Individuals with higher levels of neuroticism -- a personality trait associated with negative emotions -- are likely to have a longer lifespan and lower risk of mortality, regardless of their health conditions, a study has claimed.

Persons with high levels of neuroticism are more likely to experience negative emotions -- including irritability, frustration, nervousness, worry, and guilt -- compared with those who have lower levels of neuroticism.

"Our findings are important because they suggest that being high in neuroticism may sometimes have a protective effect, perhaps by making people more vigilant about their health," said lead researcher Catharine R. Gale from the University of Edinburgh.

The findings showed that higher neuroticism is linked with slightly lower risk of death from all causes and cancer.

However, "we found that this protective effect was only present in people who rated their health as fair or poor", Gale explained.

"We found that people who scored high on one aspect of neuroticism related to worry and vulnerability had a reduced risk of death regardless of how they rated their health," Gale said.

For the study, published in the journal Psychological Science, the team examined data collected from 502,655 people aged between 37 and 73. 

Participants completed a validated personality assessment measuring neuroticism and indicated whether they thought they were in excellent, good, fair or poor health overall.

The data also included information on participants' health behaviours (smoking, physical activity), physical health (body mass index, blood pressure), cognitive function, and medical diagnoses (heart problems, diabetes, cancer).