Columbia University (located in New York City) medical researchers designed a 10 year study to determine whether a lower risk for heart disease (coronary artery disease) is associated with positive emotions.   Over 1700 adult participants (862 men and 877 women) in the 1995 Nova Scotia Health Survey were evaluated at the beginning of the study for emotions ranging from joy, enthusiasm and contentment to depression, hostility and anxiety. Positive emotions are believed to predict cardiovascular health independent of negative emotions. 


Previous studies determined that patients with early-onset depression are at a much greater risk for developing heart disease (cardiovascular disease) after correcting for cardiovascular risk factors, and this effect occurs even in the absence of a diagnosis of major depression. People experiencing depression have a 1.5 to 2 times greater risk of developing heart disease, compared to otherwise physically healthy individuals.  


Heart disease patients, who’ve experienced a heart attack, stroke, abnormal and dangerous heart rhythms also, have a greater risk of developing depression. And after it develops, the depression leads to even more deterioration of the heart.


Also, depressed people who failed to respond to a trial of anti-depressant medications, after an acute coronary syndrome are at even greater cardiovascular risk.


During the course of this study, 145 heart disease events occurred.  After taking into account the participants’ age, heart disease risk factors, sex, and positive emotions, depressive symptoms predicted the incidents of heart disease.


The study found that the most anxious and depressed were at the highest risk of the disease. Positive emotions protected against the development of coronary heart disease while depressive symptoms increased the likelihood of disease onset. The researchers determined that positive emotions can easily be assessed, for example, as to whether or not the patient smiles during the clinical interview and if they appear to take pleasure or excitement in aspects of their daily life.


The researchers concluded that this large study, demonstrated increased positive emotions are protective against 10-year incidents of coronary heart disease and suggested that a key to preventive strategies may be increasing positive emotions and not merely reducing depressive symptoms.