A nationwide study finds a link between depression or a history of suicide attempts in people younger than 40, and a higher risk for dying from heart disease.
The effect was especially prominent in young women.
“This is the first study looking at depression as a risk factor for heart disease specifically in young people,” said senior author Viola Vaccarino, M.D., Ph.D., chair of epidemiology at Emory’s Rollins School of Public Health.
“We’re finding that depression is a remarkable risk factor for heart disease in young people. Among women, depression appears to be more important than traditional risk factors such as smoking, hypertension, obesity and diabetes which are not common in young women.”
In the study, researchers reviewed data from 7,641 people between the ages of 17 and 39 who participated in the National Health and Nutrition Examination Survey-III (NHANES-III), a nationwide survey. Investigators analyzed data between 1988 and 1994 with deaths tracked through 2006.
Women with depression or a history of attempted suicide had a three times higher risk of dying from cardiovascular disease and a 14 times higher risk of dying from ischemic heart disease (heart attack).
Men were found to have a 2.4 times higher risk for cardiovascular disease and 3.5 times higher risk for ischemic heart disease.
Although prior studies have discovered a link between depression and heart disease, the research generally studied older individuals who often have many co-occurring conditions that complicate findings.
Researchers say this is the first study to examine a history of suicide attempts, along with depression, as a marker for future mortality from cardiovascular disease.
Also, unlike most previous studies of depression and heart disease, the authors examined major depression, which was assessed with a clinical interview based on accepted diagnostic criteria — a method believed to be “a more robust risk indicator” than that used in earlier studies.
Use of antidepressants was not included as a risk factor because less than six percent of those with depression or a history of attempted suicide reported their use, and no cardiovascular-related deaths occurred in that subgroup.
In the study, researchers accounted for the possibility that depressed people may have more lifestyle-related risk factors such as smoking and poor diet. They found a significant link to heart disease risk coming from depression and suicide attempts, even after correcting statistically for unhealthy behaviors.
“Direct physiological effects of depression may play a greater role than lifestyle factors in this young population,” the authors write.
Experts believe depression may increase risk of heart disease through physiological mechanisms, such as lower heart rate variability and increased cortisol (a stress-related hormone) and inflammation.
“This is a group that normally should be low risk,” Vaccarino said. “Studying these individuals more intensively could be important for understanding how depression affects the heart.”
The results are published in the journal Archives of General Psychiatry.
Source: Emory University