In the Original Article, Susceptibility to Exacerbation in Chronic Obstructive Pulmonary Disease, Hurst et al. examined the rate of exacerbations among patients with COPD over a period of 3 years. The strongest predictor of an exacerbation in a given year was the presence of an exacerbation in the previous year.
The natural history of chronic obstructive pulmonary disease (COPD) is punctuated by exacerbations — acute increases in the severity of symptoms.
• What is the effect of COPD exacerbations on patients?
Exacerbations appear to accelerate the decline in lung function that characterizes COPD, resulting in reduced physical activity, poorer quality of life, and an increased risk of death. Exacerbations are also responsible for a large proportion of the health care costs attributable to this prevalent condition.
• How is COPD severity associated with exacerbation frequency and severity?
As the severity increased, exacerbations were both more frequent and more severe. The severity of disease also affected hospitalization in year 1, with the proportion of patients who were hospitalized increasing with the severity of disease: moderate disease, 7%; severe disease, 18%; and very severe disease, 33%.
Morning Report Questions
Q: What was the best predictor of future exacerbations?
A: The best predictor of an exacerbation in the first year was a treated exacerbation in the year before study entry (odds ratio, 4.30; 95% confidence interval [CI], 3.58 to 5.17; P<0.001).
Q: What other factors were associated with exacerbations in this study?
A: Exacerbations were significantly associated with worsening lung function (according to post-bronchodilator FEV1), greater impairment in health status (quality of life), a history of gastroesophageal reflux, and an increased white-cell count.
Table 2. Univariate Associations with the Occurrence of Exacerbations during the First Year of Follow-up.