VIENNA — Children whose parents are particularly old or young have a greater risk of suffering from bipolar disorder, reveal scientists in a new study. The 13-million-person review shows that mothers older than 35 or fathers over 45 are more likely to have a child suffering from the depressive condition. Likewise, giving birth under 20 makes your child more likely to have the disorder.
These results create a U-shaped curve, say scientists at the European College of Neuropsychopharmacology (ECNP), who say it’s “unusual” that both young and old parents carried the higher risk. They speculate younger parents might have the increased chances because of financial issues and stress. Meanwhile, older parents may carry genetic risk factors.
Bipolar disorder is a serious mental illness where sufferers swing from extreme highs and overactivity known as mania, to very lethargic lows or depression. Unlike most mood swings, bipolar episodes last weeks. It remains one of the most common serious mental illnesses, affecting around two percent of people, and carries a high risk of suicide and premature death. Sufferers are 10 to 30 times more likely to take their own lives than the rest of the population, according to the National Library of Medicine.
Bipolar is a highly inheritable disorder: if one parent has it there’s a 15 to 30 percent chance the child will. This research presented at ECNP Congress in Vienna opens up new ways to understand bipolar passing through generations.
“Parental age is a factor which affects many conditions, such as fertility and some neuropsychiatric disorders. What we have found is slightly unusual because both younger and older parents carry an increased risk of having a child with bipolar disorder,” says study leader Dr. Giovanna Fico, of the University of Barcelona, in a statement. “The increased risk is moderate, but real. We can speculate that younger parents may be affected by environmental factors, such as socio-economic problems, lack of support, but also stress or immunological factors, and that older parents may have genetic factors coming into play, but the truth is we don’t really know.”
The researchers reviewed studies from various countries relating bipolar disorder to age. The massive dataset included 13,424,760 participants of whom 217,089 had the condition.
Results show that older men had a higher risk of having a bipolar child — 29 percent higher than fathers aged 25 to 29. Older women had 20 percent higher odds than mothers aged 25 to 29. Parents younger than 20 were 23 percent more to likely to have a bipolar child.
“Again, we must stress that this risk is moderate, and it must be kept in perspective. However, for those already at risk, age is another factor that should be taken into consideration, and so it may be that doctors need to counsel both younger and older couples if they have a risk of bipolar disorder,” says Fico. “We also see this U-shaped curve in some other conditions, such as autism and some cardiovascular diseases. We are planning to study several environmental factors which might be related to the risk of bipolar disorder, but also to its course of illness. For example, we would like to explore how the exposure to pollution, climate changes, urbanization might affect the risk of some psychiatric disorders, and we want to try to understand if these factors help or worsen the course of the disorder.”
Though not involved in the research, Professor Maj Vinberg from University of Copenhagen, says this research could pave the way to early prevention and intervention tactics. “The study raises several exciting research questions, including the possibility of early prevention and intervention,” she notes. “For example, in the daily clinical settings, it is crucial to be aware that young individuals with BD in their manic phases have more risky sexual behavior, which can associate with an increased pregnancy risk.”
Report by South West News Service writer Pol Allingham.