NEW YORK: People with a positive outlook on life may be less likely than pessimists to experience events like a heart attack or stroke, and they may live longer, a recent review of existing research suggests.
For the analysis, researchers examined data from 15 studies with a total of 229,391 participants who were followed for an average of about 14 years.
During that time, the most optimistic people were 35 per cent less likely than the least optimistic to have cardiovascular events like heart attacks or strokes, and 14 per cent less likely to die for any reason, researchers report in JAMA Network Open.
"These results suggest that positive and negative mindsets not only affect one's quality of life but may be related to one's health as well," said Dr Alan Rozanski, lead author of the study and a researcher at the Icahn School of Medicine at Mount Sinai in New York City.
Optimists may have better health habits that help them live longer, Rosanski said by email. They may eat better, exercise more and smoke less than pessimists, for example, as well as better coping skills to help them be proactive about their health and manage tough times without turning to unhealthy behaviors.
Pessimism, by contrast, may take a toll on the body by increasing inflammation and making people more likely to develop metabolic abnormalities that can cut life short, Rosanski noted.
While many studies over the past few decades have linked stress and mood disorders to an increased risk of heart disease, the results offer fresh evidence that people's outlook on life may also impact heart health.
"Optimism has long been linked to better performance in school and in such jobs as sales, sports, political endeavours, and social relationships, but it's also an important health issue that has not been well studied until now," Rozanski said.
Ten of the studies in the current analysis focused on the link between optimism and events like heart attacks and strokes, while nine studies looked at deaths from all causes.
To assess whether participants were optimistic, many of the studies used what's known as a life orientation test that asks people to answer six standard questions regarding their thoughts about the future.
Among other things, questions focused on whether people expect the best in uncertain times, or whether people expect things to go their way.
In their analysis, researchers accounted for risk factors for heart disease and premature death like depression and inactivity.
One limitation of the study is that the smaller studies in the analysis included a wide variety of ages, from teens to elderly adults, which could influence the likelihood of heart attacks or strokes.
It is also unclear whether optimism is a trait people can change to potentially improve their heart health, or whether it is something they are born with that is not possible to alter, said Dr Jeff Huffman, director of the Cardiac Psychiatry Research Program at Massachusetts General Hospital in Boston, who wrote an editorial accompanying the study.
"There is increasing evidence that positive psychology programmes that help people to cultivate skills in experiencing positive emotions might indeed work," Huffman said by email.
"These programmes train people to imagine a better future, to savor positive things when they happen, and to use their strengths when taking on a challenge," Huffman said. "But we don't yet know if they will prevent heart disease."