Could high blood pressure-related complications during pregnancy be tied to thinking skills in children years later?

A study from Denmark hints at “a modest association” between such complications and poorer reasoning, intuition, and perception skills in young adult men, report Dr. Vera Ehrenstein, at Aarhus University Hospital, and colleagues.

The study compared intelligence tests measures for more than 17,000 men drafted into Danish military service. Of these men, tested at the age of 19, about 15 percent had poor thinking skills, measured by IQs below 85, the researchers report in the American Journal of Epidemiology.

The mothers of about 5 percent of the men in the study had either blood pressures above 140/90, protein in the urine, or swelling of the extremities. All of those are signs or symptoms of a life-threatening condition known as pre-eclampsia.

Poorer thinking skills were slightly more common among men whose mothers had any of those signs or symptoms. About 19 percent of the adults of affected mothers had poorer thinking skills, versus 15 percent among those whose mothers were not affected.

When the researchers accounted for being born small, which places infants at risk for delayed or impaired brain development, and for other factors, poor thinking skills were still as much as a third more likely among men whose mothers suffered from pre-eclampsia symptoms.

Ehrenstein’s team notes the current findings cannot determine whether high blood pressure-related complications of pregnancy cause poorer thinking skills, nor why such complications would have any effect on those skills.

SOURCE: American Journal of Epidemiology, October 15, 2009.