Abstract Rationale Chronic Obstructive Pulmonary Disease (COPD) is a heterogeneous lung disease that includes a proportion of patients with asymptomatic airflow obstruction. However, the association between asymptomatic airflow obstruction and all-cause mortality remains scarce. Objectives To evaluate the risk of all-cause mortality associated with asymptomatic airflow obstruction relative to normal spirometry. Methods Participants were drawn from the National Health and Nutrition Examination Survey (NHANES) (NHANES III and NHANES 2007-2012) and the UK Biobank studies. This analysis included data from participants aged 20 to 79 years who had eligible spirometry data, complete physical measurements, and follow-up data on mortality. Asymptomatic airflow obstruction was defined as a pre-bronchodilator FEV1/FVC 0.70 without symptoms of chronic cough, chronic sputum, or dyspnea. Cox proportional hazards models were applied to evaluate the association between asymptomatic airflow obstruction and all-cause mortality risk. Subgroup analyses were stratified by sex, age, and smoking status. Measurements and Main Results A total of 12 474 participants in the NHANES study (with a median follow-up of 338 months) and 48 736 participants in the UK Biobank study (with a median follow-up of 176.5 months) were included in the baseline analysis. In both studies, participants with asymptomatic airflow obstruction had a higher risk of all-cause mortality (NHANES study: HR = 1.19 95% CI: 1.08-1.30, P 0.001; UK Biobank study: HR = 1.31 95% CI: 1.03-1.68, P = 0.031) compared to participants with normal spirometry after adjusting covariates. Consistent results were observed in subgroup analyses of female(NHANES study: HR = 1.18 95% CI: 1.01-1.37, P = 0.033; UK Biobank study: HR = 1.55 95% CI: 1.02-2.36, P = 0.041) and participants aged ≥50 years(NHANES study: HR = 1.20 95% CI: 1.09-1.33, P 0.001; UK Biobank study: HR = 1.32 95% CI: 1.02-1.69, P = 0.033) between asymptomatic airflow obstruction and normal spirometry in both two studies. Conclusions Asymptomatic airflow obstruction is positively correlated with the risk of all-cause mortality, suggesting that participants with airflow obstruction may have poor health despite not showing respiratory symptoms. Early detection and management for patients with asymptomatic airflow obstruction are crucial. This abstract is funded by: None
hou et al. (Fri,) studied this question.