Reported and unreported exacerbations of COPD: analysis by diary cards.

BACKGROUND: Exacerbations of COPD are a major cause of morbidity and mortality; however, it has been reported that nearly half of such episodes based on symptoms are classified as "unreported" (no change in treatment), although the reasons are unknown.
METHOD: We used a symptom-based diary card to study 155 symptom-defined episodes (74 episodes in which treatment was not changed) in 19 patients with alpha(1)-antitrypsin deficiency.
RESULTS: The average length for the untreated episodes (time to resolution of all symptoms) was shorter than treated episodes (mean +/- SE, 8.3 +/- 1.0 days vs 16.1 +/- 1.6 days; p < 0.001). Of most importance, the patients documented feeling less well than usual for an average of only 1.9 +/- 0.4 days for untreated episodes, vs 11.7 +/- 1.7 days for treated episodes (p < 0.001). We developed a scoring system based on the symptoms of breathlessness, well-being, sputum color, and volume to quantify the episodes. The scores were higher for the first day of the treated episodes than untreated episodes (33.5 +/- 0.6 vs 28.4 +/- 0.5, respectively; p < 0.001), and the treated episodes had total scores that exceeded the baseline more than the untreated episodes (160.5 +/- 20.0 vs 43.4 +/- 6.6; p < 0.001). Antibiotics or steroids were started 4.4 +/- 0.5 days and 4.9 +/- 1.8 days on average, respectively, after symptoms changed, suggesting that the early return of well-being to normal is central to the episodes described as unreported (untreated) by others.
CONCLUSION: The diary card analysis described here provides a tool to document therapies that influence health-care-dependent exacerbations of COPD.