Increased Risk of High Refractive Error in Children of Mothers with Diabetic Complications

Article: New study reveals that children of mothers with diabetes during pregnancy have an increased risk of eye problems
Source: Diabetologia, European Association for the Study of Diabetes (EASD), via ScienceDaily
Published: August 17, 2021

A nationwide population-based cohort study comprised of more than 2.4 million individuals born in Denmark between 1977 and 2016, with follow-up spanning up to 25 years, found that mothers who have diabetes before or during their pregnancy were at an increased risk of having children who go on to develop high refractive error (RE). Including conditions such as myopia, hyperopia, and astigmatism, refractive errors collectively result in defocus of the retinal image and if the degree of refractive error is high enough, can contribute to visual impairment. Based on earlier studies showing links between refractive error and congenital eye defects, the researchers suspected that maternal hyperglycemia during pregnancy could lead to elevated fetal blood glucose levels, which in turn can damage the retina and optic nerve and lead to changes in the shape of the eyes that ultimately cause RE. The results indicate that among the study population, 2.3% were exposed to maternal diabetes, with 0.9% and 0.3% being type 1 and type 2 pre-gestational diabetes respectively, and 1.1% involving gestational diabetes. Exposure to maternal diabetes was associated with a 39% greater risk of high RE compared to unexposed offspring, with elevated risk observed in all three types of refractive error. There was also a difference between type 1 and type 2 diabetes; compared to unexposed offspring, rates of high RE were 32% higher in offspring of mothers with type 1 diabetes and 68% higher in offspring of mothers with type 2 diabetes. Most notably, offspring of mothers with complications arising from diabetes were twice as likely (200%) to have high RE, compared to 18% in unexposed offspring. All this being said, the actual numbers of incidence were low. For example, the authors report, "During up to 25 years of follow-up, 553 offspring of mothers with diabetes and 19,695 offspring of mothers without diabetes were diagnosed with high RE." Although 553 individuals is a tiny number in a sample size of 2,470,580, the authors stress the importance of early screening and prevention, stating, "[A]ny tiny improvement in this low-risk preventable factor will contribute to a huge reduction in absolute numbers of these eye conditions."

My rating of this study: ⭐⭐⭐⭐

Du J, Li J, Liu X, et al. "Association of maternal diabetes during pregnancy with high refractive error in offspring: a nationwide population-based cohort study." Diabetologia.  17 August 2021. https://doi.org/10.1007/s00125-021-05526-z