Hypertension in Pregnancy Related to Risk of ADHD in Child
FEBRUARY 19, 2017
Mothers who experienced a hypertensive disorder such as eclampsia during pregnancy reported an almost twofold increased risk of attention-deficit/hyperactivity disorder (ADHD) in their children.
A new analysis from the Millennium Cohort Study (MCS) of over 13,000 mother-child pairs, suggested their association remained even after analysis for multiple potential confounders, including: maternal demographics and health, smoking or alcohol consumption during pregnancy, parity, duration of term, and birth weight.
While there has been strong evidence that ADHD can be inherited, with several genetic variants implicated, the investigators considered whether a gene-environment interaction in utero could also contribute to this increase. The team also posited whether fetal exposure to a hypertensive disorder of pregnancy posed such risk.
"Given that the in utero environment is a critical determinant of neurodevelopmental outcome, a number of pre- and perinatal risk factors have been suggested to increase the risk of ADHD in affected children," explained Ali Khashan, PhD, Department of Epidemiology and Public Health, University College Cork, Cork, Ireland, and colleagues.
The MCS was initiated in the United Kingdom in 2001, with families surveyed when the child was 9 months of age, and again at age 3, 5, 7, and 11 years of age. The presence of a hypertensive disorder of pregnancy was determined from questioning about problems during pregnancy, including terms such as "raised blood pressure" and "eclampsia" or "preeclampsia".
The survey included the question of whether a diagnosis of ADHD had been received from a health professional, and provided the Strength and Difficulties Questionnaire (SDQ) to ascertain parent-reported behavioral difficulties. A score of seven points or greater on the 10 point SDQ subscale on hyperactivity issues provided additional indication of the disorder.