Abstract
Purpose: :
Elevated blood pressure is associated with generalized retinal arteriolar narrowing in adults, but the vascular effects of blood pressure in children is unknown. We describe the relationship between blood pressure and retinal vascular caliber in children.
Methods: :
We assessed retinal photographs taken in a population–based cross–sectional study of 384 children aged 7–9 years participating in the School Cohort Study of Risk Factors for Myopia (SCORM). The calibers of all arterioles and venules transiting the zone between one–half and one disc diameter from the optic disc margin were measured using a computer–based program, and combined to provide the average retinal arteriolar and venular caliber in that eye. Blood pressure was taken using an automated sphygmomanometer in a standardized setting. Associations between these retinal vascular measurements and blood pressure were analyzed.
Results: :
Mean arteriolar and venular caliber measurements were normally distributed, as was blood pressure. Higher mean arterial blood pressure (MABP) was associated with narrower retinal arteriolar caliber (age–gender–adjusted, p=0.008) but not with venular caliber (p=0.81). For every 10mmHg increase in MABP, retinal arteriolar caliber decreased by 2.25µm (95% CI: 3.60 to 0.90; p=0.001), adjusted for age and gender. This association remained significant (2.61µm, 95% CI: 3.92 to 1.29; p<0.001) after additional adjustment for parental income, height, weight, axial length, birthweight and gestational age, and was similar for systolic and diastolic blood pressures. There was no significant change in retinal venular caliber with blood pressure.
Conclusions: :
Elevated blood pressure is associated with narrowed retinal arteriolar caliber in normotensive children. These data suggest that the vascular effects of high blood pressure may occur in early childhood. The long–term significance of these vascular changes with respect to ocular and systemic diseases requires further investigation.
Keywords: retina • blood supply • clinical (human) or epidemiologic studies: risk factor assessment