Retinal vessel diameter, obesity and metabolic risk factors in school children (JuvenTUM 3)

Background: The prevalence of childhood obesity is high and its association with future cardiovascular disease in adulthood is well established. The cross-sectional data presented analyze the prevalence of obesity and the association between metabolic risk factors, physical inactivity and retinal vessel diameter in young school children. Methods: The examination included 578 school children aged 11.1 ± 0.6. years from secondary schools in the District of Munich, Germany. Anthropometric measurements and blood sampling were conducted using standard protocols for children. Physical activity was evaluated by use of a questionnaire. Retinal microvascular diameters and the arteriolar to venular ratio (AVR) were assessed with a non-mydriatic vessel analyser (SVA-T) using a computer-based program. Results: In our population, 128 (22.2%) children were overweight (ow) or obese (ob). The mean retinal arteriolar and venular calibres were 208.0 ± 15.6 μm and 236.2 ± 16.2 μm, respectively, with a mean AVR of 0.88 ± 0.01. Girls had significantly wider arteriolar and venular diameters compared to boys (p< 0.001). ow and ob children had a lower AVR compared to normal weight (nw) children (mean(95% CI); nw: 0.89(0.88-0.89); ow: 0.87(0.86-0.88); ob: 0.85(0.83-0.87); p≤ 0.05). Wider venular diameters were independently associated with higher BMI and higher hsCRP. Blood pressure was associated with retinal vessel constriction. Higher physical inactivity and BMI were independently associated with a reduced AVR (p= 0.032 and p< 0.001, respectively). Conclusions: Cardiometabolic risk factors and physical inactivity are associated with retinal microvascular alterations in young children, comparable to associations in adults. Retinal vessel imaging seems to be a feasible assessment for the detection of microvascular impairments in children at risk of developing cardiovascular disease in adulthood.