TUESDAY, Nov. 29, 2005 (HealthDay News) -- Missed medications and elevated stress hormone levels may help explain the link between depression and poor outcomes in coronary heart disease patients, suggest two new studies.
"Patients with depression are more likely to suffer heart attacks and heart failure, and more likely to die of heart disease, and no one knows why. These results give us two intriguing clues: one behavioral, one biological," Dr. Mary Whooley, a staff physician
at the San Francisco VA Medical Center and the principal investigator of both studies, said in a prepared statement.
One study examined the association between depression and self-reported medication adherence in 940 patients with stable coronary heart disease. Of those patients, 204 had been diagnosed with depression.
The study found that 14 percent of the depressed patients reported they didn't take their medications as prescribed over a 30-day period, compared with 5 percent of the non-depressed patients.
That study appears in the Nov. 28 issue of the Archives of Internal Medicine.
The second study involving nearly 600 people with coronary heart disease focused on 24-hour levels of urinary norepinephrine, a stress hormone. A total of 106 participants also suffered from depression.
The study found that 9.4 percent of the depressed patients had norepinephrine levels above the normal range, compared with 3.3 percent of the non-depressed patients.
The more depressive symptoms a patient had, the higher their norepinephrine levels, according to the study, which appears in the November issue of the American Journal of Psychiatry.
Whooley said that neither study indicates a mechanism for poor coronary outcomes, but both suggest further areas of research.
More information
The U.S. National Heart, Lung, and Blood Institute has more about heart and vascular diseases.
