A composite haemodynamic-vascular metric informs mild vascular cognitive impairment risks in a stroke-free healthy ageing population

This study aimed to investigate whether the combination of systemic cardiovascular and cerebral haemodynamic measures yields a robust metric that strongly associates with mild vascular cognitive impairment (VCI), independently of underlying cerebral small vessel diseases (CSVD) and intracranial atherosclerosis (ICAS) in stroke-free healthy ageing adults. In this cross-sectional study, stroke-free adults underwent neurocognitive testing, neurosonology, and brain MRI, and were classified as cognitively normal or mild-VCI using standardised criteria. Systemic pulse pressure, carotid pulsatility index (PI), and cerebrovascular reactivity (CVR) were measured. These parameters were integrated into a composite haemodynamic-vascular dysfunction risk (Com-HVDR) score. Haemodynamic-vascular measures were compared between cognitively normal and mild-VCI groups. Correlation analysis explored the direction and association between the haemodynamic-vascular parameters and the different cognitive domains. Multivariate logistic regression analysis evaluated the strength of the association between Com-HVDR and mild-VCI status, adjusting for covariates. Among 162 adults (mean age = 66.2 years), 24.7% met the criteria for mild-VCI. Compared with cognitively normal participants, those with mild-VCI exhibited significantly lower CVR, higher PI, and increased systemic pulse pressure. The Com-HVDR score was significantly elevated in the mild-VCI group (1.42 ± 0.06 vs. 1.23 ± 0.08, p < 0.001). Cohort-based stratification by Com-HVDR tertiles showed that 57.5% of mild-VCI cases clustered in the high-score category, 32.5% in the moderate-score category, and only 10% in the low-score category. Higher Com-HVDR scores correlated with a decrease in overall cognitive performance ( r =-0.27, 95%CI: -0.40, -0.12, p < 0.001) and specifically showed negative correlations with memory, abstract reasoning, executive functions, visuospatial function, naming and attention. In a multivariate logistic regression analysis similar to the individual haemodynamic-vascular parameters, Com-HVDR scores remained independently associated with mild-VCI after adjusting for age, CSVD, ICAS, years of education, and other vascular risk factors (unadjusted OR = 5.68, 95%CI: 1.78–18.18, p = 0.003; age-adjusted OR = 6.05, 95%CI: 1.85–19.80, p = 0.003; and fully-adjusted OR = 7.76, 95%CI: 2.07–28.39, p = 0.003). Composite haemodynamic-vascular metrics, derived from systemic cardiovascular and cerebrovascular haemodynamic measures, are strongly associated with mild-VCI in stroke-free adults, independently of underlying CSVD, ICAS, and vascular risk factors. Although longitudinal studies are needed, these cross-sectional findings suggest that multidimensional haemodynamic–vascular assessments may be useful for understanding variations in cognitive status in ageing populations.