heart disease who are more upbeat and excited tend to live longer than those
who don't have such a positive outlook, a new study suggests, possibly because
they are often more active.
surveyed people with ischemic heart disease – when the heart doesn't get enough
blood due to narrowed arteries – and found earning a high score on measures of
"positive affect" was tied to a greater chance of being a regular
exerciser and a lower risk of dying over the next five years.
adds to the body of literature suggesting that there may be relationships
between positive affect... and all-cause mortality," Richard Sloan, who
studies psychological risk factors and heart disease at Columbia University
Medical Centre in New York, said.
"But it's going to take more than this
to be confident that there's a link in the way we're confident there's a link
between depression and (a higher risk of) heart disease," Sloan, who
didn't participate in the new research, told Reuters Health. The new study
included 607 heart patients who were seen at one Danish hospital.
Quality of life
Pedersen from Tilburg University in The Netherlands and her colleagues asked
the patients about their quality of life, mood and lifestyle habits including
physical activity in 2005. Then they used death and hospital records to track
participants through 2010.
On a mood scale ranging from 0 to 40, where higher
scores indicate feeling more relaxed, self-confident and excited, half of
participants scored a 24 or above. Negative affect was measured separately –
so a person could score high or low on measures of both positive attitude and
insecurity or helplessness.
During the follow-up period, 30 of the high
positive affect patients died of any cause, compared to 50 people with a lower
positive attitude score. Some of that association appeared to be driven by
exercise habits, the researchers found.
People with high mood scores were more
likely than other participants to say they exercised at least once a week, and
exercisers were half as likely to die as non-exercisers.
There was not a clear
difference, however, in how often people were hospitalized for heart-related
conditions, based on their positivity. During the study period, about half of
all participants were hospitalized for a heart attack, heart failure or chest
pain, for example, according to findings published in Circulation:
Cardiovascular Quality and Outcomes.
The researchers said past studies also found
a link between having a positive outlook and better heart health, but it was
unclear what explained the association. "There is some evidence to suggest
that even among people who are already ill, who already have heart disease or
diabetes or related conditions, that those people who are happier also have
better outcomes," Julia Boehm from Chapman University in Orange,
California, who has studied psychological well-being and heart health, said.
Health behaviours such as exercise are one possible explanation for that link,
she told Reuters Health. Some researchers have also proposed another mechanism,
suggesting optimism may affect physiologic processes in the body that would
ultimately influence heart health, such as inflammation levels. Pedersen and
her colleagues noted that they did not have information on participants' type
or intensity of exercise.
The researcher also said the study can't say how
exercise and positive affect may be linked. "We do not know what comes
first (also known as the 'chicken and egg' problem) and thus cannot make any
conclusions about the direction of causality – is it exercise that increases
positive affect or positive affect that leads to more exercise with an effect
on mortality or both?"
Pedersen told Reuters Health in an email: "Irrespectively,
it cements what we already know – namely that exercise is good for the
heart." Boehm, who wasn't involved in the new research, said there isn't
enough evidence to tell people with heart disease to be happier or more
optimistic in order to improve their outcomes.
But she agreed with Pedersen
that there are data to support recommending exercise to those people for heart
health. "Hopefully you would have the added benefit of feeling more happy
(and) optimistic," she said.