Study shows depressed heart disease patients fail to take prescribed life-saving medication

Columbia University Medical Center study shows link between depression and worsening heart disease

Depression is known to be “hard on the heart” – now researchers are a step closer to understanding why. A new Columbia University Medical Center study examining potential links between depression and heart disease found that heart disease patients who showed symptoms of depression were substantially less adherent to taking a prescribed medicine than patients without depression. Patients who continued to show signs of depression three months after a heart attack or angina only took prescribed medications 67 percent of the time, compared to almost 90 percent in non-depressed patients.

The research, which was presented for the first time at the 63rd American Psychosomatic Society Annual Meeting is part of the Coronary Psychosocial Patient Evaluation Study (COPES), a multi-site, multi-project consortium that is funded by the National Heart, Lung, and Blood Institute. According to Karina W. Davidson, Ph.D., assistant professor of medicine at Columbia University Medical Center and principal investigator of the study, it was known that depression in heart disease patients increases the risk of death after a heart attack, but the explanation for the link had remained unclear until now.

“Taking your medication as prescribed is crucial for improving your chances of good recovery after a heart attack but many doctors struggle with getting patients to take their medication on schedule,” said Dr. Davidson. “Our study was designed to test if depression may be a significant factor in reducing adherence, thus potentially explaining why depression carries such a negative prognosis for the heart disease patients.”

The study showed that patients who were not depressed in hospital were highly adherent – they took the correct dosage of aspirin on 88% of all monitored days. The researchers then divided the depressed patients into 2 subgroups: those who remained depressed 3 months after the ACS, and those whose depressive symptoms had remitted by then. Only patients with persistent levels of depression significantly differed in their level of adherence from non-depressed patients: they took the correct dosage only 2/3 or 67% of the time, as compared to 86% in patients whose depressive symptoms spontaneously remitted after 3 months.

“This is a huge difference that could have an impact on patient survival”, concludes Dr. Davidson. “Moreover, it is of great significance to cardiologists and their patients, since medication adherence is a relatively simple, potentially modifiable behavior.”

The study objectively measured adherence to aspirin, a standard medication in heart disease patients, by using an electronic Medication Event Monitoring System (MEMS) – an electronic device stored in the cap of a pill bottle that records the date and time whenever the cap is opened. The study included 53 patients from the coronary care and cardiac care step-down units of three university hospitals who had survived an Acute Coronary Syndrome (ACS), which includes either a heart attack or documented unstable angina.

Dr. Davidson’s research will continue to examine the link between depression and heart disease by examining whether effectively treating depression in these patients will result in better medication adherence and subsequently a decrease in mortality.