive function and executive functions.

METHODS

Baseline data from 80 older adults were included from two randomized controlled trials (NCT02669394 and NCT02737878). Arterial stiffness was measured by carotid-femoral pulse wave velocity (cf-PWV). Cognitive function assessment included global cognition (Mini-Mental State Examination [MMSE]) and executive functions (set shifting [Trail Making Test Part B minus A], inhibition [Stroop Test], and working memory [Verbal Digit Span Backwards Test]). Separate statistical models were constructed to assess the effect of cf-PWV on each cognitive outcome for females and males. Each statistical model controlled for Framingham cardiovascular disease risk score and education.

RESULTS

Higher cf-PWV was associated with impaired MMSE performance in males (β = -0.48; p = 0.018), but not females (p ≥ 0.389). For executive processes, higher cf-PWV was associated with impaired Trail Making Test Part B minus A (β = 0.56; p = 0.005) and Stroop Test (β = 0.59; p = 0.004) in males, but not in females (ps ≥ 0.108). cf-PWV was not significantly associated with Verbal Digit Span Forward minus Backward Test in males or females (ps ≥ 0.108).

CONCLUSIONS

Arterial stiffness is more strongly associated with cognitive impairment in males than females. These results further elucidate the interplay between vascular health and cognitive function by providing support for sex-specific mechanisms.

Association of Aortic Stiffness and Cognitive Decline: A Systematic Review and Meta-Analysis

Background: Increased aortic stiffness has been found to be associated with cognitive function decline, but the evidence is still under debate. It is of great significance to elucidate the evidence in this debate to help make primary prevention decisions to slow cognitive decline in our routine clinical practice.

Methods: Electronic databases of PubMed, EMBASE, and Cochrane Library were systematically searched to identify peer-reviewed articles published in English from January 1, 1986, to March 16, 2020, that reported the association between aortic stiffness and cognitive function. Studies that reported the association between aortic pulse wave velocity (PWV) and cognitive function, cognitive impairment, and dementia were included in the analysis.

Results: Thirty-nine studies were included in the qualitative analysis, and 29 studies were included in the quantitative analysis. The aortic PWV was inversely associated with memory and processing speed in the cross-sectional analysis. In the longitudinal analysis, the high category of aortic PWV was 44% increased risk of cognitive impairment (OR 1.44; 95% CI 1.24–1.85) compared with low PWV, and the risk of cognitive impairment increased 3.9% (OR 1.039; 95% CI 1.005–1.073) per 1 m/s increase in aortic PWV. Besides, meta-regression analysis showed that age significantly increased the association between high aortic PWV and cognitive impairment risk.

Conclusion: Aortic stiffness measured by aortic PWV was inversely associated with memory and processing speed and could be an independent predictor for cognitive impairment, especially for older individuals.

Carotid Artery Stiffness is Associated With Cognitive Performance in Former Smokers With and Without Chronic Obstructive Pulmonary Disease

Background Heavy smokers perform worse on neuropsychological assessment than age-matched peers. However, traditional pulmonary measures of airflow limitation and hypoxemia explain only a modest amount of variance in cognition. The current objective was to determine whether carotid artery stiffness is associated with cognition in former smokers beyond the effects of amount of smoking and pulmonary function. Methods and Results Eighty-four former smokers including individuals across a spectrum of airflow limitation severity were included: 30 without chronic obstructive pulmonary disease (Global Initiative for Chronic Obstructive Lung Disease [GOLD] 0 with normal spirometry and lung computed tomography), 31 with mild-moderate chronic obstructive pulmonary disease (GOLD 1-2), and 23 with severe-very severe chronic obstructive pulmonary disease (GOLD 3-4). Participants completed questionnaires, spirometry, carotid ultrasonography, and neuropsychological testing. Multiple linear regression was used to determine whether carotid artery stiffness is associated with neuropsychological performance in 4 cognitive domains after adjusting for age, sex, pack-years of smoking, estimated premorbid intellectual functioning, and airflow limitation. Higher carotid artery β-stiffness index was associated with reduced executive functioning-processing speed in the fully adjusted model (β=-0.49, SE=0.14; P=0.001). Lower premorbid intellectual function, male sex, and presence of airflow limitation (GOLD 1 or 2 and GOLD 3 or 4) were also associated with worse executive functioning-processing speed. β-Stiffness index was not significantly associated with performance in other cognitive domains. Conclusions Carotid artery stiffness is associated with worse performance on executive functioning-processing speed in former smokers beyond the effects of aging, amount of past smoking, severity of airflow limitation, and hypoxemia. Future research should examine whether carotid stiffness can be used to identify former smokers at risk for subsequent cognitive impairment.