Imaging brain vascular function in Cystic Fibrosis: an MRI study of cerebral blood flow and brain oxygenation

Background: Cystic fibrosis (CF) is a progressive inherited disorder that primarily affects the lungs. With recent breakthroughs in effective treatments for CF that increase life-expectancy, a higher prevalence of age-related comorbidities has been reported including cardiovascular disease, stroke and cognitive decline. Despite the known relationship between cardiovascular health and cerebrovascular function, very little is known about brain blood flow and oxygen metabolism in people with CF (PwCF). Methods: In 14 PwCF and 56 healthy age / sex matched controls, we used pseudo-continuous arterial spin labelling (pCASL) to quantify cerebral perfusion in grey-matter and T₂-Relaxation-Under-Spin-Tagging (TRUST) to estimate global oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen consumption (CMRO₂). Results: Compared to healthy controls, PwCF showed elevated CMRO₂ (p = 0.015). There were no significant between-group differences in grey-matter CBF (p = 0.342), or whole brain OEF (p = 0.091). However, regional analysis showed certain areas with higher CBF in PwCF (p < .05, FDR). Conclusions: Our results show increased CMRO₂ and regional CBF in PwCF, which could be explained by potential differences in PaO₂/PaCO₂ and/or endothelial cell function. Our findings highlight the need for further investment in brain research in PwCF to reduce the risk of early cerebrovascular breakdown that leads to premature cognitive decline.