Patients with anxiety or depression have previously been shown to have longer hospital stays and a worse prognosis after a heart attack, researchers note in the European Journal of Preventive Cardiology.
But earlier research hasn’t given doctors a clear sense of whether patients with specific types of emotional distress might put patients at greater risk for serious complications or premature death.
For the current study, researchers assessed almost 58,000 patients for emotional distress two months after a heart attack, and again at 12 months after the event. Overall, 21% of the patients reported persistent psychological problems in both assessments.
Researchers followed a majority of patients for at least 4 years. Compared to those who didn’t report any emotional distress at all, people who felt depressed or anxious at both assessments were 46% more likely to die of cardiovascular causes during the follow-up period and 54% more likely to die from other causes.
“Temporary mood swings, if they are not too frequent or dramatic, are a normal part of life,” said senior study author Erik Olsson of Uppsala University in Sweden.
“Feeling a little depressed after a heart attack might even be a good thing if it makes you withdraw a bit and get some rest,” Olsson added. “Emotional states help us regulate our behaviours.”
About 15% of the patients in the study experienced some symptoms of emotional distress two months after the heart attack that they no longer reported after one year.
Their odds of dying during the study period were no different from people who didn’t have anxiety or depression at either assessment.
It’s possible that people who reported depression and anxiety at both assessments had a harder time following doctors’ orders for an ideal recovery, Olsson said.
“Chronic emotional distress makes it harder to adopt the lifestyle changes that improve prognosis after a heart attack,” Olsson said. “These include quitting smoking, being physically active, eating healthily, reducing stress and taking prescribed medications.”
About 11% of the patients initially reported no symptoms of emotional distress but did feel some degree of depression or anxiety after one year.
These people didn’t appear at increased risk for dying of cardiovascular causes during the study period compared with patients reporting no emotional distress, but did have a 46% greater risk of dying from other causes.
These people may have had distress that wasn’t directly related to their heart attack, Olsson said. Instead, they might have experienced depression or anxiety due to other risk factors for mood disorders like poverty, limited education or lack of a spouse or job.
The study wasn’t a controlled experiment designed to prove whether or how mood disorders might directly hasten death after a heart attack.
It’s also possible that some people in the study had undiagnosed depression or anxiety prior to the heart attack that influenced their survival odds, the study authors note.
Researchers also looked at depression and anxiety combined, making it impossible to identify any differences in how each of these conditions might independently impact survival after a heart attack.
It’s also unclear whether treating depression or anxiety could impact outcomes, said Dr Robert Carney of Washington University School of Medicine and Barnes-Jewish Hospital in St. Louis, Missouri, who wrote an accompanying editorial.
“We do not know for certain whether treating depression or anxiety improves survival, but there is some evidence that it probably does,” Carney said. “At the very least, being free of depression and anxiety improves quality of life.”