Thinking positive thoughts can do more than make you smile—it could also help your heart, according to new Duke research.  

The study—led by Alexander Fanaroff, a fellow in the department of cardiology at the Duke University Medical Center—found that a positive outlook may improve the outcome of people with chronic angina. This condition involves chest pain or pressure experienced when the heart doesn't receive enough oxygen, which sometimes occurs during physical activity. 

The findings will be presented at the American College of Cardiology's 67th Annual Scientific Session March 10. 

“What you find is that patients that have better expectations for recovering have better long-term outcomes,” Fanaroff said. 

The researchers, who were experts at Duke Clinical Research Institute and Columbia University, aimed to measure if people with heart-related chest pain who reported being optimistic about their future health would have fewer heart-related hospital stays and procedures than those who weren’t optimistic. 

Although much attention has been given to the link between depression and heart health, this is the first study to look at whether optimism could be protective for those with heart disease and chronic angina.

It found that those who characterized themselves as more optimistic were 40 percent less likely to be hospitalized with angina or to require surgery to restore blood flow. Even after accounting for the fact that the optimistic group was healthier overall, they were still 30 percent less likely to be hospitalized or have the procedure. 

The researchers used data from almost 2,400 people with chronic angina who were having a procedure to open a blocked artery. These patients filled out a questionnaire about their quality of life, the conditions of their angina and how optimistic they were about their future health. They answered the same questions after one, six and twelve months. 

Out of the patients given the questionnaire, 782 were most optimistic, 1000 were somewhat optimistic, 451 were undecided and 123 were not optimistic. These opinions remained stable over time. 

Those who said they were most optimistic reported less angina and were less likely to have a history of heart attack, heart failure, diabetes and chronic kidney disease. 

However, Fanaroff cautioned that the research was observational and has limitations related to correlation and causation. 

“We think about stuff like this as hypothesis generating as opposed to hypothesis confirming,” he said. 

He noted that there are three possibilities for the results the study found. People may be able to accurately predict what their disease progression will be like and have adequate expectations based on how they are feeling, so those who are in better health feel more optimistic.

Alternatively, people who are more optimistic might engage in behaviors that help them get better.

“If you don't think you’re going to get better, maybe you’ll continue to not exercise or smoke cigarettes,” Fanaroff said. 

Another possibility—especially in the case of chronic angina—is that optimistic people who have symptoms avoid panicking and rushing to the emergency room, instead calling their doctors for advice. This leads to fewer hospitalizations overall.  

Fanaroff explained that this research is important because it can lead to possible clinical trials and interventions to improve outcomes of those with chronic angina. 

Next up, he said he hopes to do a randomized control trial involving efforts to improve patients’ outlooks. 

Although a positive attitude may not actually be causing patients with heart conditions to get better, encouraging them to focus on good thoughts is still worthwhile. 

“As a physician, it doesn't really hurt anybody to help make somebody feel optimistic,” Fanaroff said.