Chronic obstructive pulmonary disease (COPD) is currently the fourth leading cause of death in the United States, behind heart disease, cancer, and stroke. It is expected to move into third place by 2020, and is increasing faster in women than in men. Cigarette smoking is believed to be the primary cause, and patients who stop smoking have a much better prognosis than those who continue. However, inflammation is also an important factor. Several authors now refer to COPD as a systemic inflammatory disease, which affects more than just the lungs. Skeletal muscle myopathy (weakness or degeneration), cardiovascular disease, diabetes, osteoporosis, anemia, and depression are associated with COPD and attributed to “overspill” of inflammatory molecules.
Inflammatory markers rise in the lungs first, then in the circulatory system, according to Reference 3. Thus sputum tests may be better than blood tests for diagnostic purposes.
Lung function declines with age even in healthy adults, and COPD accelerates the rate of decline. The first line of defense against COPD is to stop smoking. Beyond that, drugs including corticosteroids and bronchodilators may be of some benefit. Reference 1 reported that anti-inflammatory drugs have a modest effect in slowing the decline of lung function. An intriguing possibility on the horizon is the use of statin drugs as anti-inflammatories. These drugs are commonly used to lower cholesterol. Many patients with COPD also have high cholesterol, and observational studies have suggested possible benefits of statins for reducing exacerbations of COPD. Other anti-inflammatory drugs, including tumor necrosis factor alpha blockers, are also under investigation.
I found 137 current clinical trials of anti-inflammatory treatments for COPD. In addition to steroid drugs, proposed treatments include caffeine, dietary fruits and vegetables, mud bath therapy, and mannitol (a naturally occurring polymeric sugar similar to sorbitol).
The authors of Reference 1 recommended emphasis on patient education and patient-physician partnership for COPD treatment. Patient guides are available online at www.goldcopd.org and www.internationalcopd.org.