Relationship between airway obstruction and C-reactive protein levels in a community-based population of Korea

OBJECTIVE: To examine the relationship between high-sensitivity C-reactive protein (hs-CRP) levels and lung function in a community-based cohort of South Korea.

DESIGN: The Ansung-Ansan cohort database (an ongoing prospective study of a community-based population) was used in the analysis. We defined airway obstruction as the ratio between forced expiratory volume in 1 sec:forced vital capacity ratio (FEV₁:FVC) of <95% of the predicted value for a healthy person. We also used the serum level of hs-CRP as a marker of inflammation. Multivariate analysis was performed with adjustment for the clinical characteristics of the participants.

RESULTS: A total of 5528 individuals were eligible for the study. The average age was 55.1 years, and 47.8% were males. The prevalence of airway obstruction was 9.0%, and the mean hs-CRP level was 1.51 mg/dl. Serum hs-CRP levels increased with the severity of airway obstruction, and the latter worsened with an increase in the hs-CRP level. In multivariate analysis, as the hs-CRP level increased, FEV₁ and FVC decreased. A higher FEV₁:FVC ratio was associated with lower hs-CRP levels in males.

CONCLUSION: Higher hs-CRP levels were associated with decreased FEV₁ and FVC in a general population of Korea. The FEV₁:FVC ratio decreased with an increase in the hs-CRP level in males.