A slowly progressive airway disease that causes the gradual loss of lung function. COPD is an umbrella term that includes chronic bronchitis, chronic obstructive bronchitis, emphysema, and combinations of these diseases. The symptoms of COPD include chronic cough and sputum (a mixture of saliva and mucus) production and severe shortness of breath. As the disease progresses, people increasingly lose their ability to breathe. COPD is the fourth leading cause of death in the United States. The most common risk factor for COPD by far is cigarette smoking.
A number of studies have suggested that COPD is a risk factor for Type 2 diabetes. A study published in Diabetes Care in 2004 followed over 100,000 female nurses enrolled in the Nurses’ Health Study from 1988 to 1996. They were periodically surveyed about whether they had been diagnosed with emphysema, chronic bronchitis, asthma, or diabetes. Those with COPD were nearly twice as likely to develop Type 2 diabetes as those without COPD. (Women with asthma, however, were no more likely to develop diabetes than those who didn’t have asthma). Although the study was carried out in women, the researchers saw no reason not to believe the same association would apply to men.
The researchers suggested that inflammation and oxidative stress may explain this association: Increasingly, inflammation is thought to play a major role in causing Type 2 diabetes, and some of the same inflammatory markers that are increased in diabetes are increased in COPD. Both conditions have also been linked to a phenomenon called oxidative stress, in which highly energized compounds called reactive oxygen species, which react strongly with other molecules, damage tissue. In the case of COPD, oxidative stress injures the airway and promotes inflammation in the lungs, and oxidative stress has been implicated as an underlying cause of the insulin resistance seen in Type 2 diabetes.
COPD cannot be cured, so prevention is key. The most important step for preventing COPD—or stopping or slowing its progression—is avoiding smoking.