Dr. Marlene Grenon, a vascular surgeon at the San Francisco VA Medical Center and an assistant professor of surgery at the University of California, San Francisco, led the analysis of data from 1,024 participants in the Heart and Soul Study, which tracked men and women with coronary artery disease for about seven years.
"We discovered that there was an association between depression and PAD at baseline, and also found that the patients who were depressed at the beginning of the study had a higher likelihood of developing PAD during follow-up at seven years," Grenon said in a statement.
The study, published in the Journal of the American Heart Association, found that some of the risk for PAD was partly explained by modifiable danger factors such as smoking and reduced physical activity.
"We still don't know which comes first," Grenon said. "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? Or might it be a vicious cycle, where one leads to the other?"
Further research is needed to tease out cause and effect, Grenon said.
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