Children of older fathers more likely to have bipolar disorder

September 1, 2008

Older age among fathers may be associated with an increased risk for bipolar disorder in their offspring, according to a report in the September issue of Archives of General Psychiatry.

Bipolar disorder is a common, severe mood disorder involving episodes of mania and depression, according to background information in the article. Other than a family history of psychotic disorders, few risk factors for the condition have been identified. Older paternal age has previously been associated with a higher risk of complex neurodevelopmental disorders, including schizophrenia and autism.

Emma M. Frans, M.Med.Sc., of the Karolinska Institutet, Stockholm, Sweden, and colleagues identified 13,428 patients in Swedish registers with a diagnosis of bipolar disorder. For each one, they randomly selected from the registers five controls who were the same sex and born the same year but did not have bipolar disorder.

When comparing the two groups, the older an individual's father, the more likely he or she was to have bipolar disorder. After adjusting for the age of the mother, participants with fathers older than 29 years had an increased risk. "After controlling for parity [number of children], maternal age, socioeconomic status and family history of psychotic disorders, the offspring of men 55 years and older were 1.37 times more likely to be diagnosed as having bipolar disorder than the offspring of men aged 20 to 24 years," the authors write.

The offspring of older mothers also had an increased risk, but it was less pronounced than the paternal effect, the authors note. For early-onset bipolar disorder (diagnosed before age 20), the effect of the father's age was much stronger and there was no association with the mother's age.

"Personality of older fathers has been suggested to explain the association between mental disorders and advancing paternal age," the authors write. "However, the mental disorders associated with increasing paternal age are under considerable genetic influence." Therefore, there may be a genetic link between advancing age of the father and bipolar and other disorders in offspring.

"As men age, successive germ cell replications occur, and de novo [new, not passed from parent to offspring] mutations accumulate monotonously as a result of DNA copy errors," the authors continue. "Women are born with their full supply of eggs that have gone through only 23 replications, a number that does not change as they age. Therefore, DNA copy errors should not increase in number with maternal age. Consistent with this notion, we found smaller effects of increased maternal age on the risk of bipolar disorder in the offspring."

Source: JAMA and Archives Journals

Explore further: Having parents with bipolar disorder associated with increased risk of psychiatric disorders

Related Stories

Young adults may outgrow bipolar disorder

September 29, 2009

Bipolar disorder, or manic-depression, causes severe and unusual shifts in mood and energy, affecting a person's ability to perform everyday tasks. With symptoms often starting in early adulthood, bipolar disorder has been ...

Recommended for you

How the finch changes its tune

August 3, 2015

Like top musicians, songbirds train from a young age to weed out errors and trim variability from their songs, ultimately becoming consistent and reliable performers. But as with human musicians, even the best are not machines. ...

Machine Translates Thoughts into Speech in Real Time

December 21, 2009

( -- By implanting an electrode into the brain of a person with locked-in syndrome, scientists have demonstrated how to wirelessly transmit neural signals to a speech synthesizer. The "thought-to-speech" process ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

not rated yet Mar 10, 2009
I think older fathers being less involved with nurturing children is a more logical correlation, than accumulated mutations. The accumulated mutations should be linked to general birth defects, for example.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.