Smokers Pneumonia Risk Three Times Greater

Writing in the monthly peer-reviewed journal of the American College of Chest Physicians, Carlos A. Gonzalez, Ph.D., of the Institute of Epidemiological and Clinical Research, Hospital of the Consorci Sanitari de Mataro, Barcelona, Spain, along with three associates, studied 112 men and 93 women who had contracted community-acquired pneumonia. Among the patients with pneumonia, almost 65 percent were current smokers of cigarettes. Among the control group of 475 persons who did not have pneumonia, slightly over 56 percent were current smokers.

"The number of cigarettes smoked per day and the life-time pack-years showed a positive dose-response relationship, with a significant trend," said Dr. Gonzalez. Smokers who smoked more than 38 pack-years of cigarettes had a risk of getting pneumonia of over 3.15 to 1. The risk of ex-smokers was similar to current smokers, about 2.14 to 1. After 5 years of no smoking, the risk of acquiring pneumonia was reduced."

According to the researchers, the physical and chemical properties of cigarette smoke causes oxidative stress in people and alterations in the responsiveness of inflammatory cells.

The authors estimate that approximately 1 out of every 3 cases in these adults could have been avoided if no one in the population had smoked.

The investigators' results showed no difference in risk associated with the use of filter cigarettes, cigarettes made with darker tobacco, or the individual's depth of inhaling.

The study was conducted in a mixed residential-industrial area of Barcelona containing 74,610 inhabitants over 14 years of age. The researchers selected this area because all physicians who had first contact with patients with symptoms of pneumonia agreed to collaborate on the study. The physicians in public and private health care facilities covered 95.2 percent of this population.

"We feel we had an advantage in that all community-acquired pneumonia cases occurring in the entire population of this defined area over a two-year period were included,." said Dr. Gonzalez. "Thus, we avoided selection bias which might have been associated with hospitalized patients or with other selected groups of patients with pneumonia."

In Spain, the estimated prevalence of smoking among men and women over age 15 was 48 percent for males and 25 percent for females. Dr. Gonzalez characterized Spain's smoking prevalence as "middle-high" among other developed nations.

Trained physicians and nurses elicited study data from participants in their homes. Self-reported factors included weight, height, alcohol consumption, living conditions, medical history, and medical treatments during the previous year. Information on smoking was collected in separate sections for consumption of cigarettes, cigars, and pipes.

CHEST is published by the American College of Chest Physicians (ACCP), which represents 15,000 members who provide clinical, respiratory, and cardiothoracic patient care in the U.S. and throughout the world.