Individual risks of developing chronic bronchitis and respiratory symptoms in smokers

Abstract

Work about -Tobacco smoking (TS) as an individual risk factor for the development of CB and respiratory symptoms (cough, sputum, dyspnea) (RS), bronchial obstruction (BO). Material and methods. The study group included 119 people (63 smokers, and 56 never-smokers), who did not have respiratory diseases and were not exposed to occupational risk factors. To establish the status of smoking and identify RS, a questionnaire was developed and validated, a spirometric study was conducted to assess BO. To analyze the effect of TS on the development of CB, the obtained parameters were compared among smokers and nonsmokers using the analysis of variance and nonparametric method of comparing medians. The TS relative individual risk of developing CB, RS and BO was calculated using age stratification, which eliminates confounding factors associated with age. Dose-dependent effects on the development of CB were evaluated using stratification of patients by the intensity of smoking.

Results: Risks of developing CB age adjusted (RR=10.4), RS and BO (RR=8, 10), respectively. This risk is “dose-dependent”, it increased from 5.8 to 32.73 with increasing smoking intensity from 10 pack/year to more than 21; for RS development it increased from 7.8—15.7 to 32.4—62.7. In smokers, a statistically significant decreased in bronchial patency and a 2-fold increased in the annual frequency of colds were revealed.

Conclusion: TS is a strong risk factor for developing CB, respiratory symptoms (cough, sputum, dyspnoe) and respiratory syndrome (BO). With an intensity of tobacco smoking for more than 20 pack/years, the TS attributable risk of developing bronchial obstruction is very high, which can lead to the development of COPD.