Down and Out: Depressed CAD Patients Twice as Likely to Die as Those Without Depression

Regardless of clinical presentation, patients who develop depression at any point after a diagnosis of CAD are twice as likely to die as those who are not depressed, a new study has found.

Researchers say the findings, which are scheduled to be presented at the upcoming American College of Cardiology (ACC) 2017 Scientific Session, serve as an important reminder for cardiologists to keep depression on their clinical radar.

“Cardiologists need to be aware of the importance of screening for depression each time they see a patient, and really pay attention to things they are saying,” lead author Heidi May, PhD (Intermountain Medical Center Heart Institute, Salt Lake City, UT), told TCTMD.

May’s study examined time to death after a CAD diagnosis in 24,137 patients with angiographically proven CAD (stenosis >70%). Over 9.7 years of follow-up, 15% of patients were diagnosed with depression. May said prior studies have estimated that the rate of depression in patients with coronary disease is about 10% to 30%, so the findings in this group of CAD patients are in line with the known incidence.

Patients diagnosed with depression were more likely to be younger, female, and diabetic and to have had a prior diagnosis of depression or a CAD diagnosis that did not include MI.

Of the approximately 40% of patients who died during follow up, more deaths occurred in the group with depression than without depression (50% vs 38%; P < 0.0001). After adjusting for age, gender, prior depression, and angiography indication at presentation, depression was the strongest predictor of death, with depressed patients having about a twofold greater risk than those with no depression.

To TCTMD, May said she was a bit surprised that there wasn’t more of a difference in risk between patients with different clinical presentations, but added that “it just shows the importance of screening [for depression] and treating everyone with coronary disease.”

As to why depressed patients may be more likely to die, she noted that physiological changes caused by depression, as well as behavioral issues stemming from being depressed—such as not adhering to medication and lifestyle-change recommendations—may be to blame.

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Farouc Jaffer, MD, PhD (Massachusetts General Hospital, Boston, MA), who was not involved in the study, noted that the observational nature of the study makes the findings more suggestive than definitive, but he added that the overall concept that outcomes are worse for those with depression and coronary disease has been substantiated in several studies.

“I think there are a number of variables that I would love to know more about, including how much revascularization occurred, how much residual disease patients had, angina status and treatment, and gradient of depression status and treatment for their depression,” he told TCTMD. “Without that information we really can’t say that the clinical presentation . . . is independent of how people fare with depression.”

But Jaffer said the findings are “provocative and worth further investigation,” with a focus on identifying CAD patients with depression and ensuring that they are optimally treated. Some of that treatment may be in the form of revascularization, he noted, which has been demonstrated to improve depression symptoms. Jaffer’s research in recent years has shown a positive feedback cycle of angina and depression. In a recent study, he and colleagues reported that treating patients with chronic total occlusions and depression resulted in a 72% decrease in the incidence of depression at 1 month.

“The bottom line is that every patient with CAD should ideally have some type of PHQ2 [Patient Health Questionnaire-2] or PHQ8 screening to make sure they’re not being missed, because sometimes patients are reticent in the office to express their feelings,” Jaffer said. “Recognizing those markers and treating patients with antidepressants and revascularization strategies is an advisable, strategic plan.”