Symptoms of depression have been tied to heart problems in past studies. Is it possible that one condition causes the other?
Researchers set out to answer this question in a recent study on heart disease, stroke and depression.
Using medical records and questionnaires on depressive symptoms, these researchers found that increased symptoms of depression led to a higher heart disease risk.
The researchers also found that strokes tended to coincide with an increase in depression symptoms. The authors of this study suggested that these findings indicate that strokes may cause depression.
Dr. Eric Brunner of the Department of Epidemiology and Public Health in the University College London led this study.
Heart disease and stroke are two of the most common causes of disability and poor health, according to Dr. Brunner and colleagues.
Previous studies have looked at the effects of depression and heart disease on each other. However, reviews of those studies often concluded that it is difficult to tell whether depression increases the risk of heart disease or whether heart disease may cause depression.
This study by Dr. Brunner and team attempted to see whether one condition caused the other, and if there was a relationship between severity of depressive symptoms and heart disease.
A total of 10,036 people, each between 35 and 55 years old, participated in the study.
The researchers measured the participants' depressive symptoms using a general health questionnaire and a depression scale.
These participants attended follow-ups every five years, then every 10 years, for a total follow up time of 24 years.
Using the follow-up visits and medical records, the researchers gathered information about the participants' heart health and any major heart-related events, like stroke or heart attack.
The researchers found that symptoms of depression were a risk factor for stroke events, but only in analyses based on the five-year follow-up cycles.
Additionally, participants who had experienced a stroke reported twice as many incidences of depressive symptoms than those who had not had a stroke.
The researchers also found that increased depressive symptoms were linked to an increased risk of heart disease, but not stroke. This finding suggests that severity of depression symptoms may correspond with increasing risk of heart disease events, according to the authors of the study.
Dr. Brunner and team concluded that depression symptoms seemed to be linked to an increased risk of major heart disease events, but more studies are needed to clarify the relationship between the two health problems.
“This study provides a useful piece of the puzzle in determining whether depression is a potential cause of, or the result of, cardiovascular disease," said Adam Skolnick, MD, assistant professor in the Department of Medicine, Leon H. Charney Division of Cardiology at NYU Langone Medical Center.
"The authors nicely demonstrate that the degree of depression is directly related to coronary artery disease in a dose response fashion. This is in contradistinction to stroke where depression is not a cause but rather a potential result," said Dr. Skolnick, who was not involved in this study.
"Too often physicians fail to appreciate the importance of optimal mental health in preventing cardiovascular disease. Depression should be considered among the other well discussed risk factors like smoking and hypertension. It is only through rigorous studies like this one, that assess mental health prior to the diagnosis of cardiovascular disease, that we can truly understand this important mind-body interaction,” Dr. Skolnick told dailyRx News.
This study was published in the European Journal of Preventive Cardiology on February 3.
The research was supported by the British Medical Research Council, the British Heart Foundation and other health organizations. The authors declared no conflicts of interest.