A study undertaken by Indiana University in Bloomington has indicated that children born of older fathers are at higher risk of developing psychiatric disorders compared to those born of younger fathers.
A previous study showed that children with older fathers were at higher risk of schizophrenia, bipolar disorder, autism, intellectual problems and academic problems. Genetic studies have indicated that the father’s age at conception could be linked to the development of ‘de novo mutations.’ These mutations occur when a gene appears for the first time in a family due to the mutation of the sperm or the egg from one of the parents. The mutations have been linked to autism spectrum disorders.
It is the first time a comprehensive study has been done to try and discover the association of ‘advancing paternal age’ and psychiatric issues.
Swedish Study Over 28 Years
This study was based on a large population which included everyone born in Sweden during the 28-year period from 1973 to 2001. To test the influence of the father’s age at conception, researchers compared diagnostics from children who had been born to aged fathers with older siblings who were born when the father was of a younger age.
Once the comparison of these family members had been completed, researchers estimated the risks related to autism, psychosis, bipolar disorder, substance abuse, attention-deficit disorder, low education attainment and suicide attempt.
The results indicated that children whose fathers were 45 years and older were at more risk of developing all the mentioned problems, compared to their siblings who were born when the fathers were between the ages of 20 and 24 years old.
By making use of siblings, the researchers were able to eliminate environmental and genetic influences that may have caused one child to have a higher risk of developing these disorders.
However, it has been found that sibling-based studies for comparison purposes has limitations and the data derived from it may be unreliable.
The order in the family may have an effect on the psychological development of a child. The conditions of the family and the environment during the child’s formative years could also affect the development.
In this instance, the researchers feel confident that their methods of sibling-based comparisons are consistent.