Father's Age Linked to Mental Illness Risk in Children

Father's Age Linked to Mental Illness Risk in Children

When it comes to family planning, it’s usually women that hear the cacophony of their biological clocks. But maybe potential dads-to-be should pay attention to that ticking as well. Research is suggesting that children born to older fathers have a higher risk for schizophrenia and other mental health problems, such as bipolar disorder, autism and ADHD.

In one large study, researchers from Indiana University and the Karolinska Institute studied medical and educational records covering nearly every child born in Sweden between 1973 and 2001. The numbers they found were suprising. Children born to fathers over the age of 45 were twice as likely to have psychotic disorders such as schizophrenia, and 25 times more likely to develop bipolar disorder. They also were 13 times more likely to be diagnosed with ADHD and three and a half times more likely to develop autism. For most conditions, the risk rose steadily with the father’s age.

Another large study, this one using Danish health registers to look at nearly three million kids, found that fathers over age 29 were more likely to have children with a mental disorder, especially schizophrenia, autism and mental retardation. Both studies were published in JAMA Psychiatry.

Other research has found similar trends in older mothers, as well. Women are born with all the eggs they’ll ever have, and as they age, the quality of those eggs declines, allowing for more genetic errors. Researchers believe a similar process could happen in men: As men get older, their sperm contain more errors, which then could lead to mental illnesses in their offspring.

Of course, these studies don’t prove that theory is correct, and the researchers note that most children of older dads won’t have psychiatric problems.

Related: Fertility Improvement Plan for Potential Dads-to-Be

Counting the risks
If nothing else, these findings fill in another small piece in the diagnostic puzzle of mental illnesses like schizophrenia, although much is still unknown. Here’s what mental health experts do know:

  • Genetics – Genes are a big risk factor for determining whether or not someone will develop schizophrenia. Your risk for schizophrenia jumps from 1 to 10 percent if your mother, father or sibling has the disorder. If you have two parents or an identical twin with schizophrenia, your risk could be as high as 65 percent.
  • Brain chemistry – People diagnosed with schizophrenia tend to have an abnormal imbalance of neurotransmitters in the brain. The messengers between the brain’s nerve cells, as well the pathways that carry brain chemicals such as dopamine, are often disrupted or damaged in patients with the disorder.
  • Environment – Many environmental factors could be involved, including exposure to certain types of viruses, malnutrition before birth, complications during pregnancy and childhood trauma like physical or sexual abuse.

Medically reviewed in April 2020.

What We Know About the Causes of Schizophrenia
What We Know About the Causes of Schizophrenia
Schizophrenia—a mental illness that typically distorts a person’s perception of reality—affects less than one percent of the US population.  Although ...
Read More
Why is schizophrenia such a serious illness?
Mark Moronell, MDMark Moronell, MD
Schizophrenia is a serious illness that can completely incapacitate people, causing social isola...
More Answers
Can a person have more than one type of schizophrenia?
Douglas E. Severance, MDDouglas E. Severance, MD
Sometimes, people with schizophrenia experience several groups of symptoms at the same time. Whe...
More Answers
What Are Common Side Effects with Schizophrenia Medication?
What Are Common Side Effects with Schizophrenia Medication?