Blood test can tip off smokers.

• Position: Emphysema

During a regular annual physical exam, blood usually is drawn to check the health of a person's heart, kidneys, and liver. Now, researchers at New York-Presbyterian Hospital/Weill Cornell Medical Center say a blood test that detects the early signs of emphysema--well before symptoms occur--someday may be offered as well. Because most cases of emphysema are caused by smoking, the test being created can warn smokers about the impending development of the unbeatable disease--which is a major cause of disability and death in this country.

Not all smokers get emphysema, but those who find out they are at risk will be motivated to quit to halt progression of the disease, surmises the study's lead investigator, Ronald G. Crystal, chairman and professor of genetic medicine at Weill Cornell Medical College. "We know from other studies that smokers who learn from objective evidence that their health is in danger are much more likely to quit," he states. "That is the only thing that will help them avoid this deadly disorder."

Emphysema and chronic bronchitis are the twin disorders that make up chronic obstructive pulmonary disease (COPD), which is the fourth-leading cause of death in Americans. Given the aging population, COPD soon is expected to move up to third in mortality prevalence.

The new test measures particles that are shed by tiny blood vessels known as capillaries that surround air sacs (alveoli) in lungs. These particles are debris shed by ongoing injury...