Association between body composition and retinal vascular caliber in children and adolescents

To elucidate the relationship between body composition and retinal vascular caliber (RVC) in children and adolescents.

Participants aged 7 to 19 years were recruited from the Guangzhou Twin Eye Study cohort. Retinal vascular caliber was measured cross-sectionally from retinal images using a computer-aided program. The data were expressed as the central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE). Triceps skinfold thickness (TSFT) was measured using a skinfold caliper. Body composition was obtained through bioelectrical impedance analysis, providing fat mass (FM), fat mass index (FMI), fat-free mass (FFM), fat-free mass index (FFMI), body water mass (BWM), body water percentage (BWP), basal metabolic rate (BMR), and trunk fat percentage (TFP).

A total of 731 participants were included. Among the younger children (7-11 years), there was no significant association between body composition and RVC (all P > 0.05). However, for the older children (12-19 years), increasing FM, FMI, TFP, TSFT, and BMI were associated with CRAE negatively (β = -0.20, -0.68, -0.18, -0.17, and -0.48, respectively, all P < 0.05) and with CRVE positively (β = 0.47, 1.26, 0.34, 0.37, and 0.78, respectively, all P < 0.05), after adjusting for age, sex, axial length, mean arterial blood pressure, and the fellow vascular diameter. In contrast, increase in BWP was associated with larger CRAE (β = 0.33, P = 0.001) and smaller CRVE (β = -0.64, P < 0.001). Similar associations also were observed in the analyses when the body composition parameters were divided into quartiles (all P < 0.05).

In adolescents, greater body fat deposition is related to narrower retinal arterioles and wider retinal venules, and higher body water proportion is associated with retinal arterioles widening and retinal venules narrowing. Even during childhood, body composition might have an association with systemic microvasculature.