Search Here

Forget women, men also have a biological clock. New research reveals the risk of psychiatric and academic problems among children of older fathers is greater than previously thought.

After examining data of everyone born in Sweden from 1973 to 2001, researchers found a strong correlation between advancing paternal age at childbearing and various psychiatric disorders and educational problems in their children. Researchers explained that children of older fathers are more likely to have autism, ADHD, bipolar disorder, schizophrenia, suicide attempts and substance abuse problems. They were also more likely to fail their classes, score low on IQ tests and not finish school.

"We were shocked by the findings," Brian D'Onofrio, lead author and associate professor in the Department of Psychological and Brain Sciences in the College of Arts and Sciences at Indiana University Bloomington, said in a news release. "The specific associations with paternal age were much, much larger than in previous studies. In fact, we found that advancing paternal age was associated with greater risk for several problems, such as ADHD, suicide attempts and substance use problems, whereas traditional research designs suggested advancing paternal age may have diminished the rate at which these problems occur."

The findings revealed that a child born to a 45-year-old father is 3.5 times more likely to have autism, 13 times more likely to have ADHD, two times more likely to have a psychotic disorder, 25 times more likely to have bipolar disorder and 2.5 times more likely to have suicidal behavior or a substance abuse problem, compared to a child born to a 24-year-old father.

Researchers said the risk of these disorders increased steadily with advancing paternal age. Researchers said this means that there is no particular paternal age at childbearing that suddenly becomes problematic.

When researchers compared siblings, they found that the associations with advancing paternal age were much greater than estimates in the general population.

"The findings in this study are more informative than many previous studies," D'Onofrio said. "First, we had the largest sample size for a study on paternal age. Second, we predicted numerous psychiatric and academic problems that are associated with significant impairment. Finally, we were able to estimate the association between paternal age at childbearing and these problems while comparing differentially exposed siblings, as well as cousins. These approaches allowed us to control for many factors that other studies could not."

"While the findings do not indicate that every child born to an older father will have these problems, they add to a growing body of research indicating that advancing paternal age is associated with increased risk for serious problems. As such, the entire body of research can help to inform individuals in their personal and medical decision-making," he concluded.

The findings are published in the journal JAMA Psychiatry.