COPD is a term that encompasses both chronic bronchitis and emphysema, two diseases that are characterized by airway obstruction that interferes with normal breathing. Airway inflammation can stem from exposure to harmful fumes in the air, chronic bacterial infections in the airways, and a genetic predisposition to an inflammatory response to these agents. In people with COPD, the airway inflammation may extend beyond the lungs and contribute to systemic symptoms and, ultimately, to an increased mortality risk. Markers of systemic inflammation have been identified, but the relationship between these markers and when and to what extent COPD develops has not been determined. This study will use data collected during the TESAOD and its 33-year follow-up to determine the relationship between COPD and the expression of various inflammatory proteins, including pro-inflammatory cytokines (e.g., IL-6, IL-8, TNF-alpha) and acute phase proteins (e.g., C-reactive protein, soluble CD14).