Little is known about chronic obstructive pulmonary disease (COPD) in Chinese nonsmokers. The present study aimed to investigate the profiles of COPD among nonsmokers based on the Chinese Epidemiological Survey of COPD (CESCOPD).In the CESCOPD, 20,245 subjects aged 40 yrs or older were interviewed with questionnaires and spirometry tests. Subjects with a post-bronchodilator forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) ratio of ,0.70 were identified as having COPD. Data of 12,471 nonsmokers and 1,024 smoking COPD patients were analysed in the current study.The overall prevalence of COPD among nonsmokers was 5.2% (95% confidence interval 4.8-5.6). Being male, of advanced age, lower body mass index (BMI) and lower educational level, having exposure to environmental tobacco smoke, coal and/or biomass smoke, poor ventilation in the kitchen, a family history of respiratory disease and recurrent childhood cough were all independently associated with a higher risk of having COPD among nonsmokers. Nonsmokers with respiratory symptoms without airflow limitation showed a somewhat different pattern of risk factors. Nonsmokers with COPD were less likely to present with chronic productive coughs and lower BMI, while more likely to have received a physician diagnosis of asthma and respiratory diseases in childhood, than smokers with COPD.Chronic obstructive pulmonary disease is prevalent among Chinese nonsmokers, and nonsmoking chronic obstructive pulmonary disease may have different profiles from smoking chronic obstructive pulmonary disease.

These results suggest a statistically significant, though weak, inverse relationship between lung function and blood pressure in Chinese men and women. This association is largely attributable to age and is present prospectively only in women.

Background Many studies have shown that active smoking leads to an increasing incidence of chronic obstructive pulmonary disease (COPD). However, studies interested in the effects of secondhand smoke exposure (SHS exposure) on COPD were less or underappreciated. Methods A systematic review and meta-analysis was conducted to investigate the association between SHS exposure and the risk of COPD. Three databases (PubMed, Embase and Web of Science) were searched to obtain data. After assessing the study quality, stratified analyses were performed according to the region, gender, and duration of exposure. Cochran’s Q and I 2 were utilized for heterogeneity assessment. To assess publication bias, we used a funnel plot and Egger’s test. Results A total of 15 studies (6 cross-sectional studies, 6 case-control studies, and 3 cohort studies) with 25,592 participants were involved in this meta-analysis. This study showed that SHS exposure was associated with an increased risk of COPD (odds ratio (OR): 2.25, 95% CI: 1.40–3.62, I 2 = 98%, p < 0.01 for heterogeneity based on a random-effects analysis model), especially in those with a longer time exposure of more than 5 years was 4.38 (95% CI: 1.28–15.00, I 2 = 89%, p < 0.01 for heterogeneity based on a random-effects analysis model). In addition, SHS exposure also increases the risk of COPD in women (odds ratio (OR): 2.02, 95% CI: 1.52–2.67, I 2 = 0%, p = 0.89 for heterogeneity based on a random-effects analysis model). Conclusion The findings suggest that SHS exposure is associated with the risk of COPD, especially for individuals with a long time exposed. Trial Registry Prospero CRD42022329421.