Type 1 diabetes during pregnancy doubles the risk of autism in offspring

ORLANDO – The risk of autism spectrum disorder (ASD) is increased in children of mothers with new data on type 1 diabetes, suggesting that the severity of maternal diabetes and the timing of exposure may be important in l & # 39; Association.

Specifically, with type 1 diabetes during pregnancy, it was found that the risk of ASD in offspring increased, with a risk ratio of 2.33 (P = 0.005), compared to uncomplicated pregnancies with diabetes.

"What surprised us so much about our data was the level of risk of autism for children born to mothers with type 1 diabetes," says Anny Xiang, Ph.D., of Kaiser Permanente, Pasadena, California, who presented the study here. The American Diabetes Association (ADA) 2018 scientific sessions.

The results of the observational study were simultaneously published as a letter of JAMA.

The results also confirm and add to the existing knowledge of an association between ASD risk and gestational diabetes or type 2 diabetes during pregnancy (with the greatest risk if diagnosed at 26 weeks), such as Xiang and his colleagues (JAMA. 2015; 313: 1425-1434).

The moderator of the session, Peter Damm, MD, DMSc, professor of obstetrics at Rigshospitalet, Copenhagen, Denmark, said that he considered that it was a solid study, albeit with some limitations, such as the following: acknowledged the presenter.

"The discovery that type 1 diabetes during pregnancy has a higher risk rate for autism than type 2 diabetes, and even more so than gestational diabetes, reflects the degree of maternal and maternal hyperglycemia. seems reasonable, "he said.

"Similarly, the finding that women diagnosed with early gestational diabetes [≤ 26 weeks’ gestation] as opposed to the end have a higher risk, showing us a dose-response relationship with regard to the different types of diabetes and the risk of autism. "

Nevertheless, he pointed out that although diabetes during pregnancy seems to increase the risk of autism in offspring, this risk is very low to begin with.

"For the individual woman, there is a very small risk that her child will have this. I would never raise this subject with a patient unless my patient asks me to."

First study on the association between type 1 diabetes in mother and autism

"Our general interest is to examine the potential impact of hyperglycemia during pregnancy on neural behavioral disorders," explained Xiang. "Here in this study, we analyzed our data for any relationship between type 1 diabetes and autism because this has not been done before."

The new retrospective cohort analysis included singleton children born between 28-44 weeks over a 17-year period until 2012 in Kaiser Permanente hospitals in Southern California. The children were followed up in electronic records for a median follow-up time of 6.9 years for a clinical diagnosis of ASD, including autistic disorders, Asperger's syndrome, and non-specified Pervasive Developmental Disorder. elsewhere.

Type 1 diabetes has been identified with the help of an algorithm developed for electronic health records data and confirmed by the prescription of insulin during pregnancy.

The results were adjusted for possible confounding factors, including year of birth, mother's age at birth, parity, education, race / ethnicity self-reported, median family income, and history of comorbidity.

Of the 419,425 eligible children, 621 were exposed to type 1 maternal diabetes, 9,453 to type 2 maternal diabetes, 11,922 to gestational diabetes diagnosed at 26 weeks of gestation, and 24,505 to gestational diabetes diagnosed after 26 weeks of gestation.

Overall, 5827 children were diagnosed with ASD.

Adjusted risk of TSA in offspring associated with in utero exposure to pre-existing maternal diabetes during indexed pregnancy

* Year of birth, maternal age at birth, parity, educational attainment, self-reported race / ethnicity, median household income, history of comorbidity, smoking during pregnancy and BMI before pregnancy.

All mothers with type 1 and type 2 diabetes, but only 29% of those with gestational diabetes, received antidiabetic drugs during pregnancy.

The potential risk associated with antidiabetic drug exposure was assessed in the gestational diabetes group, taking into account potential confounding factors and gestational age at the time of diagnosis of gestational diabetes. The risks were not significantly different between those with versus no exposure to diabetes medications during pregnancy in the gestational diabetes group (adjusted HR, 1.18; P = 0.10).

Xiang pointed out that confusion due to paternal risk factors and other intrauterine and postnatal exposures should be evaluated to provide a more complete understanding. In addition, the potential role of maternal blood glucose, other characteristics of type 1 diabetes, premature birth and neonatal hypoglycemia remain to be explored.

In conclusion, Xiang and colleagues say, "These findings add new insights into type 1 diabetes and extend previous findings for pre-existing type 2 diabetes and gestational diabetes. However, "gestational diabetes diagnosed after 26 weeks of gestation was not associated with undue risk compared to the absence of diabetes".

Clinical implications of the results

Xiang explained that pregnancy is a screening opportunity for women with an existing underlying defect.

"Pregnant women are often young and would never think about being tested for diabetes, but they may already have underlying glucose intolerance that can lead to gestational diabetes and possibly diabetes," she said. she declared.

Reflecting on the clinical implications of the findings, she observed, "Regardless of whether the woman has type 2, type 1 diabetes, or gestational diabetes, women should really be treated with drugs during pregnancy."

"In gestational diabetes, most receive lifestyle information, but drugs start only if glucose levels reach a certain threshold. For now, we do not have continuous glucose monitoring data to know if the glycemic control is sub-optimal. during pregnancy."

"It's important for the patient and the clinician to monitor blood glucose control as closely as possible and make sure it's normal from conception."

Echoing this, Damm pointed out that glucose monitoring during pregnancy would be stricter, but warned that "the discovery of an increased risk of autism with diabetes is not only associated to glycemic control but also to other factors. "

"As a clinician, I do not think we will change the practice because we are already trying to control metabolism as well as possible in women with diabetes during pregnancy or gestational diabetes," he concluded. .

The authors have not reported any relevant financial relationship.

American Scientific Diabetes Association 2018 Scientific Sessions. June 22, 2018; Orlando Florida. Summary 117-OR.

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