Doctors miss depression diagnosis in many heart patients
GAINESVILLE, Fla. — When it comes to heart disease, many patients are singing the blues — yet too few doctors recognize it, University of Florida researchers warn.
A growing number of studies link heart disease and depression, a powerful risk factor equivalent to smoking or high blood pressure that hikes the risk of heart attack or death two to three times above normal. Conversely, those who are depressed are more likely than their cheerful counterparts to develop heart disease.
“It’s very common, and physicians — both primary care physicians and cardiologists — should be proactively screening patients in their office for depression to at least attempt to identify it,” cautions UF cardiologist Dr. David S. Sheps, writing in a depression-themed supplement of Psychosomatic Medicine released today. “Many patients are coming to see their primary care doctor or cardiologist for other reasons. Most of them are not aware they are depressed, and these physicians are not trained to detect depression or to screen for it. Most often the diagnosis is missed.”
At the very least, many physicians need to be more attuned to the relationship between heart disease and depression, Sheps said, adding that as many as a third of heart disease patients are depressed. But doctors now also suspect the drugs used to treat high blood pressure may worsen depression or even trigger a mood disorder in some patients.
The drugs used to treat hypertension may be equally effective at lowering blood pressure. Yet some may intensify feelings of depression as much as other risk factors, such as stroke or prior history of depression, according to findings from a large international study published today in the main issue of Psychosomatic Medicine.
“If a person is already depressed, a physician might want to consider a choice of one drug or the other for that patient if they are clinically equivalent — if the cardiovascular results and the blood pressure effects are the same,” said L. Douglas Ried, a professor of pharmacy health care administration at UF’s College of Pharmacy and a research health scientist in the Rehabilitation Outcomes Research Center at the Malcom Randall Veterans Affairs Medical Center.
The new findings stem from a substudy of the International Verapamil SR-Trandolapril study, or INVEST, funded by Abbott Laboratories. The UF-led trial tracked 2,317 of the more than 22,500 patients who were randomly assigned to one of two blood pressure-lowering treatment strategies: a sustained-release form of the calcium antagonist verapamil or the beta-blocker atenolol and diuretics. Both groups also could receive an angiotensin-converting enzyme, or ACE, inhibitor.
Nearly half the patients in the substudy, known as the Study of Antihypertensive Drugs and Depressive Symptoms, or SADD-Sx, were women; most were older than 65 and were white. Researchers compared self-reported symptoms of depression after one year of treatment and also sought to determine factors that would predict depressive symptoms. Study participants completed a standardized questionnaire known as the Center for Epidemiologic Studies-Depression, or CES-D, scale.
On average, after one year of treatment the mood of patients on verapamil SR improved. Overall mood did not improve among patients whose treatment included atenolol. Seventeen percent of patients taking verapamil SR reported being highly depressed, compared with 22 percent of those taking atenolol.
“The caveat is it’s not a formal diagnosis of depression,” Ried said. “The only thing we can respond to is how patients report their symptoms in our study. Nonetheless, even controlling for prior history of depression and for heart disease, a year later patients on atenolol still describe more depressive symptoms compared with patients on verapamil.”
Past studies, which have had conflicting results, led some practitioners to recommend beta-blockers not be used to treat hypertension among older patients because of possible depression-related side effects. Other research has linked calcium antagonists to increased risk of suicide among patients prone to depression. The advantage of the SADD-Sx study, Ried said, was the number of patients enrolled in the randomized, controlled trial — a larger number than any previous study — and its design, a head-to-head comparison of both treatment strategies. Researchers also accounted for biases that plagued past studies.
Still, future research should involve a more rigorous measure of depression, Ried said, adding, “It may be that these patients say they feel poorer, which is important, but whether there end up being differences in the number of patients being diagnosed with a major depressive disorder, that’s a different issue. It’s a clinically important issue. It has public policy considerations. It has patient care-related issues associated with it. So people who make the decisions about prescribing have to weigh that.”
Sheps, associate chief of cardiovascular medicine at UF’s College of Medicine and the VAMC, and the editor of Psychosomatic Medicine, said the SADD-Sx findings were intriguing, though in standard clinical practice most physicians generally haven’t noted an association between the drugs and the chance of depression. Still, doctors don’t tend to carefully gauge whether patients on certain drugs are more or less likely to be depressed, so the phenomenon may be more widespread than most realize, he said.
Women in particular face a two-fold problem: A diagnosis of heart disease may be overlooked if practitioners fail to link the atypical symptoms some develop with an underlying heart condition, and depression is twice as common in women as in men.
“Many physicians tend to treat women differently than men,” Sheps said. “This can lead to delayed recognition of heart disease. It’s also known that depressed people tend to express more symptoms and different kinds of symptoms than people who are not depressed. That could also influence the way doctors handle the symptoms. Chest pain that doesn’t seem to respond to treatment may be related to the fact that (patients) may have depression. Not all pain that patients complain of is directly related to a treatable aspect of heart disease; it may be related to a behavior situation that affects the perception of pain in general.”
Practitioners could easily check for depression using standardized questionnaires, he said. Whether adequately treating depression actually prevents heart disease-related poor outcomes is not yet known, Sheps said, but screening for depression is worthwhile, even if it turns out that treatment of depression doesn’t reverse the adverse prognosis for heart disease.
When depression is diagnosed, it is often treated less vigorously than it should be, said Ken Freedland, a professor of psychiatry at Washington University School of Medicine. Many patients who receive a prescription for an antidepressant never return to the pharmacy for a refill, even if they are still depressed. Also, many patients could benefit from well-tested, non-drug treatments for depression such as cognitive behavior therapy, yet these types of treatments often are not offered to them.
“Further research is needed to develop a more complete understanding of how depression increases the risk of death in patients with heart disease,” he added. “We also need more clinical trials to improve our ability to treat depression in patients with heart disease. We already know that depression can be treated, but we need treatments that are even more effective than the ones that are currently available.”