Associations of retinal microvascular caliber with large arterial function and structure: A population-based study of 11-12 year-olds and mid-life adults.

OBJECTIVE We examined associations between retinal microvascular and large arterial phenotypes to explore relationships between the micro- and macro-vasculature in childhood and mid-life. METHODS Participants were 1288 children (11-12 years, 50.9% female) and 1264 adults (mean age 44 years, 87.6% female) in a cross-sectional population-based study. Exposures were retinal arteriolar and venular caliber quantified from retinal images. Outcomes included arterial function (pulse wave velocity, PWV; carotid arterial elasticity) and structure (carotid intima-media thickness, CIMT). Multivariable regression models were performed adjusting for age, sex and family socioeconomic position. RESULTS In children, one standard deviation (SD) wider arteriolar caliber was associated with slower PWV (-0.09SD, 95%CI -0.16, -0.02) and higher elasticity (0.13SD, 95%CI 0.06, 0.20); per SD wider venular caliber was associated with faster PWV (0.06SD, 95%CI -0.01, 0.12) and lower elasticity (-0.08SD, 95%CI -0.14, -0.01). The size of adult associations was approximately double. Wider arteriolar caliber was associated with smaller CIMT (-0.09SD, 95%CI -0.16, -0.03) in adults but not children. Venular caliber and CIMT showed little evidence of association. CONCLUSIONS Narrower retinal arterioles and wider venules are associated with large arterial function as early as mid-childhood. Associations strengthen by mid-life and also extend to arterial structure, although effect sizes remain small.