A German research study, led by investigators at the Department of Ophthalmology, University of Mainz, have demonstrated an association between low birth weight and low visual acuity in adulthood. The research findings, built on data collected by the Gutenberg Health Study, demonstrated that a low birth weight is associated with low visual acuity and with long-term refractive outcomes in adulthood. The research demonstrated that study participants with low birth weight are more likely than not to have a lower visual acuity measurement and a higher myopic refractive error in adulthood, compared to participants with either a normal or high birth weight.
The reported research represented a population based observational cohort study that included 15,010 participants between the ages of 35 and 74 years. Participants were split into three different categories based on their birth weight – low birth weight: below 2500 g; normal birth weight: from 2500g to 4000 g; and high birth weight: above 4000 g. The researchers looked at data on BCVA and objective refraction and used multi-variable linear regression models, using a range of adjustments (age, sex, socioeconomic status, glaucoma, age-related macular degeneration, corneal disease, cataract) to uncover associations between birth weight and the study’s main outcome measures of BCVA, spherical equivalent and astigmatism.
The results of the study reported on the associations between birth weight and vision outcomes among 8,369 participants, representing a little over half of the cohort that were able to self-report their birth weights. The mean age of all participants was 51.5±10.6 years with 53.5% female and 46.5% male representation. Overall, 458 participants reported a low birth weight <2500 g, 6,854 participants reported a birth weight between 2500 and 4000 g and 1,057 participants reported a birth weight >4000 g. Results from a multivariable analysis showed an association for low birth weight with spherical equivalent (B=−0.28 per dioptre, P=0.005) and best-corrected visual acuity (B=0.02 logarithm of the minimum angle of resolution, P=0.006), when compared with normal birth weight. For study participants with high birth weight, an association was observed with spherical equivalent (B=0.29 per dioptre, P<0.001), but none with visual acuity. The German research group published their findings in the British Journal of Ophthalmology and summarized their findings that the “results demonstrate that low [birth weight] has an impact on visual acuity and refractive error several decades later in adulthood. Individuals with low [birth weight] are more likely to have lower visual acuity and a higher myopic refractive error in adulthood. In addition, low [birth weight] participants revealed more frequently a myopic refractive error of <−3 dioptre and < 6 dioptre and wear glasses for distance vision. However, although there was a statistical association, the absolute amount of difference was relatively small. Our data suggest that the influence of low [birth weight] lasts until adulthood.”