New research shows that adults with asthma are more than 12 times as likely to develop chronic obstructive pulmonary disease (COPD) than adults without asthma.
“It is possible that factors such as smoking and repeated episodes of acute bronchitis may facilitate the evolution of asthma into COPD, but the process by which asthma and COPD become comorbid conditions is not clear,” says the article’s lead author Graciela E. Silva, MPH, University of Arizona, College of Medicine, Tucson.
University of Arizona researchers examined data from patients enrolled in the Tucson Epidemiologic Study of Airway Obstructive Disease between 1972 and 1973. Twelve periodic follow-up surveys and lung function tests over the next 20 years showed that the 192 patients with active asthma at the beginning of the study were 10 times more likely to acquire symptoms of chronic bronchitis, 17 times more likely to receive a diagnosis of emphysema, and 12.5 times more likely to develop COPD than patients without asthma. No association was found between inactive asthma and the lung conditions. Age and current smoking were significantly associated with an increased risk of acquiring COPD, emphysema, or chronic bronchitis.
“Although most people living with COPD have a history of smoking, the majority of smokers do not develop COPD later in life, suggesting that other factors, such as genetic, occupational, or environmental conditions, convey significant risks,” says Silva.
The investigators, whose work was published in the July issue of CHEST, the peer-reviewed journal of the American College of Chest Physicians, caution that more research is needed to understand risk factors for onset and progression of COPD.
Asthma, Allergy Screening Tool for Students Validated
As anxious parents send their children back to the classroom this fall, some may be wondering whether they should add asthma to their lists of concerns. Now, all they have to do is ask. Researchers have validated a simple questionnaire that screens students for asthma and respiratory allergies. In a multi-center study, which appeared in the July issue of the Annals of Allergy, Asthma & Immunology, children ages 7 to 13 answered nine questions at school about their breathing and allergy symptoms. The answers then were compared to the results of double-blinded clinical examinations of those students. The investigators found that the children’s answers were generally predictive of a diagnosis of asthma or allergies. A parallel questionnaire completed by the parents of the children also was predictive, but not quite as strongly. The new validated screening tool was developed as a result of a project initiated 4 years ago. The American College of Allergy, Asthma and Immunology provided grants of $100,000 each for pilot projects to develop an asthma and allergy screen that could be used in schools.
Biofeedback May Aid in Asthma Management
Heart rate variability biofeedback appears promising as an adjunctive treatment for asthma, according to researchers from the Association of Applied Psychophysiology and Biofeedback (AAPB); it also appears to maintain asthma condition with a reduced dose of inhaled steroids. In a study of 94 outpatient, paid adult volunteers pre-stabilized on controller medication, those receiving either heart rate variability biofeedback alone or in conjunction with a “full protocol” of and training in abdominal breathing through pursed lips were prescribed less medication compared with two control groups, with minimal differences between the two active treatments. They also experienced fewer asthma attacks, better lung function, and fewer asthma symptoms. The researchers, whose work was published in CHEST, the journal of the American College of Chest Physicians, say the use of biofeedback warrants further evaluation as a complementary treatment to medication.
Potential Inherited Lung Cancer Component Found
A research consortium has found a possible inherited component for lung cancer, a disease normally associated with external causes, such as cigarette smoking.
Studying 36 families with a history of lung cancer in at least two generations, the Genetic Epidemiology of Lung Cancer Consortium—consisting of 12 research institutions and universities, including the National Cancer Institute (NCI) and the National Human Genome Research Institute (NHGRI), both part of the National Institutes of Health (NIH)—identified a major lung cancer susceptibility region on a segment of chromosome 6. Markers on chromosomes 12, 14, and 20 also indicated possible linkage to lung cancer susceptibility, although the results were not as strong. Identifying the locus was a critical first step, but more work needs to be done, according to NCI’s Jonathon Wiest, PhD. The researchers’ next goal is to examine more closely this region of chromosome 6 with the aim of locating the exact gene or genes that cause lung cancer susceptibility.
The findings, which appear in the September edition of the American Journal of Human Genetics, also revealed that the more those not carrying the predicted familial lung cancer gene smoked, the greater their risk of cancer. In carriers, on the other hand, any amount of smoking increased lung cancer risk. This discovery suggests that smoking even a small amount can lead to cancer for individuals with inherited susceptibility.