Choroidal thickness in relation to birth parameters in 11-12 year-old children: The Copenhagen Child Cohort 2000 Eye Study

Purpose: To examine choroidal thickness in a population-based child cohort in relation to birth parameters. Methods: The Copenhagen Child Cohort 2000 Eye Study examined 1406 children aged 11 to 12 years using enhanced-depth-imaging spectral-domain optical coherence tomography (EDI-OCT), ocular biometry and measurement of height, weight, refraction, and self-reported pubertal development status. Birth parameters were obtained from the Danish Medical Birth Registry. Results: The subfoveal choroid in low birth weight children (<2500 g, n=51, mean 324±76 μm) was thinner than in normal birth weight children (2500-4500 g, n=1194, mean 361±78 μm), the difference being -37 (CI95 -60 to -15) µm, P=0.001 after adjusting for age, sex, height, Tanner stage by sex, axial length, anterior chamber depth and spherical equivalent refractive error. The subfoveal choroid in high birth weight children (>4500 g, n=48, mean 351±63 μm) was comparable to normal birth weight children, P=0.44. The subfoveal choroid was thinner in preterm children however the difference was not significant (-18 (-37 to 2) µm, P=0.08). Small-for-gestation children had thinner subfoveal choroid (-19 (-37 to -1) µm, P=0.04) compared with appropriate-for-gestation children. Longer birth length was associated with a thicker subfoveal choroid (2 (1 to 4) µm/cm, P=0.005). Macular choroidal thickness at 16 extrafoveal locations was measured in a subset of children and found to have the same associations with birth weight as the subfoveal choroidal thickness. Conclusion: In 11-12 years old children, thinner choroids were associated with lower birth weight, lower birth length and being small for the gestational age.