Three-year follow-up of Interleukin 6 and C-reactive protein in chronic obstructive pulmonary disease

Author(s)

Ferrari, Renata ^[1] ; Tanni, Suzana E. ^[1] ; Caram, Laura M. O. ^[1] ; Correa, Corina ^[1] ; Correa, Camila R. ^[1] ; Godoy, Irma ^[1]

Affiliation

^[1] Univ Estadual Paulista, Fac Med Botucatu, UNESP, Disciplina Pneumol, Sao Paulo - Brazil

• Document type: Journal article
• Source: RESPIRATORY RESEARCH; v. 14, FEB 20 2013.
• Web of Science Citations: 45

Abstract

Background: Past studies have shown that mean values of Interleukin-6 (IL-6) and C-reactive protein (CRP) do not change significantly in COPD patients over a one-year period. However, longer period follow-up studies are still lacking. Thus, the aim of this study is to evaluate plasma CRP and IL-6 concentration over three years in COPD patients and to test the association between these inflammatory mediators and disease outcome markers. Methods: A cohort of 77 outpatients with stable COPD was evaluated at baseline, and 53 (mean FEV1, 56% predicted) were included in the prospective study. We evaluated Interleukin-6 (IL-6), C-reactive protein (CRP), six-minute walking distance (6MWD), and body mass index (BMI) at baseline and after three years. Plasma concentration of IL-6 was measured by high sensitivity ELISA, and CRP was obtained by high sensitivity particle-enhanced immunonephelometry. Results: IL-6 increased significantly after 3 years compared to baseline measurements {[}0.8 (0.5-1.3) vs 2.4 (1.3-4.4) pg/ml; p < 0.001] and was associated with worse 6MWD performance. In the Cox regression, increased IL-6 at baseline was associated with mortality {[}Hazard Ratio (95% CI) = 2.68 (0.13, 1.84); p = 0.02]. CRP mean values did not change {[}5 (1.6-7.9) vs 4.7 (1.7-10) pg/L; p = 0.84], although eleven patients (21%) presented with changes >3 mg/L in CRP after 3 years. Conclusions: The systemic inflammatory process, evaluated by IL-6, seems to be persistent, progressive and associated with mortality and worse physical performance in COPD patients. (AU)

• FAPESP's process: 10/08557-6 - Follow-up study of inflammatory markers in COPD patients in a three years period
• Grantee: Renata Ferrari
• Support Opportunities: Scholarships in Brazil - Doctorate
• FAPESP's process: 10/08527-0 - Follow-up study of inflammatory markers in COPD patients over three years period
• Grantee: Irma de Godoy
• Support Opportunities: Regular Research Grants