Depression is one of the most common health disorders in the US, and heart disease is a leading cause of death. “Although they can and do occur separately, research shows that the two conditions are often connected,” health experts write in the February issue of the Mayo Clinic Women’s HealthSource.

Previous studies have shown that depression is more common among people with heart disease than among those without. Researchers found that one in three heart attack survivors experience depression, compared to about one in 20 adults in the general population.

Depression has also been shown to be a precursor to heart disease. In one study of postmenopausal women, investigators found that those with symptoms of depression were 50 percent more likely to develop or die from heart disease than those without such symptoms, even though they had no prior history of heart disease.

Explaining the connection between the two conditions, the Mayo Clinic experts note that depression affects not only the mind but also physical health. Depression has been linked to increased blood pressure and abnormal heart rhythms, as well as chronically elevated stress hormone levels, which can increase the heart’s workload.

“Even if you don’t have heart disease, if you are chronically depressed, you are at somewhat increased risk of heart disease,” Dr. Sharonne Hayes, a specialty reviewer of the HealthSource publication, told Reuters Health. What’s more, people with a history of depression “are susceptible for recurrence” if they develop heart disease, said Hayes, who is also the director of the Women’s Heart Clinic at the Mayo Clinic in Rochester, Minnesota.

Yet, “the complex interplay between the two conditions may allow for one or both to go undiagnosed,” according to the HealthSource article.

Findings from a previously reported study show that even doctors and nurses do not always readily assess depression in heart patients, and it is “hard for patients to recognize” their own depressive symptoms, Hayes said.

This “tells us we’re probably missing some people who need to be treated or at least further evaluated (for depression),” she said.

Symptoms of depression include persistent sadness, loss of interest in normal activities, feelings of guilt or hopelessness, tiredness, restlessness and changes in appetite. Some of these symptoms may “be discounted by many with heart disease or viewed as a natural part of dealing with aging or heart-health problems,” the report indicates.

According to Hayes, “It may be natural to grieve and be sad if you have a new diagnosis of heart disease.” If those feelings persist or interfere with normal daily functioning, however, heart patients should “specifically mention that and be evaluated (for depression),” she advised.

SOURCE: Mayo Clinic Women’s HealthSource, February 2006.