International conference here focuses on Chlamydia and heart disease

One hundred scientists from around the world met last week in Seattle in the largest conference yet to focus on the possible connections between bacteria and heart disease.

The symposium focused on the relationship between Chlamydia pneumoniae and atherosclerotic cardiovascular disease. Dr. J. Thomas Grayston, professor of epidemiology at the UW School of Public Health and Community Medicine, discovered Chlamydia pneumoniae in the mid-’80s.

Scientists are currently exploring whether the Chlamydia bacterium that Grayston and others have found in diseased coronary artery tissue is a cause of heart disease, or the equivalent of an innocent bystander. If it’s a cause, doctors might someday be able to treat heart disease, the nation’s number one killer, with antibiotics.

Organizers have dedicated the gathering to Grayston, in recognition of his career devoted to understanding the biology of Chlamydia pneumoniae. Other strains of Chlamydia are involved in many illnesses, including sexually transmitted disease. Chlamydia pneumoniae is transmitted, instead, from respiratory system to respiratory system, much like the flu. The bacterium may later show up in tissues altered by atherosclerosis.

Grayston said symposium participants discussed further tests to determine if Chlamydia is a cause of coronary disease. “I don’t think there will be a single magic experiment that will prove it,” he says. “It will take a variety of work in laboratories and clinics.”

One clinical study that is under way — directed by Grayston — gives participants either an antibiotic or a placebo for a year. Participants will be followed for three years to monitor for coronary events such as heart pain or heart attacks. Researchers at 26 sites, including the UW, are enrolling subjects for this study.

At the symposium, topics included the epidemiological association of Chlamydia pneumoniae and atherosclerosis; detection of C. pneumoniae in cells; models of C. pneumoniae in different animals; and the potential for a C. pneumoniae vaccine.

The symposium was hosted by the UW School of Public Health and Community Medicine, with sponsorship by the Infectious Diseases Society of America, and co-sponsorship by the Centers for Disease Control and Prevention, the National Institute of Allergy and Infectious Diseases and the National Heart, Lung, & Blood Institute. ¶ Walter Neary