. 2021 Jan 9;159(6):2244–2253. doi: 10.1016/j.chest.2021.01.004

Table 2.

Protein Biomarker Associated With Cross-sectional and Longitudinal COPD Outcomes

Biomarker	Lung Function			Imaging		Exacerbations
Biomarker	FEV₁ or FEV₁/FVC	Decline FEV₁	Dlco	Emphysema	Emphysema Progression	Frequent and Previous	Future
sRAGE	↑^b	↑^b	↓^a	↓^b	↓^b	↑^b	↑^a
IL-6	↑^b	↑^a	NS	↑^a	↑^a	NS	NS
IL-8	↑^b	NS	↑^a	NS	↑^a	↑^b	NS
Fibrinogen	↓^b	↑^b	NS	↑^b	↓^b	↑^b	↑^a
CRP	↓^b	↑^a	NS	↑^b	↑^a	↑^b	↑^a
SPD	↓^b	↑^a	NS	↓^b	↑^a	↑^b	NS
CC16	↑^b	↓^b	NS	↑^a	↓^a	NS	↑^a
APOA1	↑^a	NS	↑^a	NS	NS	NS	NS

↑ = positive biomarker – clinical outcome association; ↓ = negative biomarker – clinical outcome association; APOA1 = apolipoprotein A1; CC16 = club cell secretory protein; CRP = C-reactive protein; Dlco = diffusing capacity for carbon monoxide; NS = not significant biomarker – clinical outcome association; SPD = surfactant protein D; sRAGE = soluble receptor for advanced glycation.

No replication.

Replication in two cohorts.