[Analysis on passive smoking exposure in adults aged 40 years and above in China, 2019-2020].

To understand the passive smoking exposure status in adults aged ≥40 years in China. Local residents aged ≥40 years were enrolled as study subjects from 125 areas of chronic obstructive pulmonary disease (COPD) surveillance during 2014-2015 and 2019-2020 in 31 provinces of China. A total of 74 559 adults aged ≥40 years were selected through multi-stage stratified cluster sampling for a face to face questionnaire survey and the data from 64 142 study subjects were used for the analysis. The passive smoking exposure rate, the proportions of the adults reporting passive smoking exposure at four types of places and the proportion of the adults living with daily smokers were described by using complicated sampling weighting method, the related factors were analyzed and the results were compared with the data of COPD surveillance during 2014-2015. The passive smoking exposure rate in the adults aged ≥40 years was 46.4% (95%: 44.1%-48.8%) in China during 2019-2020, and the rate was higher in women (47.2%, 95%:44.8%-49.7%) than in men (44.8%, 95%:42.0%-47.6%) and lower in the older people. The office workers had the highest passive smoking exposure rate. The proportions of those reporting passive smoking exposure at homes, workplaces, restaurants, and public transports were 24.3% (95%:22.2%-26.4%)、23.3% (95%:21.1%-25.5%)、6.6% (95%:5.3%-7.9%) and 2.2% (95%:1.6%-2.7%). The higher education level the adults had, the less passive smoking exposure at home they reported. The proportions of those living with daily smokers before 14 years old and since 14 years old were 56.4% and 59.2%. Compared with the data during 2014-2015, the overall passive smoking exposure rate in the adults aged ≥40 years during 2019-2020 showed an increase, and the difference was not significant (0.356); The passive smoking exposure rate at homes declined, but the exposure rate at workplaces increased, with the biggest increase found in those being engaged in farming, forestry, husbandry, fishery and water conservancy. Multivariate analysis indicated that the factors influencing the passive smoking exposure and the exposure proportions at different places included gender, age, occupation, and education level. The passive smoking exposure rate in China is still high, especially in those being engaged in farming, forestry, husbandry, fishery and water conservancy. It is necessary to strengthen supervision of the enforcement of current smoking bans in public places and promote the legislation of ban smoking in public places. More attention should be paid to smoking ban and protection against passive smoking exposure in women, people with lower education level and people being engaged in in farming, forestry, husbandry, fishery and water conservancy.