Department of Research & Evaluation News

After previously finding strong associations between a mother’s diabetes and her child’s risk of developing autism, Anny Xiang, PhD, a researcher with the Kaiser Permanente Southern California Department of Research & Evaluation, decided to expand her work and look at other neurological development disorders.

In a research article released today in Diabetes Care, she targeted attention deficit hyperactivity disorder, commonly known as ADHD. She discovered that the severity of a mother’s diabetes during pregnancy was associated with the risk of her child developing ADHD. (For example, type 1 diabetes, in which the body makes none of its own insulin, would be considered more severe than type 2, in which the body cannot process its own insulin well, or gestational diabetes, which is a condition that can occur during pregnancy.)

“We wanted to see if what we learned from our studies of autism could be found for ADHD, one of the most common developmental disorders, as well,” Dr. Xiang said. “We found that there were similar associations between maternal diabetes and ADHD and that the more severe forms of a mother’s diabetes are associated with a greater risk of her child developing ADHD.”

Diabetes increases risk of having child with ADHD

Pregnant women with type 1 diabetes had a 57% higher risk of having a child who would develop attention deficit hyperactivity disorder than mothers without diabetes. The study showed that the risk of ADHD in offspring was greatest for mothers with type 1 diabetes, followed by mothers with type 2 diabetes who needed medications to control their blood sugar during pregnancy, then by mothers with gestational diabetes who needed medications to control their blood sugars.

Mothers with gestational diabetes who did not require anti-diabetic medication had a risk similar to those who did not have any type of diabetes.

The study is part of a growing body of evidence that maternal diabetes is associated with a child’s neurological developmental disorders. Dr. Xiang, PhD, who led this study, also recently published about the association between maternal diabetes and child’s autism risk.

More than 300,000 children were included in study

The study cohort included 333,000 children of diverse ethnicities born between 1995 and 2012 at Kaiser Permanente Southern California hospitals. The children were followed through electronic medical records beginning at age 4 years.

Among the study’s findings:

• Compared to no diabetes exposure, type 1 diabetes was associated with the greatest risk (57%), followed by type 2 diabetes requiring anti-diabetic medication during pregnancy (43%), and gestational diabetes requiring anti-diabetic medication during pregnancy (26%).
• Gestational diabetes not requiring anti-diabetic medication treatment during pregnancy had no increased risk.
• The timing of a gestational diabetes diagnoses during pregnancy (early and late in gestation) was not associated with child’s ADHD risk.

Diabetes causes a person’s blood sugar to be too high

In all cases of diabetes, a person’s blood sugar is too high. The pancreas typically produces insulin that helps turn glucose from food into energy for a person’s cells. In type 1 diabetes, the body does not produce insulin. This is usually diagnosed in children and teens. People with type 1 diabetes must take insulin to survive.

People with type 2 diabetes can’t make or use their own body’s insulin well. It can occur at any age, but typically develops later in life. This can sometimes be controlled with diet and exercise, but also sometimes needs medication.

Gestational diabetes develops in women when they are pregnant. It includes women who have elevated blood sugar before pregnancy but are not recognized until blood sugar screening test during pregnancy.

 Dr. Xiang noted that more research needs to be conducted to understand the mechanism for the association between maternal diabetes and ADHD, particularly the role of blood sugar levels throughout pregnancy.

Message to patients: work with your doctor

Both Dr. Xiang and the senior author on the research, and obstetrician-gynecologist Klara Feldman, MD, from the Kaiser Permanente Baldwin Park Medical Center, agreed that the research emphasizes the importance of working with clinicians to maintain good control of blood sugar levels throughout pregnancy.

Dr. Feldman added that it also highlights how critical it can be for a woman to see her doctor before she gets pregnant. Often women don’t go to their doctors until after they become pregnant, she said.

“This research adds to a growing body of evidence that suggests that a woman should see her doctor when she is considering becoming pregnant. In particular, if a woman has diabetes, she should work to get good control of her blood sugars before pregnancy, and if she hasn’t been diagnosed with diabetes she will want to get tested,” Dr. Feldman said. “A mother’s control of her diabetes is very important for her baby, and preconception counseling allows us to work though many of the questions and challenges and helps moms to be on the best path to having a healthy baby.”

Research into maternal diabetes will continue

Dr. Xiang said she would continue to work to determine if a mother’s diabetes also influences a child’s risk of other neurological developmental disorders.

“A lot of disease tracks back to conditions during pregnancy,” she said. “Major work previously looked at childhood obesity. We have now developed a large enough store of electronic medical records over many years at Kaiser Permanente Southern California to evaluate the potential effect of the intrauterine environment on a child’s neurological development and other health outcomes, including autism and ADHD.”

Dr. Xiang said she would next look at development delay and disability. After that, possibly asthma risk.

In addition to Dr. Xiang and Dr. Feldman, other researchers on the study were Xinhui Wang, PhD, Mayra Martinez, MPH, and Darios Getahun, MD, PhD, of the Department of Research & Evaluation, and Kathleen Page, MD, and Thomas Buchanan, MD, of the Keck School of Medicine at the University of Southern California.