Studies suggest that about 50 percent of people who smoke will develop lung disease. This might explain why so many smokers develop COPD, and why COPD is now the third leading cause of death in the U.S. So what is it that so closely links COPD with smoking?
**Chemicals. ** There are over 5,000 chemicals in a cigarette, and these are inhaled with both first and second hand smoke. They sit on the moist lining of the respiratory tract. While the exact mechanism is yet unknown, long term (chronic), or repeated, exposure to these chemicals has an influence on a person's genetics.
Genetics. Genes cause the release of proteins, and each protein carries out some bodily function. So some genes and the proteins they make are responsible for the normal development and maintenance of lung tissue. Long-term exposure to chemicals in cigarette smoke may cause genetic mutations that result in proteins that destroy instead of build lung tissue. Since each person has a unique genetic makeup, the impact of genetics on COPD may vary from person to person.
Tissues. The proteins from gene mutations cause changes within the lungs. Some prevent the normal development and maintenance of lung tissue, resulting in emphysema. Others cause changes to the tissues lining airway walls, causing airways to be chronically thick and narrowed. Others cause an increase in goblet cells that cause an abnormal amount of mucus. Others cause the destruction of cilia (hairlike structures) lining the airways, making it so this excess mucus is difficult to cough up. Disease. These changes are permanent, meaning they are chronic (always there). While lung disease will naturally occur in most adults, cigarette smoking speeds up this process by as much as 50 percent, resulting in a diagnosis of lung disease by the ages of 45 or 55. Loss of lung tissue is called emphysema, making it so your lungs have less capacity to move air. Excessive secretions and chronically narrowed air passages is chronic bronchitis. Together these make up a disease called chronic obstructive pulmonary disease, or COPD. **Living Well. ** Smoking is proven to both cause COPD, and speed up the natural progression of the disease. While there is no way to reverse the disease process, quitting smoking is proven to slow its progression. This is why it is of utmost importance that you quit inhaling cigarette smoke, whether its from your own or someone else's cigarette.