Previous studies have made doctors concerned with mothers giving birthday at an older age. Now, a new study from Indiana University in Bloomington suggests that children of older fathers may be more susceptible to developing psychiatric problems than children born to younger fathers.
Published in the journal JAMAPsychiatry, fathers who have a child after the age of 45 may face a significantly increased risk; their offspring having mental health and academic problems including autism, ADHD, schizophrenia, suicidal ideation, low IQ scores and failing grades.
The researchers examined the births in Sweden over a 28-year period, from 1973 to 2001. They compared children who had been born to older fathers, their older siblings to test how much of an influence the age of the father at conception.
After comparing family members, the following risks were estimated:
- Attention-deficit/hyperactivity disorder
- Bipolar disorder
- Suicide attempt
- Substance abuse
- Low educational attainment
The study found that children born to fathers 45 years or older were at higher risk of developing all of these problems, compared to their siblings who were born when their fathers were between 20 and 24 years of age. The offspring was 25 times more likely to have bipolar disorder, 13 times more likely to have ADHD, 3.5 times more likely to have autism, 2.5 times more likely to exhibit suicidal behavior or substance abuse problem, and twice as likely to have a psychotic disorder, compared to a 24-year-old father.
Sibling-based comparison studies do have limitations and can provide some defective information. This type of study also assumes that all of the children in a family are exposed to the same conditions growing up, when this might not be the case.
The researchers, however, feel confident that their sibling-comparison results are consistent with the believe that genetic mutations are caused by advanced parental age during fertilization.
"Regardless of whether these results should lead to policy changes, clarification of the associations with (advanced aging in dads) would inform future basic neuroscience research, medical practice, and personal decision-making about childbearing," the researchers concluded.