Excessive worry and stress can cause premature death, partly because chronic worriers could adopt unhealthy behaviours like smoking , researchers said.
In this study, the researchers from Purdue University looked at how smoking and heavy drinking are associated with the trait.
"Research shows that higher levels of neuroticism can lead to earlier mortality, and we wanted to know why," said Daniel K. Mroczek, a professor of child development and family studies.
"We found that having worrying tendencies or being the kind of person who stresses easily is likely to lead to bad behaviours like smoking and, therefore, raise the mortality rate.
"This work is a reminder that high levels of some personality traits can be hazardous to one's physical health," he added.
Researchers suggest that a person with high neuroticism is likely to experience anxiety or depression and may self-medicate with tobacco, alcohol or drugs as a coping mechanism.
The study showed that smoking accounted for about 25 percent to 40 percent of the association between high neuroticism and mortality.
The other 60 percent is unexplained, however, it is possibly attributed to biological factors or other environmental issues that neurotic individuals experience, Mroczek added.
Mroczek said that a better understanding of the bridge between personality traits and physical health can perhaps help clinicians improve intervention and prevention programs.
"For example, programs that target people high in neuroticism may get bigger bang for the buck than more widespread outreach efforts," he said.
"It also may be possible to use personality traits to identify people who, because of their predispositions, are at risk for engaging in poor health behaviors such as smoking or excessive drinking," he added.
The findings are published in Journal of Research in Personality.