People with a “glass half empty” attitude to life may be at a higher risk of premature death, research suggests.
Scientists from The QIMR Berghofer Medical Research Institute in Brisbane looked at the results of nearly 3,000 people aged over 50 who completed a test measuring optimism.
Twenty years later, those who scored the most pessimistic were up to 30% more likely to have died from any cause or heart disease specifically.
Although unclear, it has been suggested more hopeful people tend to lead healthier lifestyles.
‘Pessimism affects mortality’
The participants completed The Life Orientation Test between 1993 and 1995.
They were asked the extent to which they agree with statements like, “I'm a believer in the idea ‘every cloud has a silver lining’” and “if something can go wrong for me, it will”.
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Around 20 years later, they were matched against information from the Australian National Death Index, with 1,068 out of the 2,978 participants having died.
Results, published in the journal Scientific Reports, revealed the most pessimistic individuals were 30% more likely to have passed away during the follow-up period than the least despondent participants.
On average, the least pessimistic individuals lived 1.8 years longer than their gloomier counterparts.
The results remained the same after the scientists adjusted for any depression diagnosis.
No link was found between a participant’s outlook on life and their risk of dying from cancer.
“We consider that pessimism affects mortality, rather than ill-health leading to pessimism, because the association was found for cardiovascular deaths and deaths from ‘other causes’ but not from cancers,” wrote the scientists.
Optimists ‘less likely to smoke and have better diets’
Perhaps surprisingly, while being pessimistic was linked to premature death, being optimistic does not appear to help people live longer.
The scientists argue optimism and pessimism are “not direct opposites”.
“They change in the same direction with age rather than one going up as the other goes down,” they wrote.
The results support a 2016 study by a team at Päijät-Häme Central Hospital in Finland, which found pessimists were more than twice as likely to die from coronary heart disease than their more upbeat counterparts.
Scientists from Mount Sinai St Luke’s Hospital in New York later discovered optimism reduced the risk of dying from heart disease by 35% and any cause by 14%.
Lead author Dr Alan Rozanski noted optimistic people are “more likely to exercise”.
“They’re less likely to smoke,” he said, as reported in The Science Times. “They have better diets.
“They watch their weight better. That is, by the way, one of the key mechanisms, perhaps the most important mechanism, but certainly one of the key mechanisms.”
The Australian scientists noted their participants’ pessimism ratings were measured just once and “depend on the assumption the scores represent characteristics with long-term stability”.
Nevertheless, they wondered whether people could be “trained out of pessimism”, with previous interventions focusing on boosting optimism.