Background: Chronic bronchitis is related to worse general health status, exacerbations and mortality among subjects with COPD. Also less longstanding cough and phlegm may be related to worse prognosis in COPD but this has rarely been evaluated in population-based studies.
Aim: To evaluate the relationship between productive cough, exacerbations and mortality among subjects with and without COPD.
Method: All subjects with COPD (n = 993) were identified together with sex- and age matched reference subjects without obstructive lung function impairment from four population-based cohorts in 2002-04. Baseline spirometry and structured interview including data on exacerbations last 12 months were used in this study (n = 1986) together with mortality data collected until February 2012.
Results: Productive cough was more common in COPD than non-COPD (42.8 vs. 23.5%, p < 0.001), more common in men than women, but associated to exacerbations in both sexes. COPD-subjects with productive cough had the highest risk for exacerbations in both sexes and they had a significantly increased risk for death (HR 1.48, 95% CI 1.13-1.94) also when adjusted for sex, age, BMI, smoking habits and heart disease.
Conclusion: Productive cough was common and increased the risk for exacerbations in both sexes, in both COPD and non-COPD. COPD-subjects with productive cough had the highest risk for exacerbations and a significantly higher risk for death also after adjustment for common risk factors.
Keywords: COPD; Epidemiology; Exacerbations; Mortality; Productive cough.
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