Inflammatory biomarkers predicting prognosis in patients with acute dyspnea

Abstract

Objective/purpose: The objective was to identify inflammatory biomarkers that predict risk of 90-day mortality in patients with acute dyspnea.

Method: We analyzed 25 inflammatory biomarkers, in plasma, in 407 adult patients admitted to the emergency department (ED) with acute dyspnea and related them to risk of 90-day mortality using Cox proportional hazard models adjusted for age, sex, oxygen saturation, respiratory rate, C-reactive protein, and Medical Emergency Triage and Treatment System-Adult score.

Results: Fifty patients (12%) died within 90 day from admission. Two strong and independent biomarker signals were detected: The hazard ratio (95% confidence interval) for 90-day mortality per 1-SD increment of interleukin-8 (IL-8) was 2.20 (1.67-2.90) (P = 2.5 × 10(-8)) and for growth differentiation factor-15 (GDF-15) was 3.45 (2.18-5.45) (P = 1.3 × 10(-7)) A Biomarker Mortality Risk Score (BMRS) summing standardized and weighted values of IL-8 and GDF-15 revealed that of patients belonging to quartile 1 (Q1) of the BMRS, only 1 patient died, whereas 32 patients died among those belonging to quartile 4. Each 1-SD increment of the BMRS was associated with a hazard ratio of 3.79 (2.50-5.73) (P = 2 × 10(-10)) for 90-day mortality, and the point estimate was 13 times higher in Q4 as compared with Q1 of the BMRS (P(trend) over quartiles = 2 × 10(-6)).

Conclusion: Interleukin-8 and GDF-15 are strongly and independently related to risk of 90-day mortality in unselected patients admitted to the ED because of acute dyspnea, suggesting that they may guide first-line physicians at the ED in risk assessment which in turn could lead to more accurate level of care and treatment intensity.

Figure

Kaplan-Meier plot showing cumulative mortality during 90 days of follow-up. Quartile 1 denotes the lowest values of the BMRS; and Quartile 4, the highest values.