Optic disc parameters and associations with early life exposures in over 3 000 12-year-old children: findings from the ALSPAC cohort

Abstract Objectives We aimed to investigate the distribution of cupped and small optic discs in children and to examine associations with maternal and environmental factors. Methods Retinal photographs were graded from over 3000 12-year-olds in the Avon Longitudinal Study of Parents and Children. Regression models examined associations between disc parameters and maternal and early-life exposures. Results Mean cup-to-disc area ratio (CDAR) for 3288 children was 0.21 (95%CI 0.20,0.21). Cupped discs (CDAR >0.3) were present in 11%. The odds of disc cupping were increased nearly three-fold in underweight children (adjusted odds ratio (aOR) 2.9 (1.1, 7.3) p=0.03) and 28-fold in severely premature (<28 weeks) children (paOR 28 95%CI 4.6,172, p<0.001) with nearly one in four children affected. Mean cup-to-fovea/disc diameter (CF/DD) for 3327 children was 2.48 (95%CI 2.47,2.50). Small discs (CF/DD >3) were present in 6% of which a third were bilateral. The odds of a small disc were increased in the offspring of mothers who smoked in pregnancy (aOR 1.7 (1.0,2.8) p=0.04) and more than doubled in children born with a small head circumference (aOR 2.5 (1.4,4.5) p<0.001). Conclusions Cupped and small optic discs are more frequent than usually supposed at age 12. The odds of disc cupping are increased by severe prematurity and pathologically low BMI. The odds of a small disc are increased by maternal smoking and small head circumference. Optimisation of risk factors in pregnancy and delivery and early childhood nutrition may play an important role in ophthalmic neurodevelopment and thus have a lifelong impact on ocular health.