By Amy Norton
NEW YORK (Reuters Health) - Heart attack patients with a stressful life may have a worse long-term outlook than their less-stressed counterparts, a new study finds.
Researchers found that of people hospitalized for a heart attack, those who'd felt stressed out recently were 42 percent more likely to die over the next two years.
It's not clear whether the stress is to blame, said lead researcher Dr. Suzanne V. Arnold, of St. Luke's Mid America Heart Institute in Kansas City, Missouri.
But she suggested that heart attack patients take some simple steps that could ease their stress and do their hearts good - like regularly going outside for a walk.
Many studies have looked into the link between chronic stress, like job strain, and the odds of developing heart problems. In general, they've suggested that highly stressed people face a greater risk.
But another question is whether chronic stress could affect people's prognosis after a heart attack.
In the new study, researchers followed 4,200 U.S. adults who'd suffered a heart attack. While they were still in the hospital, they answered questions about how much stress - such as job and marital stress - they'd felt in the past month.
Overall, people who reported the most stress were more likely to die over the next two years. Of more than 1,600 patients with moderate to high stress, 13 percent died.
That compared with just under nine percent of less-stressed patients, the researchers report in the Journal of the American College of Cardiology.
The numbers don't prove that stress dims a person's prognosis after a heart attack, Arnold said in an interview.
"It's really complicated to drill down," she said.
There are a lot of possible reasons that certain people find their lives stressful. They may be low-income, or suffer from depression, or have a generally negative disposition, for example. And all of those factors are tied to poorer heart health, too.
Arnold's team tried to control for as many factors as they could. They found, for example, that even among people without depression symptoms, high stress was linked to a greater risk of dying.
But it's still hard to "isolate" stress as the root cause of the higher death risk, Arnold said.
The findings are based on 4,204 heart attack patients at 24 U.S. hospitals. They all answered four questions on perceived stress - asking, for example, how often they felt "overwhelmed by difficulties piling up" and how often they felt able "to control important things."
People who scored in the top 40 percent were considered to have moderate to high stress levels.
The stressed patients were more likely to smoke, have depression symptoms, be obese or have high blood pressure or diabetes.
But even when the researchers factored those things in, chronic stress was linked to a 42 percent higher risk of death over the next two years.
"I think there probably is a real effect," Arnold said.
And that could mean direct or indirect effects, she noted. One direct way, in theory, could be through elevated levels of "stress hormones" like cortisol, which boost blood pressure and blood sugar.
Indirectly, stress could "absolutely" affect people's ability to manage their health, Arnold said. They may find it harder to exercise or stick with their medications, for example.
So should doctors start measuring heart attack patients' stress levels? Arnold said "it would be a stretch" to suggest that.
And so far, there's little evidence that therapies for tackling depression or chronic stress actually improve heart attack patients' long-term outlook - though they might get other benefits, like a better quality of life.
For now, Arnold suggested that heart attack survivors who feel stressed out try to take some simple measures. One would be to get regular, moderate exercise - particularly getting outside for a walk.
That's already generally recommended for your heart health, Arnold noted, and it might help lift your mood.
She said people could also try some type of stress management class, if they're interested. Whether that will affect your heart disease prognosis is unclear, though - and, of course, it costs money.
"Unfortunately," Arnold pointed out, "many of the people at risk (of high stress) are of low socioeconomic status. And they're least likely to be able to take a class."
SOURCE: http://bit.ly/T4rLG3 Journal of the American College of Cardiology, online October 3, 2012.