Indiana University Purdue University Indianapolis

Health Study Reinforces What Poets and Songwriters Have Long Known

Release Date: 
Aug 1 2012

Jesse Stewart, School of Science at IUPUIA new study reinforces what poets and songwriters have long known: events like ending a romantic relationship, if they lead to depression, can break your heart.

Using data from a large scale, long-term study, the Coronary Artery Risk Development in Young Adults (CARDIA) Study, Jesse C. Stewart, Ph.D., an associate professor in the Department of Psychology at Indiana University-Purdue University Indianapolis, and his co-authors searched for two things:

• Which symptoms of depression increase the risk for heart disease?
• Mechanistically, how do these symptoms impact heart health?

Their findings are reported in a paper, entitled “Depressive Symptom Clusters and 5-Year Incidence of Coronary Artery Calcification: The CARDIA Study,” that was printed in the July 24th issue of the #1 cardiology journal Circulation, published by the American Heart Association. The paper can be found at: http://circ.ahajournals.org/content/126/4/410.abstract.

Depression has long been thought to be a risk factor for heart disease, like high blood pressure or high cholesterol, Stewart said. “Thirty years of research has shown that someone who is depressed today is more likely to have a heart attack in the future than someone who is not depressed,” Stewart said.

But efforts by health care providers to help reduce the risk of heart disease among those suffering from depression have not been successful, compared to efforts such as those that help people with high blood pressure improve their heart health, Stewart said. One issue is health care providers haven’t known which of the symptoms of depression, grouped into four clusters, to target to reduce heart disease risk.

The four clusters of depression symptoms are: emotional symptoms, such as depressed mood and lack of pleasure or interest in life; cognitive symptoms, such as difficulty concentrating; behavioral symptoms, such as slowing of movement or speech; and somatic symptoms, like fatigue and sleep disturbance.

The question was which cluster is the most cardiotoxic, Stewart said.

Stewart said this new study set out to identify the cardiotoxic culprit, in terms of which cluster best predicts the development of calcium deposits in the arteries of the heart, a condition that substantially increases the risk of a future heart attack.

Examination of the data on 2,171 middle-aged adults (58 percent female, 43 percent African American) from the CARDIA Study showed that the emotional symptoms cluster was more cardiotoxic than the other clusters, Stewart said.

“In a large and racially diverse sample of middle-aged community members, we observed that the relationship between elevated depressive symptoms and incident coronary artery calcification was driven largely by the emotional symptoms cluster,” Stewart said. “The observed relationship was independent of age, sex, race, education, and antidepressant use and was similar in magnitude across gender and racial groups.”

The findings are contrary to a trend in research literature suggesting that the somatic symptoms may be the most cardiotoxic, Stewart said.

Stewart said that stressful life events, such as divorce and job loss, can sometimes lead to a major depressive episode – where an individual feels down and depressed and/or loses interest or pleasure in almost all activities most of the day, nearly every day, for at least two weeks.

The examination of the data yielded some information, but not a complete picture about how emotional symptoms translate to physical problems that affect heart health, Stewart said. Additional studies are needed to identify all of the processes at work.

It was clear, however, that increased smoking partially explains the elevated heart disease risk of individuals experiencing the emotional symptoms of depression, Stewart said. Smoking is a well-established cardiovascular risk factor.

The results of the study suggests that a health care provider who is concerned about the heart disease risk of a depressed patient should make sure the treatment the patient receives is effective at reducing the emotional symptoms, Stewart said. If the depressed patient is a smoker, the provider should also take steps to help the patient stop smoking.

Co-authors of the paper are: Desiree J. Zielke (IUPUI), Misty A.W. Hawkins (IUPUI), David R. Williams (Harvard University), Mercedes R. Carnethon (Northwestern University School of Medicine), Sarah S. Knox (West Virginia University School of Medicine), and Karen A. Matthews (University of Pittsburgh School of Medicine). The CARDIA Study is funded by the National Heart, Lung, and Blood Institute of the National Institutes of Health.

The School of Science at IUPUI is committed to excellence in teaching, research and service in the biological, physical, behavioral and mathematical sciences. The school is dedicated to being a leading resource for interdisciplinary research and science education in support of Indiana's effort to expand and diversify its economy.