Leg Pain Due to Peripheral Artery Disease (PAD) May Curb Physical Activity, Increasing Risk for Depression

It can be a downward spiral. For people living with peripheral artery disease (PAD), leg pain is among the most common symptoms. When that pain interferes with how much these individuals walk, the likelihood that they will experience depression symptoms rises. So concludes a study recently published in Circulation: Cardiovascular Quality and Outcomes.

The finding was a partial “surprise,” said Kim G. Smolderen, PhD, MSc, associate professor of medicine (cardiovascular) and of psychiatry at Yale School of Medicine, and senior author of the study. She had suspected that it was mainly symptoms of depression that led to less walking, because from prior work, they knew that depression can decrease the desire of a person to exercise. However, the research found this was only partially true, and mostly the other way around.

Even though there are other factors that can contribute to the development of the condition, “It is because they went down on their physical activity that they became significantly more at risk of depression,” Smolderen said.

In their study, Smolderen and colleagues found that a person who lives with symptomatic PAD might also feel more stress and depression after receiving the diagnosis. In addition, health questionnaires that patients filled out, even before a formal diagnosis, suggested that early symptoms of stress and depression were present.

If the combination of PAD, depression, and episodes of high stress persists over time, it can increase the risk of death according to Smolderen, who also is co-director of the Vascular Medicine OutcomeS (VAMOS) research program and co-founder of the integrated cardiovascular behavioral health program at Yale New Haven Health.

“If your body is in a constant state of stress and fight-or-flight mode,” she said, “your systems are going to get depleted and it also affects your cardiovascular system, [including] your autonomic tone,” which is the balance between the sympathetic and parasympathetic nervous systems. If it is out of balance over time, it can increase the risk of cardiovascular death.

The study also found that experiencing symptoms of depression can increase the chances of hospital readmission and generally poor health in people with PAD.

Smolderen said that depression also affects a person’s sleep, and “if you are more stressed or depressed, you could also have a harder time in following recommendations for changing” your lifestyle by exercising, losing weight, and discontinuing smoking—all of which help control PAD symptoms.

Even though it might be hard to break the cycle, people with PAD can take simple steps to combat episodes of high stress and depression.

Supervised exercise or walking programs at home are the first line treatment for people with PAD. “And we know that these work better if there are cognitive behavioral therapy (CBT) approaches embedded within those programs, as well as motivational interviewing,” she added. “So, if we can deliver these physical activity programs with those behavioral components, chances of success are higher.”

CBT consists of a collaboration between the psychologist and the client on switching to more helpful thinking and behavior patterns so a person can reach their goals. On the other hand, motivational interviewing is a counseling method used to motivate people to make behavioral change, meeting them where they are in their process.

Not only could this type of training help people prevent high stress and depression, but it could also assist them in “walking through” the pain rather than stopping exercise. By maintaining a beneficial activity level, people with PAD can improve both their leg function and their overall cardiovascular fitness. This, in turn, may allow their bodies to form new pathways around the blood vessel blockages caused by PAD to deliver blood to the muscle tissue in the legs.

In some scenarios, Smolderen said, people might also be helped by angioplasty, a procedure where the blockages that cause them to experience pain, limiting walking abilities, are removed. Afterwards, a stent would be placed in the affected area in the artery to prevent new cholesterol build up.

The individual with PAD and their treating physician would discuss this treatment option only after trying other approaches, such as exercise, a healthy diet, and medication. The conversation would also consider the patient's preferences as well as indications for saving the limb in more advanced stages of PAD.

This scientific paper helps clarify the relationship between PAD and depression. “I think this was the first time where we were able to map out the directionality of what happens first,” Smolderen said.

“This is an important insight and has clinical implications for how and when we would screen for depression potentially, but also to prevent depression from happening in the first place in this population.”

According to Smolderen, the study “further confirms that we cannot look at vascular treatment needs separately from behavioral health needs” if patients are expected to make lifestyle changes. While integrating behavioral health with cardiovascular medicine has been studied, there is no current standard of care that combines them, she said. Smolderen is working on building such a program with her colleagues in cardiology and psychiatry at Yale.

She also hopes the team’s findings—and the VAMOS program that she co-leads with Carlos Mena-Hurtado, MD, interventional cardiologist and associate professor of medicine (cardiology) at Yale School of Medicine— might motivate people to invest in integrative programs and do advocacy work with organizations, such as the American Heart Association (AHA) or American College of Cardiology, to reform how the health system cares for this population.