Prevalence and risk factors of chronic obstructive pulmonary diseases in a Hlai community in Hainan Island of China

Objectives: We investigated prevalence and risk factors of chronic obstructive pulmonary disease (COPD) in a population of Hlai (the Li) ethnicity, a major minority, in Qicha Town, Changjiang County, Hainan Province, PRC, during 2014. Methods: All residents at the age of 40 years or older were interviewed with standardized questionnaires. Spirometry was performed to measure the possible airflow limitation. According to the GOLD criteria, post bronchodilator FEV1/FVC < 70% was defined as COPD. Case-control study was used to screen the risk factors by analyzing COPD group (212 cases) and non-COPD control group (236 cases). Single factor analysis and multiple factor logistic regression analysis were used as statistical methods. Results: The prevalence of COPD in the residents at the age of 40 years or older of Hlai community was 5.07% (286/5637) (95% CI=0.045-0.057). In the logistic regression analysis, the COPD prevalence was 5.07% (147/2901) in men and 5.08% (139/2736) in women, respectively, with odds ratio (OR) 1.003, 95% CI 0.790-1.272 and P > 0.05, suggesting that the sex did not affect the COPD prevalence in the investigated samples, but age (OR = 1.096), expectoration (OR = 87.917), locomotor activity limitation (OR = 3.908) and frequency of respiration (OR = 2.512) were risk factors and associated with the development of COPD. Notably, although the tobacco smoker in male and female COPD patients were 48.6% (54/111) and 4.0% (4/101), respectively, passive smokers in female with COPD were 45.6% (46/101). Conclusion: In the Hlai population aged >= 40 years, the COPD prevalence was 5.07%. Smoking, age, expectoration, locomotor activity limitation and frequency of respiration were risk factors of COPD in Hlai ethnicity.