Smoking cigarettes increases a person's risk for many health problems, including cancer, heart disease, and lung disease. Several studies have shown many benefits for smokers who quit. However, no studies have proven that smoking cessation programs lead to better long-term survival. Chronic obstructive pulmonary disease (COPD), a disease of the air sacs and air passages of the lungs, is one of the many health problems to which smoking contributes. People with COPD are short of breath and sometimes cough and wheeze. Damage to the lungs and symptoms slowly worsen over time, especially if people do not stop smoking. Smoking cessation is particularly important for people with COPD who want to slow the worsening of their disease.