Kids born to fathers older than 30 stand a higher chance of developing bipolar disorder, Swedish researchers disclosed on Monday.

About 14,500 people with the mental disorder have been compared to an estimated 67,000 people without the condition. After taking into consideration the number of children, maternal age, socioeconomic status and family history of psychotic disorders, researchers found that the children of men older than 55 were 1.37 times more likely to develop bipolar disorder than the children of men aged 20 up to 24 years, said Emma M. Frans, MmedSc, of the Karolinska Institute in Stockholm, and her co-workers. In other words, the offspring included in the first category had a 37 percent greater risk for the mood disorder, compared to the offspring from the second category.

According to The Washington Post, children of older mothers were also found at risk of being diagnosed as having the condition, but this risk was less prominent than the risk associated with more mature fathers. The results of the study, which was published in the September issue of the journal Archives of Psychiatry, also show that, when individuals are diagnosed with bipolar disorder at an early age, meaning before 20, the impact of the father's age is higher, whereas the mother's age doesn’t present the slightest correlation.

"Personality of older fathers has been suggested to explain the association between mental disorders and advancing paternal age,” the authors of the study said. “However, the mental disorders associated with increasing paternal age are under considerable genetic influence."

As maintained by some experts, the findings of the research aren’t that convincing so that paternal age could be somehow linked to the bipolar disorder, a serious mental illness characterized by the concomitant presence of mania and depression, Chicago Tribune reported.