Association Between Amount Of Smoking With Chronic Cough And Sputum Production

Background: Smoking is a major cause of respiratory disease. We evaluated the association between the amount of chronic smoking with chronic cough and sputum production as a surrogate of pulmonary abnormalities Methods: 139 patients who underwent left ventricular ejection fraction measurement for clinical reasons, were evaluated for the presence of chronic cough and sputum production with reference to the length and amount of smoking. Results: The length and amount of smoking increased the risk of sputum production (smoking less than 10 pack years (9 of 48 18.8% vs smoking more than 10 pack years 38 of 108, 35.2%, OR: 1.3 CI 1.03-1.5, p=0.03). The length of smoking over 50 pack years vs less than 5 pack years was also significantly associated with chronic cough (24 of 31, 77.4% vs 22 of 52, 42.3%, OR: 4.7 CI: 1.7-12.7, p =0.002). Furthermore the mean length of smoking was significantly longer in patients with chronic cough (34.9  38.2 vs 49.1  40.2, p=0.03) or increased sputum production (34.6 39 vs 56.0  40.4, p=0.002). Conclusion: Increasing in length and amount of smoking is associated with increase risk for chronic cough and sputum production consistent with dose dependent negative effect of chronic smoking.