Researchers found that children whose mothers developed gestational diabetes are at an increased risk for attention deficit hyperactivity disorder (ADHD) at age 6, especially if they are from families with low socioeconomic status.…
According to the lead researcher, Yoko Nomura, PhD, of Queens College in Flushing, N.Y., and colleagues, maternal gestational diabetes was associated with a two-fold increase in ADHD risk by the time the child is 6 (OR 2.20, 95% CI 1 to 4.82, P=0.05),
But the risk rose more than 14-fold for children of affected mothers when the family lived in low socioeconomic conditions (OR 14.31, 95% CI 2.14 to 95.88, P=0.006), the researchers reported online in Archives of Pediatric and Adolescent Medicine.
Gestational diabetes arises at a time of critical brain development in the fetus, but little is known about the long-term consequences of this on the child’s later neurologic and behavioral development.
To explore these concerns and to see if socioeconomic status conferred additional risk, Nomura and colleagues analyzed data from an ongoing cohort study of 212 children, who were enrolled at around 4 years of age. The cohort was largely middle class, ethnically diverse, and predominantly male.
A total of 10% of the mothers reported having developed gestational diabetes while pregnant with the child enrolled in the study.
At baseline, the mean inattention scores were higher for children whose mothers had gestational diabetes (12.25 versus 9.50, P=0.05), although differences were not seen for hyperactivity/impulsivity scores (12.58 versus 11.29, P=0.36). But in children of low socioeconomic status, both inattention and hyperactivity scores were higher (11.96 versus 9.79, P=0.01, and 13.23 versus 10.65, P=0.01).
Low socioeconomic status alone was associated with a two-fold increase in ADHD risk both at baseline (OR 1.87, 95% CI 1.21 to 2.89, P=0.005) and at 6 years (OR 2.41, 95% CI 1.53 to 3.79, P<0.001).
The researchers then compared development in children who were exposed to both maternal diabetes and low socioeconomic status, those exposed to diabetes alone, those exposed to low socioeconomic status alone, or neither. They found that on neuropsychological function testing at baseline, children with both exposures fared worse in language (P<0.001), memory (P=0.005), and visuospatial function (P=0.001). They also had worse scores for inhibition (P<0.001), levels of activity (P=0.04), persistence (P<0.001), and impulsivity (P=0.003).
By age 6, children with both exposures were less adaptable (P=0.04), had poorer functional communication (P=0.009), greater attention difficulties (P=0.004), were more withdrawn (P=0.05), and more depressed (P=0.03).
When children with only one exposure were compared with those having neither exposure, no increased risk for ADHD at age 6 was seen.
But the increased risk seen for those with both exposures was “substantial,” and a statistical test determined that 82% of this risk could be attributed to the synergistic effects of maternal gestational diabetes and low socioeconomic status, the researchers explained.
Precisely how these factors interact is not known. However, “practitioners in internal medicine, endocrinology, obstetrics, and pediatrics should be alerted so that there can be multiple points of intervention to prevent the development of neuropsychological dysfunction in offspring,” they cautioned.
They also noted that ADHD has a strong genetic — and therefore not modifiable — component, which further heightens the importance of minimizing potentially modifiable environmental factors.
“It is clear that developing a refined understanding is urgently needed among expectant mothers regarding certain risk-prone behaviors (overeating, poor diet, and smoking during pregnancy) to mitigate the long-term human and economic costs,” they stated.
- Children in the study were first seen at age 4 and the history of gestational diabetes was by maternal report.
- Exposure to both gestational diabetes and low socioeconomic status greatly increased the risk of a diagnosis of attention-deficit/hyperactivity disorder (ADHD) and other neurocognitive difficulties by age 6.
Nomura Y, et al “Exposure to gestational diabetes mellitus and low socioeconomic status: effects on neurocognitive development and risk of attention-deficit/hyperactivity disorder in offspring” Arch Pediatr Adolesc Med 2012.