Relationships between cerebral blood flow and cognition in young adults born very preterm and at term.

The mechanisms underpinning persistent cognitive challenges in young adults born very preterm (VP; < 32 weeks' gestation) are unclear, but may include altered cerebral blood flow (CBF). We explored whether CBF differed between adults born VP and at term, and the associations between CBF and cognitive outcomes. Seventy-two participants born VP and 16 term-born controls born in Victoria, Australia, completed Arterial Spin Labelling-MRI and a neuropsychological assessment at 20 years of age. Using a voxel-wise general linear model, we analyzed CBF differences between VP and term-born individuals, and the relationships between CBF and cognitive outcomes. Adults born VP displayed lower CBF in several subcortical regions compared with their term-born peers. For both birth groups combined, CBF was positively associated with verbal delayed memory in frontal and temporal cortical regions, and negatively associated with executive functioning in frontal, temporal, occipital cortical regions and the cerebellum. Compared with the VP group, term-born adults exhibited stronger negative relationships between CBF and IQ, receptive language, and aspects of executive functioning. Few CBF-cognition relationships were observed in the VP group and when present, were positive. Overall, adults born VP exhibited lower CBF in subcortical regions with cortical CBF-cognition relationships in opposite directions across VP and term groups. These disparities may reflect cerebral dysmaturation in the VP group.