Association of birth weight with corneal aberrations in adulthood - Results from a population-based study

Abstract

Purpose: Low birth weight (BW) is associated with increased corneal aberrations in childhood and alterations of corneal geometry in adulthood. Increased corneal aberrations may be a factor contributing to decreased visual function in former low BW newborns in later life. Hence, the aim of this study was to analyze the long-term effect of low BW on corneal aberrations in adulthood.

Methods: In the German population-based Gutenberg Health Study (GHS) participants (age: 40-80 years) were examined with Scheimpflug imaging (Pentacam HR, Oculus Optikgeräte GmbH, Wetzlar, Germany). The relationship between self-reported BW and the different types of corneal aberrations was analyzed using linear regression analysis as uni- and multivariable analysis with adjustment for potential confounders. The main outcome measures were corneal aberrations defined as astigmatism (Z₂^-2; Z₂²), coma (Z₃^-1; Z₃¹), trefoil (Z₃^-3; Z₃³), spherical aberration (Z₄⁰) and root-mean square of higher order aberrations (HOA; 3rd up to 8th order; aperture size: 6 mm).

Results: Overall, 5,628 participants were included in this analysis (3,004 women, aged 56.0 +/- 10.3 years). In a multivariable analysis lower BW was associated with decreased horizontal trefoil (B = 0.004 [0.001; 0.006] µm/500 g; p=.008); higher spherical aberrations (B=-0.006 [-0.008;-0.003] µm/500 g; p<.001), higher RMS (B=-0.028 [-0.042;-0.014] µm/500 g; p<.001), increased HOA (B=-0.007 [-0.010;-0.003] µm/500 g; p<.001) and increased LOA (B=-0.027 [-0.041;-0.013] µm/500 g; p<.001). No association was observed between birth weight and the other types of corneal aberrations in multivariable model.

Conclusion: Our results indicate an association between BW and spherical aberration in adults aged 40 to 80 years. This indicates that low BW may have an association with an altered corneal shape development which may affect optical image quality and, hence, visual function.

Keywords: Anatomy; Birth weight; Cornea; Corneal aberrations; Epidemiology.

Fig. 1

Scatterplot of birth weight with a) spherical aberrations and b) higher-order aberrations in the Gutenberg Health Study (n = 5628). Participants with lower birth weights showed higher spherical aberration and increased higher-order aberrations.

Fig. 2

Associations of the different corneal aberration types with birth weight (continuous) in the Gutenberg Health Study (2012–2017). Linear regression analysis using generalized estimating equations to control for correlations between right and left eyes. Estimates are present per 500 g. B – Beta; CI – Confidence interval M1 Crude model without adjustment. M2 Model adjusted for age; sex; corneal power, axial length, white-to-white, pseudophakia, IOP. A p-value <0.001 was considered as strong association, p<.05 as likely association, p≥.05 as not statistically significant association.

Fig. 3

Associations of the different corneal aberration types with Birth Weight Groups (low birth weight n = 313; normal birth weight n = 4629; high birth weight n = 686) in the Gutenberg Health Study (2012–2017). B – Beta; CI – Confidence interval Linear regression analysis using generalized estimating equations to control for correlations between right and left eyes. M1 Crude model without adjustment. M2 Model adjusted for age; sex; corneal power, axial length, white-to-white, pseudophakia, IOP. A p-value <0.001 was considered as strong association, p<.05 as likely association, p≥.05 as not statistically significant association.