Boys More Vulnerable to Hyperactivity Disorder (ADHD) than Girls

In a study conducted by a team of scientists under the leadership of Xiaobin Wang, MD, MPH, ScD, the director of the Center on the Early Life Origins of Disease in the Department of Population, it was established that individuals who have higher levels of lead in childhood blood have higher chances of developing ADHD. The study further revealed that the boys were the most vulnerable. These findings were established after Wang and her colleagues analyzed data from 1479 mother-infant pairs. 299 of these pairs comprised of a child with ADHD while 1180 others were neurotypical children.

How the Study was done

To conduct the study, Wang and colleagues made use of electronic medical records in order to get the measurements of lead in the child’s first blood as well as the diagnosis of ADHD by the physician. The researchers also did multiple logistic regression and graphic plots to evaluate the links between dose-response and the condition. The potential effect of modifiers was also analyzed.

“After the removal of lead from gasoline and paints, exposure to lead has declined significantly over the past few years. However, that hasn’t stopped the metal from spreading in low-income populations,” explained Wang and colleagues to the MD Magazine.

The study was done in the Boston Birth Cohort and established that at least 8.9% of children in this area had about 5-10 ug/dL lead levels.

Boys at Higher Risk

Wang completely opposed the ideology that there are safe low levels of lead, explaining that their evidence suggested that no given amount of lead can be said to be safe. An 8.9% lead levels could cause an increase in risk to ADHD by about 66%.

Furthermore, significant gender differences were also spotted. In boys, for example, the lead-ADHD association increase risk by 149%. “The association in girls was mainly attenuated, which suggests that boys are more vulnerable to lead exposure than the boys.”

The mother also played a significant role with respect to how much lead could be detected in the child. For mothers who had higher amounts of lipoproteins, their children recorded lower blood lead levels. This fact could be seen when the mother had low stress during stress.

According to Wang and colleagues, these findings further assist us to understand the gender differences with regard to ADHD and also gives a clear picture of how it can be prevented.

The study was published in The Journal of Pediatrics.