Variation in prevalence and impact factors of chronic obstructive pulmonary disease among residents aged over 40 years in disease surveillance sites of Hubei province between 2014 and 2019: a comparison analysis

  Objective  To compare the prevalence and influencing factors of chronic obstructive pulmonary disease (COPD) among residents aged over 40 years in disease surveillance sites of Hubei province in 2014 and 2019 for providing evidence to COPD prevention and control.

  Methods  Two waves of survey, including face-to-face questionnaire interview and pulmonary function test, were conducted among 2 400 adults ( ≥ 40 years old) recruited in 4 disease surveillance sites in Hubei province using stratified multistage cluster sampling during December 2014 – March 2015 and November 2019 – December 2020. The modified Medical Research Council (mMRC) dyspnea scale and the Global Initiative for Chronic Obstructive Lung Disease (GOLD) stage were adopted in the study.

  Results  Among the 2 389 participants in 2014 – 2015 survey and 2 396 in 2019 – 2020, 213 and 272 COPD patients were identified, with the prevalence rate of 12.36% and 11.95% estimated through complex weighting, respectively. Compared to those in the survey of 2014 – 2015, the proportion of the COPD patients at GOLD stage I decreased (52.94% vs. 71.83%) but that of at GOLD stage II increased (38.97% vs. 22.07%) significantly in the survey of 2019 – 2020 (both P < 0.001). In terms of exposure to COPD-related factors among the participants in the survey of 2019 – 2020 and in comparison with those in the survey of 2014 – 2015, the smoking cessation rate increased from 18.92% to 23.11% (χ² = 4.164, P = 0.041); the rate of taking protective measures against occupational dust or hazardous gas increased from 18.53% to 54.69% (χ² = 14.321, P < 0.001); the percentage of using coal for heating decreased from 2.43% to 0.38% (χ² = 19.035, P＜0.001); the proportion of having the history of childhood severe respiratory infection decreased from 3.01% to 1.30% (χ² = 15.861, P < 0.001); and the detection rate of dyspnea decreased from 8.14% to 3.81% (χ² = 4.767, P = 0.029).

  Conclusion  No significant change was observed in the prevalence of COPD between 2014 and 2019 among the residents aged ≥ 40 years in surveillance sites of Hubei province but the prevalence of exposure to some COPD-related factors decreased significantly.