Depression may be risk factor in PAD

Physicians can play a key role in preventing and treating peripheral artery disease (PAD) by encouraging patients who show symptoms of depression to seek care, according to the authors of a study that found depression was associated with a greater risk of PAD. Some of these risk factors can be managed through lifestyle changes or medications, they wrote.

Depression has been shown to be a risk factor for coronary artery disease (CAD), and recent studies have looked at depression’s association with an increased risk of death due to stroke.

Given that CAD and PAD share some risk factors, S. Marlene Grenon, MD, a vascular surgeon at San Francisco VA Medical Center, and colleagues reasoned that depression also might be associated with PAD. To explore that association, they analyzed data from the Heart and Soul Study, a prospective study of 1,024 patients with CAD who were enrolled between 2000 and 2002 and followed for an average of 7.2 years. The results were published online July 25 in the Journal of the American Heart Association.

Of those patients, 1,018 had follow-up information about PAD events. To assess depression, the researchers used the validated nine-item Patient Health Questionnaire, which measures symptoms of depression. Other data included a patient medical history, a fasting blood sample, clinical findings and results from a behavioral self-report survey. They adjusted for potential confounders, mediators and other variables in their analysis.

Grenon and colleagues found that 19 percent of the patients reported depressive symptoms at baseline. Prevalent PAD was recorded in 12 percent of patients with depressive symptoms and in 7 percent of patients without depressive symptoms. They attributed part of the association to modifiable risk factors such as smoking and lack of physical activity as well as comorbid conditions and inflammation.

“This information will be important for patients and providers as they try to prevent the development and progression of PAD,” they wrote. “These findings suggest that more aggressive treatment of these risk factors could reduce the excess risk of PAD associated with depression.”

The authors acknowledged that the pathway—whether PAD or depression came first—was unclear. “Is it that patients with PAD become depressed because their mobility is impaired, or that people who are depressed engage in unhealthy behaviors such as smoking and lack of exercise, and are thus more at risk of developing PAD?” Grenon said in a release. “Or might it be a vicious cycle, where one leads to the other?”

Their study relied in part on self-reported questionnaires, which could be inaccurate. The majority of participants were men from an urban setting, making generalizability to other patient populations limited.

Research on CAD suggests that treating depression can reduce the risk of CAD, Grenon and colleagues pointed out, arguing that the same strategy could be extended to PAD. They encouraged providers to be on the lookout for depression and to encourage patients with depressive symptoms to be treated. They added that their findings reinforce the need to screen for traditional PAD risk factors and, when appropriate, to address those risk factors through lifestyle changes or medications.

“[B]ecause elevations in traditional, modifiable cardiovascular risk factors partially explain the excess risk of PAD associated with depression, the identification of depression in PAD needs to be prioritized, and accompanying risk factors should be assessed and aggressively treated,” they concluded.

Women often have been underrepresented in clinical trials for PAD yet the burden of PAD is high in women. How, then, should physicians treat their female patients? Look for answers in the October issue of Cardiovascular Business. To sign up for a free subscription, click here.