[The prevalence and risk factors of bronchiectasis in residents aged 40 years old and above in seven cities in China]

Abstract

Objective: To investigate the prevalence and risk factors of bronchiectasis in urban city of China.

Methods: A cross-sectional survey was conducted in 17 urban areas in Beijing, Shanghai, Tianjin, Chongqing cities, and Guangdong, Liaoning, Shanxi provinces. In this study, urban population-based cluster samples were randomly selected from each city/province. In the selected city communities, all residents at least 40 years old were recruited, interviewed with questionnaires and tested with spirometry. Each participant was asked whether he/she was ever diagnosed as bronchiectasis by physician, whether had symptoms of respiratory diseases and possible risk factors, etc.

Result: Data of 10 811 participants was enrolled for analysis, with a response rate of 75.4% (10 811/14 337). The overall prevalence of physician-diagnosed bronchiectasis was 1.2% (135/10 811), with 1.5% (65/4382) in male and 1.1% (70/6429) in female, without statistical difference in gender (χ² = 3.289, P = 0.070). Prevalence of bronchiectasis increased with age (χ² = 31.029, P < 0.001). There were no statistical significances in crude prevalences of bronchiectasis among cities (χ² = 10.572, P = 0.103), while there was a significant difference among cities after adjustment with confounders (Wald value = 22.116, P = 0.001), by using logistic regression analysis. Logistic regression analysis showed, bronchiectasis was significantly associated with elder ( ≥ 70 years vs 40-49 years; OR = 4.11, 95% CI 2.29-7.36), the family history of respiratory diseases (having two subjects with respiratory diseases in family vs no suffered relatives; OR = 2.04, 95% CI 1.06-3.94), respiratory infection during childhood (suffering two kinds of respiratory diseases vs never; OR = 4.89, 95% CI 2.03-11.81), exposure to coal (OR = 2.30, 95% CI 1.17-4.52), chronic pharyngitis (OR = 3.96, 95% CI 1.38-11.40) and pulmonary tuberculosis (OR = 3.07, 95% CI 1.89-4.98), heart diseases (OR = 1.64, 95% CI 1.11-2.42) and lung cancer(OR = 18.61, 95% CI 7.67-45.18).

Conclusion: The prevalence of bronchiectasis in population aged 40 years old and above in urban area in China is high and associated with multiple factors such as age, family history of respiratory diseases, respiratory infection during childhood, exposure to coal, chronic pharyngitis, pulmonary tuberculosis, heart diseases, lung cancer and so on.