Smoking rates in many Asian countries have increased dramatically in the past several decades. For example, it's estimated that more than two-thirds of Chinese men smoke. This bodes ill for the future of many of these smokers, and for the health care systems in these countries as smokers begin to develop lung ailments after many years of smoking.
Dr. Don Sin is a lung specialist at the University of British Columbia in Vancouver. He reviewed data collected recently by a group of public health researchers from Guangzhou, China. It is one of the largest studies done to date in China to gauge the extent of lung disease in smokers, involving some 20,000 people.
"What these investigators did was they selected various towns and cities across China," explains Sin. "And then they went in and randomly selected people over the age of 40 and invited them to this study. The study consisted of a short questionnaire that individuals had to fill out and a test called spirometry, or more commonly called lung function test. It's this simple breathing test, which tells you how much lung capacity you have."
The research team found about 8 percent of the adults had lung function tests consistent with a diagnosis for chronic obstructive pulmonary disease, or COPD.
COPD used to be called 'smoker's lung' and referred to several diseases now known separately as emphysema and chronic bronchitis. "Really they were referring to the same thing," Sin says. "In general, it means chronic lung disease related to inflammation that is not fully reversible with various medications like steroids, or bronchodilators."
Sin says what surprised the researchers was the finding that women also had high rates of COPD - about 5 percent — even though many fewer women smoke. He suggests that is related to the kind of work women do in the home.
"Some of that is probably attributed to the so-called biomass exposure," Sin says.
"Women do most of the cooking in many parts of China and they're exposed to fumes and dust related to cooking, you know, over an open fire or using [wood and coal] as their cooking fuel."
Sin says although 8 percent might seem to be a small number, it actually represents tens of millions of people in China who will become ill with severe respiratory disease in the near future. He predicts that lung disease will probably become the second or third most common cause of death in the country. He notes that few anti-smoking measures are being enacted to reverse the trend.
Sin wrote a commentary that accompanies the research article. They're both published in the most recent issue of the American Journal of Respiratory and Critical Care Medicine.