Association of birth parameters with OCT measured macular and retinal nerve fiber layer thickness

To examine whether birth parameters have associations with macular and retinal nerve fiber layer (RNFL) thickness measurements.

The Sydney Myopia Study examined secondary school children for ocular conditions, with all eligible year 7 students from 21 high schools invited to participate. Macular and RNFL measurements were acquired from optical coherence tomography (OCT) scans. Birth variables, including birth weight and gestational duration, were obtained from parental questionnaires and health records. Mixed linear models were used in analyses, after adjustment for age, sex, height, axial length, and ethnicity.

In children with complete gestational duration data, adequate quality scans of the RNFL and macula were obtained from 1756 and 1698 children, respectively. Children with low birth weight (<2500 g) had a thinner mean RNFL (98.2 μm vs. 103.5 μm; P < 0.0001) and a thicker mean foveal minimum (164.3 μm vs. 158.5 μm; P = 0.004) than did children of normal birth weight (2500-4000 g). With increasing birth weight, average RNFL thickness increased (mixed model coefficient, β = 2.97 μm/kg; P < 0.0001) and foveal minimum thickness decreased (β = -2.16 μm/kg; P = 0.008). Children born before 32 weeks' gestation had significantly thicker mean foveal minimum and central macular thickness (205.5 μm vs. 193.4 μm; P = 0.001) measurements than did children born after 37 weeks' gestation.

Low birth weight and prematurity are associated with thickening of the fovea, and decreased birth weight is associated with decreased RNFL thickness, as measured by OCT. These findings suggest that premature birth and low birth weight impair retinal development and may predispose these children to ocular problems later in life.