A landmark study, known as the Lung Health Study (LHS), has revealed some interesting findings about the early course and prognosis of chronic obstructive pulmonary disease (COPD). The LHS was an initiative of mine during the time that I was President of the American College of Chest Physicians (ACCP). Following two planning meetings sponsored by the ACCP, the National Heart, Lung, and Blood Institute (NHLBI) decided to go ahead with the study which should shed light on the early course of COPD. The Lung Division of the NHLBI funded ten centers in the North America. These centers enrolled 5,877 patients over the age ofÊ 35 but not yet 60, who had only mild degrees of airflow obstruction as judged by spirometry. The average age of patients enrolled was 48.5 and the degree of spirometric abnormalities was only slightly low. Patients were given either special intervention, which was an all-out attempt at smoking cessation, or ordinary care by their personal physician. Those patients who were successful in stopping smoking, i.e., nearly 40%, from the special intervention group had a far slower rate of loss of lung function compared with continued smokers. Those with the mildest abnormalities even had an improvement in lung function. ÊThe rate of lung function decline as judged by the simple flow test, i.e., forced expiratory volume in one second (FEV1), was the prime end point, being a strong indicator of outcome in COPD.
But there were some astonishing additional findings. The most common cause of death in the five year follow-up was LUNG CANCER! Fifty-seven patients, or 1% of the population died of lung cancer, whereas only 38 died ofÊ heart attack and stroke which have historically been considered the greatest risks from cigarette smoking. No patient died of COPD during the course of this study for the simple reason that the patients who were enrolled had only mild forms of disease
Thus, what the study tells us is that simple spirometric abnormalities are strong markers of premature death from lung cancer, heart attack, and stroke, and a few other disorders. Stopping smoking can greatly alter the outcome of all three major killers and COPD down the line. Accordingly, it is critical for all smokers to have measurements of their airflow in their physicians' offices using simple spirometry and to absolutely stop smoking at the first sign of any abnormality. This will help prevent premature morbidity and mortality from all of the diseases listed above.
Of course, it would be much better if the patients didn't smoke at all. But right now the tobacco industry continues to mislead the public about the addictive nature of cigarette smoking and continues to entice 3,000 teenagers to start smoking each day through advertising to begin this lethal habit which leads to addiction. The tobacco industry aims to replace those who die of smoking related disorders or wisely quit, with their unending appeal to young people.
I thought you'd be interested in these findings.
I'll be in touch next month.
Thomas Petty, MD