NEW YORK (Reuters Health) - The prevalence of chronic obstructive pulmonary disorder (COPD) is higher and stages of disease are more advanced than has previously been reported, according to findings from the Burden of Obstructive Lung Disease initiative.
And contrary to common beliefs, smoking is not the only factor contributing to COPD prevalence, the investigators report in The Lancet.
The research group, led by Dr. A. Sonia Buist at Oregon Health and Science University in Portland, examined the prevalence of COPD and its risk factors in adults who were at least 40 years old and were living in 12 cities on 5 continents.
More than 9,000 subjects were interviewed, and test results were obtained from 8,775. Stage II COPD or higher in 10.1 percent overall, 11.8 percent for men and 8.5 percent for women. The prevalence increased with age, usually affecting fewer than 5 percent of individuals in their 40s — up to 47 percent of men 33 percent of women age 70 and older.
The prevalence also varied widely by location, Buist’s group notes. Six sites reported COPD rates of at least 10 percent for stage II to IV disease. The prevalence ranged from 5.9 percent in Hannover, Germany to 19.1 percent in Cape Town, South Africa.
The study revealed risk factors other than smoking. For instance Cape Town reported very high levels of previous tuberculosis and occupational exposures, as well as high smoking rates.
In a separate report, Buist and Dr. David M. Mannino, from the University of Kentucky in Lexington, point out that COPD is preventable and treatable, but not fully reversible.
They describe risk factors for COPD, which include smoking; occupational exposure to gases, dust, vapors, and fumes; exposure to outdoor and indoor air pollutants, caused by burning organic matter for cooking and heating; and genetic factors.
Aging, bacterial or viral infections, asthma, gender, inadequate nutrition and poor access to health care are also associated with the development of COPD, the reviewers add.
Passive smoking exposure addressed by Dr. K. K. Cheng, at the University of Birmingham, UK, and colleagues. Their research is based on data for nearly 15,400 individuals in China who never smoked.
Twenty-eight percent of the subjects exposed to high levels of passive smoke were 48 percent more likely to have COPD compared with unexposed individuals.
Cheng’s team estimates that among people now living in China, who are 50 years of age or older, there will be 1.9 million deaths from COPD caused by passive smoking.
Related may further observations and suggestions for COPD. In one, researchers state that COPD is “underdiagnosed, undertreated, and underfunded and neglected by the public, pharmaceutical industry and physicians alike when compared with other major killers, such as cardiovascular disease and stroke.”
The other editorialists point out that the problem has been exacerbated by studies that evaluate new drugs for COPD, excluding patients with other illnesses commonly associated with it, such as heart disease and diabetes.
One solution, suggest in another editorial, is to use a new umbrella term - “chronic systemic inflammatory syndrome” - that would include cardiovascular disease, high blood pressure and some cancers.
SOURCE: The Lancet, September 1, 2007.