Older paternal age has been linked to a higher risk of complex neurodevelopmental disorders, including schizophrenia and autism. Now a Swedish study of 80,568 people has also linked older fathers to an increased likelihood of bipolar disorder. Researchers compared 13,428 people with bipolar to 67,140 controls and found that people with fathers over the age of 29 were at an increased risk of developing the condition. The offspring of fathers over the age of 55 were found to have a 37% higher risk than those of fathers who were between 20 and 24. The offspring of older mothers also had an increased risk but it was less-pronounced than that of having an older father.
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