Chronic obstructive pulmonary disease (COPD) is a chronic inflammatory disease of the airways that leads to a “progressive decline in respiratory function”. Although the exact cause of COPD is still unknown, smoking has been recognized as the most direct and certain causative factor. According to statistics, 12.4% of men and 5.1% of women over the age of 40 suffer from COPD, and the prevalence is even higher among smokers. In addition, the prevalence rate is positively correlated with the number of cigarettes smoked and the duration of smoking. For example: a smoker with a smoking index of 45 pack-years (1 pack a day for 45 years) has a 1/4 chance of getting chronic obstructive pulmonary disease (COPD); if a smoker starts smoking at the age of less than 15 years old, there is a 1/6 chance of getting COPD in the future, and smoking has a greater impact on the development of COPD in women, and the chance of getting COPD if a girl starts smoking at the age of less than 15 years old is 1/4. Research has proved that: a smoker who smokes 20 cigarettes or more every day of cigarettes a day for 10 years is likely to develop COPD. About 90% of people with COPD have a history of smoking, and the first priority for people with COPD is to stop smoking. Doctor’s tip Chronic obstructive pulmonary disease belongs to the common diseases, multiple diseases, there is a certain degree of difficulty in the treatment, so it is very important to prevent the occurrence of the disease, the sooner you quit smoking, the lower the chances of disease, even if the disease, the development of the disease is not so fast. 35 years old to quit smoking, to the age of 80 years of age lung function is still good; 40 years old to quit smoking, to the age of 70 years of age lung function is still good; even if you are 60 years of age to quit smoking, it is better than not quitting smoking all the time. In addition to smoking, indoor pollution can not be ignored. For example, “second-hand smoke” in public places. The use of biofuels, wood smoke, and cellular coal in rural areas can also increase the incidence of chronic obstructive pulmonary disease (COPD).