(CBS Atlanta) — A recent study out of Sweden has revealed that younger siblings are more likely to commit suicide than firstborns or older siblings.
The study, published in the American Journal of Epidemiology, says that in adulthood there is an 18 percent increase in suicide risk for every increase in birth order, such as from firstborn to second-born.
According to Live Science, the study does not explain causality, meaning that there is simply a link between birth order and suicide risk, but the cause for this is not yet known.
In the study, Mikael Rostila and colleagues pulled birth and death records from Swedish national registries between 1931 and 1980. Controlling for sex, birth year and mother’s age at delivery, Rostila found that suicide risk increased the later a sibling’s birth order.
“Our findings are important, since they highlight that birth order should be considered an early-life circumstance that determines mental health across the life course,” says Rostila, who is also the study leader and a sociologist at Stockholm University’s Centre for Health and Equity Studies.
Rostila’s research also found that younger siblings may be more risk-prone or impulsive after results linked an increased risk of dying from an accident with higher birth order. However that link was not as strong as the link with suicide.
This study seems to support other research as well, namely another study published in the American Journal of Epidemiology in 2013 that found that for each increase in birth order, a sibling’s suicide risk jumped 46 percent.
While this particular study took place in Sweden, the U.S.’ Centers for Disease Control and Prevention found that as recently as 2009, suicide was the 10th leading cause of death among persons ages 10 years and older, surpassing the number of deaths from motor vehicle crashes and accounting for 35,891 deaths that year.
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