Could screening for and treating depression and anxiety reduce the risk of heart disease? Given that research is increasingly indicating a relationship, if not a causal link, internists may want to more proactively consider the possibility with their patients, according to experts.
Data clearly show that having an acute cardiovascular problem like a heart attack or need for a defibrillator can cause huge emotional distress. However, studies looking at the association between depression and an increased risk of developing heart disease aren't as clear. The studies are either observational or show that while patients who get antidepressants are less depressed, their mortality outcomes are no different.
Part of the problem is that the studies are not truly randomized clinical trials, said Richard Josephson, MD, professor of medicine at Case Western Reserve University School of Medicine and director of cardiac intensive care and cardiovascular and pulmonary rehabilitation at University Hospitals, both in Cleveland. “You can't randomize people to be depressed or not or to have heart attack or not, so it's hard to see how randomized placebo trials can ever occur,” he said. “So for people who believe randomized clinical trial data is the only standard, then [a link between mental health concerns and heart disease] doesn't exist.”
Even without reaching that gold standard, however, he contended there is enough evidence showing that depression and anxiety are modifiable risk factors for heart disease to prompt primary care physicians to be proactive. They can do that by coming up with a differential diagnosis that can be treated with targeted mental health interventions, he said. Such interventions can help break the cycle of patients who are too depressed to comply with heart-healthy behavior such as quitting smoking, exercising, and lowering alcohol intake, he noted.
Even if the link—not everyone will call it a risk factor—hasn't been completely vetted, internists can't go wrong by looking for clues to effectively treat the whole patient, advised Nieca Goldberg, MD, ACP Member, a cardiologist and medical director of the Joan Tisch Center for Women's Health at NYU Langone Medical Center in New York.
“Physicians should use their clinical skills to assess whether a person has primary arrhythmia or if the hypertension is related to anxiety,” she said. “Our job as physicians is not only to treat the blood pressure but also to help the patient have a better quality of life.”
Looking at the connection
It makes sense that a heart attack could lead to depressive symptoms or exacerbate preexisting ones, Dr. Josephson said. There are enough data, albeit not from randomized controlled trials, to lead the American Heart Association to issue a recent scientific statement that depression should be considered a risk factor for heart disease.
The relationship is independent of other stresses and occurs more in smokers, older people, single versus married people, and those of low socioeconomic status, he said.
Severe depression after a heart attack is related to a preexisting diagnosis of depression prior to the index event. “Someone hospitalized for depression 10 years ago who now has a heart attack is at extremely high risk of major depression thereafter,” he said.
But the conversation is murkier when looking at whether depression or anxiety leads to cardiovascular risk.
Studies, including a recent one by Goldie and colleagues presented last October at a meeting of the Canadian Cardiovascular Congress, show an association, not a causal relationship, between mental disorders and heart disease.
However, Dr. Josephson said, there are many studies showing that there is autonomic system dysfunction after MI, and this dysfunction correlates with an adverse prognosis. He was part of a study showing that the dysfunction correlated strongly with fitness, which strongly suggests that the mechanism of post-MI adverse prognosis may involve physical inactivity or lack of fitness.
He added that physical activity, perhaps via a structured program such as cardiac rehabilitation, may fundamentally improve a patient's prognosis.
“What convinces me is that the mechanistic studies in recent years are in an area where you can't do the most desired randomized trial,” he said.
Dr. Goldberg said physical evidence seen in studies includes that depressed patients' platelets are more likely to clot prior to therapy and that an association exists between increased anxiety and higher blood pressure.
“Physiologically we know stress and anxiety raises blood pressure and heart rate, so patients are more likely to report palpitations,” she said.
Studies on post-traumatic stress disorder (PTSD) are also showing an association with heart disease, from decreased cardiac blood flow to increased risk of heart disease events, said Beth Cohen, MD, associate professor of medicine at the University of California San Francisco and staff physician at the San Francisco Veterans Affairs Medical Center. She is also principal investigator of the Mind Your Heart Study, which is looking at the biological, behavioral, and psychosocial factors that increase chronic disease risk in patients with PTSD.
However, she said the reasons behind the findings, whether they are because of poor health behaviors, a biologic factor, or something else, are still fuzzy, making it unclear if patients who get treatment are less likely to have future disorders.
“We need to determine the specific mechanisms so we can develop new targeted treatments to prevent cardiac events in patients with mental health disorders,” Dr. Cohen said.
Opening a door
Findings of association should be enough to spur internists to open the door to a conversation with patients, especially those with adherence issues, and to consider whether there is depression or anxiety, Dr. Cohen said.
Even the SADHART study, which found that patients treated with medications had improved moods although cardiovascular outcomes remained the same, should be considered encouraging, she said.
“If you improve mood that's a good thing, because it can increase compliance with medications and healthy lifestyle recommendations,” Dr. Cohen said.
Internists who typically use a screening tool such as the PHQ-9 to detect depression should recognize its limitations, Dr. Josephson said. While it is an excellent screening tool for use by internists, it is not considered the gold standard, which is a structured clinical interview for depression.
“The PHQ-9 is fine for clinical application, but some of the ‘noise’ in research data likely relates to the PHQ-9's imperfections,” he said.
It can help, though, by distinguishing between an adjustment disorder characterized by sadness and appetite disturbance and complete debilitation or major depressive disorder, said Barry J. Jacobs, PsyD, director of behavioral sciences for the Crozer-Keystone family medicine residency program in Springfield, Pa. An internist can monitor the former and treat or refer the latter.
“Some [physicians] say, ‘Of course the patient is depressed. They've had a heart attack.’ They label it as normal adjustment reaction, which misses the mark,” he said. “They don't take into account a pathological condition which could be treated.”
To differentiate for a depression diagnosis, look for someone with a minimum of 2 weeks of symptoms and for moderate to severe depression and symptoms most of the day nearly every day, said Mary F. Morrison, MD, FACP, professor of psychiatry and internal medicine at Temple University School of Medicine in Philadelphia. There are both psychological symptoms of depression and physical symptoms (such as changes in appetite and sleep and fatigue).
Look for patients who express a lack of enjoyment in previously enjoyable activities, especially for those whose depressive post-cardiac event symptoms do not get better with time, added Dr. Josephson.
Patient management tips
A proven beneficial intervention for patients struggling with depression and anxiety is exercise, whether the patient is at risk for or has had a cardiovascular event, said Dr. Josephson. It may be enough for those with milder depressive symptoms.
“There's no question that regular exercise after a heart attack or bypass surgery cuts down the risk of depression, and to lesser extent anxiety, among other good things,” he said. Cardiac rehab, he noted, is recommended and associated with better quality of life and lower mortality.
Exercise has its benefits for at-risk patients as well. “Depressed people tend to be couch potatoes, so being depressed and less active may be the mechanism of depression that affects cardiovascular health,” he said.
Because exercise changes the autonomic nervous system, it may not only treat the symptoms of depression but also improve cardiovascular outcomes, he explained.
“Antidepressants make you feel better but not improve mortality,” he said. “Exercise makes you feel better and may affect fundamental biology.”
But it's not a cure-all, he pointed out. “There's much reason to think exercise will diminish but not totally eliminate the risk of future cardiovascular disease,” he said.
In addition to exercise, Dr. Jacobs said a patient's mental wellness plan should include a 20-minute daily relaxation technique such as doing breathing exercises or practicing yoga or meditation.
“Cognitive behavioral therapy is based on the premise that what we subconsciously say to ourselves has an impact on how we view the world and how stressed we become,” he said. Negative thinking can make patients more unhappy and stressed out.
“So maintaining cautious optimism ... a sense of hopefulness that we have the capacity to improve or manage a condition matters a lot,” he said.
As part of that plan, physicians should address social isolation.
People who have had a serious medical event or are depressed tend to isolate themselves just at the time when they're most vulnerable and could benefit from social support, Dr. Jacobs said. That strategy can backfire.
“People with a lack of support are at higher risk for depression and further adverse medical events,” he said.
He recommended that patients reach out to family members, return to church, and get back in touch with friends.
Virtual connections can also help, he said, pointing to the American Heart Association's recently launched network to connect heart disease survivors and their caregivers with others.
While medications can be useful, some drugs intended for major depressive disorders can contribute to lethargy and weight gain, Dr. Josephson said, noting that most primary care physicians are more likely to prescribe selective serotonin reuptake inhibitors that are unlikely to have those side effects. Dr. Morrison cautioned against prescribing relatively new antipsychotics without carefully reviewing the risks and benefits. “Antipsychotics can be part of the problem,” she said. “Their adverse effects on lipids and weight are huge.”
If medications aren't working, find out how depression is affecting patients' lifestyles and whether they're physically or socially active. Then follow up to look for clinical changes and if necessary adjust the dosage or switch to a different medication, Dr. Josephson said.
When to refer
Doctors should start a conversation with their patients with a referral team in place, experts noted.
While some internists have more training, experience, and even the disposition to handle patients with depression and anxiety, it's important to know when to refer the patient to a professional. A red flag is if a trial of antidepressant therapy in a reasonable amount of time is not helping the patient or if the patient is being nonadherent, said Dr. Goldberg.
“If you feel like you're refilling benzodiazepines and other anxiety medications too many times, then your patient needs to see a mental health professional,” she said.
Tread carefully when discussing that step with your patients, Dr. Goldberg advised.
“People don't want to hear, ‘You need to see a psychiatrist.’ They want to know why, with the doctor's care, it's so hard for them to get better,” she said.
Explain that despite all the things you do to improve physical health, one outlier is that anxiety or even depression can contribute to poor adherence and less positive outcomes, she said.
Patients are often open to the idea, Dr. Cohen said. “Patients are often relieved when someone understands that physical and emotional pains are linked,” she said.
When one of her patients in her 50s who had had stents, bypass surgery, diabetes, hypertension, and hyperlipidemia didn't schedule follow-up visits and lab testing or exercise, Dr. Goldberg felt she needed to make a referral.
“I said, ‘I know you're a smart, responsible person and I can't believe you forget to do this. I want to work with you on compliance to medications, diet, and exercise and refer you to a psychologist,’” she said. It worked. The patient now shows up for regular visits and follows through with lab tests.
“She's doing well and thanks me all the time,” Dr. Goldberg said.
Given the debate over the scientific evidence, or lack thereof, future studies should look more closely at the connection between heart conditions and depression and anxiety, said Dr. Morrison. She said specific attention should be paid to the changes in the autonomic nervous system that occur with depression, as well as the impact of mindfulness or biofeedback on mortality.
Even with those unanswered questions, she said it pays to treat the depression.
“We hope heart health improves from the point of view that people have more energy, feel better, and are more likely to take their medications,” she said.
With more focus in medical training and continuing medical education, internists are better equipped than ever to handle these complicated patients, Dr. Cohen said.
“There's a huge surge in mind/body health. I think culture is changing around that,” she said.
And the potential link between mental health and heart disease adds more heft to the connection.
“There are already lots of reasons to treat the depression,” Dr. Josephson said. “The link to cardiovascular disease is another.”