LAUSR

BACKGROUND We previously found that blood pressure (BP) is elevated, and associated with poorer neurocognition, in youth with bipolar disorder (BD). While higher BP is associated with smaller brain structure in adults, studies have not examined this topic in BD or youth. METHODS Participants were 154 youth, ages 13-20 (n=81 BD, n=73 HC). Structural magnetic resonance imaging and diastolic (DBP), and systolic (SBP) pressure were obtained. Region of interest (ROI; anterior cingulate cortex [ACC], insular cortex, hippocampus) and vertex-wise analyses controlling for age, sex, body-mass-index, and intracranial volume investigated BP-neurostructural associations; a group-by-BP interaction was also assessed. RESULTS In ROI analyses, higher DBP in the overall sample was associated with smaller insular cortex area (β=-0.18 p=0.007) and was associated with smaller ACC area to a significantly greater extent in HC vs BD (β=-0.14 p=0.015). In vertex-wise analyses, higher DBP and SBP were associated with smaller area and volume in the insular cortex, frontal, parietal, and temporal regions in the overall sample. Additionally, higher SBP was associated with greater thickness in temporal and parietal regions. Finally, higher SBP was associated with smaller area and volume in frontal, parietal, and temporal regions to a significantly greater extent in BD vs HC. LIMITATIONS Cross-sectional design, single assessment of BP. CONCLUSION BP is associated with brain structure in youth, with variability related to structural phenotype (volume vs. thickness) and psychiatric diagnosis (BD vs. HC). Future studies evaluating temporality of these findings, and the association of BP changes on brain structure, in youth are warranted.