Role of Excessive Weight Gain During Gestation in the Risk of ADHD in Offspring of Women With Gestational Diabetes

Context Although attention-deficit/hyperactivity disorder (ADHD) has been associated with gestational diabetes mellitus (GDM) and maternal obesity, excessive weight gain (EWG) during pregnancy has scarcely been evaluated. Objective This study aimed to assess the joint effect of maternal weight and EWG on the risk of ADHD in offspring of GDM pregnancies. Methods In this cohort study of singleton births >22 weeks of gestation of women with GDM between 1991 and 2008, gestational weight gain above the National Academy of Medicine (NAM) recommendations was classified into EWG. Cox-regression models estimated the effect of maternal pregestational weight and EWG on the risk of ADHD (identified from medical records), adjusted for pregnancy outcomes and GDM-related variables. Results Of 1036 children who were included, with a median follow-up of 17.7 years, 135 (13%) were diagnosed with ADHD. ADHD rates according to pregestational maternal weight were 1/14 (7.1%) for underweight, 62/546 (11.4%) for normal weight, 40/281 (14.2%) for overweight, and 32/195 (16.4%) for obesity. Only maternal obesity was independently associated with ADHD (HRadjusted 1.66 [95% CI, 1.07-2.60]), but not maternal overweight or EWG. On evaluating the joint contribution of maternal weight and EWG, maternal obesity with EWG was associated with the highest risk of ADHD (vs normal weight without EWG; HRadjusted 2.13 [95% CI, 1.14-4.01]). Pregestational obesity without EWG was no longer associated (HRadjusted 1.36 [95% CI, 0.78-2.36]). Conclusion Among GDM pregnancies, pregestational obesity was associated with a higher risk of ADHD in offspring. Nonetheless, when gestational weight gain was taken into account, only the joint association of obesity and EWG remained significant.

Automated summary

This study found that pregestational obesity is associated with a higher risk of ADHD in offspring of GDM pregnancies. However, excessive weight gain during pregnancy does not have an independent effect on ADHD risk. Only the joint association of obesity and excessive weight gain during pregnancy remains significant in relation to ADHD risk.