Denmark: Offspring of mothers with type 1 diabetes (O-mT1D) achieved lower test scores compared to offspring of parents from the background population (O-BP) but similar tests scores with offspring of fathers with type 1 diabetes (O-fT1D), a recent study has found.
The study, published in the journal Plos Medicine, however, reduces the previous concerns with regards to adverse effects of in utero hyperglycemia on offspring cognitive function. In simpler words, regardless of which biological parent has type 1 diabetes, cognitive development in children could be affected. The research for the first time has shown that having a parent with a chronic disease like type 1 diabetes may be associated with lower school performance rather than maternal high blood sugar during fetal development.

Results on possible adverse effects on the cognitive function of O-mT1D have been conflicting. Previous studies have included offspring of parents from the background population but not offspring of fathers with type 1 diabetes as the unexposed reference group. Against the above background, Anne Lærke Spangmose, Copenhagen University Hospital, Rigshospitalet, Copenhagen, Denmark, and colleagues aimed to compare test scores in O-mT1D with test scores in O-fT1D and O-BP. The team hypothesized that O-mT1D would achieve lower test scores compared with O-fT1D and O-BP due to intrauterine exposure of hyperglycemia.
For this purpose, the researchers conducted a population-based retrospective cohort study from 2010 to 2016. They obtained nationally standardized school test scores (range, 1 to 100) for public school grades 2, 3, 4, 6, and 8 in O-mT1D and compared with those in O-fT1D and O-BP. A total of 622,073 children were included out of which 2,144 were O-mT1D, and 3,474 were O-fT1D.
The outcomes including the covariates offspring with type 1 diabetes, parity, number of siblings, offspring sex, smoking during pregnancy, parental age, and socioeconomic factors were compared using Multiple linear regression models.
Based on the study, the researchers reported the following findings:
Mean test scores were 54.2 (standard deviation, SD 24.8) in O-mT1D, 54.4 (SD 24.8) in O-fT1D, and 56.4 (SD 24.7) in O-BP.
In adjusted analyses, the mean differences in test scores were −1.59 between O-mT1D and O-BP and −0.78 between O-fT1D and O-BP.
No significant difference in the adjusted mean test scores was found between O-mT1D and O-fT1D.
The study's limitation was no access to measures of glycemic control during pregnancy.
"The researchers found that both O-mT1D and O-fT1D had lower test scores than O-BP," wrote the authors. "However, there were no differences in test scores for O-mT1D and O-fT1D. O-mT1D had a slightly increased risk of missing a test score compared with O-fT1D and a lower overall math test score."
For women with type 1 diabetes, these results are reassuring, as one of their main concerns is whether dysregulation of diabetes during their pregnancy may cause impaired cognitive development in their coming children, they noted.
Reference:
Spangmose AL, Skipper N, Knorr S, Wullum Gundersen T, Beck Jensen R, Damm P, et al. (2022) School performance in Danish children exposed to maternal type 1 diabetes in utero: A nationwide retrospective cohort study. PLoS Med 19(4): e1003977. https://doi.org/10.1371/journal.pmed.1003977