More heartache in lung disease

Study shows close link between pulmonary fibrosis and CAD

By SH Cyr

Perhaps the most depressing thing about heart disease is its tendency to come packaged with other deadly and debilitating conditions. More bad news along these lines comes from a new study from UCLA and the University of Pennsylvania. It suggests that patients with the progressive lung disease pulmonary fibrosis are running more than twice the normal risk of developing heart disease.

Published in the March 8 issue of the Archives of Internal Medicine, the study showed a particularly close link between pulmonary fibrosis and the most severe forms of heart disease � patients with pulmonary fibrosis were four times more likely to have multivessel disease than those without the lung condition.

The investigators reviewed coronary angiograms of 630 patients at the University of Pennsylvania, who were being evaluated for lung transplant.

"We were very surprised by the large number of pulmonary fibrosis patients who had also developed advanced coronary artery disease," said lead author Dr David Zisman of the Division of Pulmonary and Critical Care Medicine at the David Geffen School of Medicine at UCLA.

This is the first study of its kind, and researchers noted that pulmonary fibrosis and coronary artery disease (CAD) may prove very similar � both cause inflammation that leads to scarring and/or plaque development. The two conditions share many histopathological characteristics. "Visually the disease processes look very much the same," noted Dr Zisman.

According to Dr Zisman, this study adds to the growing body of research taking a closer look at the impact of the inflammation process throughout the body. "Inflammation plays a key role in so many diseases, from Alzheimer's disease and heart disease to cancers as well as pulmonary fibrosis," he said. "The more we learn about the interaction of such diseases, the better we will be able to direct treatments."

"In the next step of research, we will look more closely at the processes that underlie development of these two diseases," added Dr Robert Strieter, a study author and vice chair of medicine at the David Geffen School of Medicine at UCLA.

According to Dr Strieter, researchers will next try to establish if substances produced by a pulmonary fibrosis lung may be reaching the heart to generate or exacerbate heart disease. It may be that simple ischemia is the cause of the link.

The most common form of pulmonary fibrosis is idiopathic pulmonary fibrosis, which affects five million people worldwide and roughly 10,000 Canadians. Most patients are eventually referred for lung transplant.