Plasma cell-free DNA in patients needing mechanical ventilation

Area of Science:

• Critical Care Medicine
• Molecular Diagnostics
• Prognostic Biomarkers

Background:

• Plasma cell-free DNA (cfDNA) concentrations increase in various diseases, showing prognostic value in critically ill patients.
• Mechanical ventilation and associated pathophysiological processes may elevate plasma cfDNA levels.
• This study investigates cfDNA levels and their prognostic significance in mechanically ventilated patients.

Purpose of the Study:

• To evaluate plasma cell-free DNA (cfDNA) concentrations in mechanically ventilated critically ill patients.
• To determine the prognostic value of cfDNA levels for 90-day mortality.
• To assess cfDNA as an independent predictor of mortality in this patient cohort.

Main Methods:

• Prospective study of 580 mechanically ventilated critically ill patients.
• Blood samples collected at admission (Day 0) and Day 2.
• Plasma cfDNA measured using real-time quantitative PCR for the β-globin gene, reported as genome equivalents (GE)/ml.

Main Results:

• Median plasma cfDNA at admission was 11,853 GE/ml, with similar levels on Day 2.
• Non-survivors had significantly higher admission cfDNA (16,936 GE/ml) than survivors (10,026 GE/ml) (P < 0.001).
• cfDNA concentration >16,000 GE/ml independently predicted 90-day mortality (aOR 2.16; 95% CI 1.37-3.40).

Conclusions:

• Plasma cfDNA levels are significantly higher in non-survivors compared to survivors.
• Baseline plasma cfDNA serves as an independent predictor of 90-day mortality.
• The overall clinical benefit of plasma cfDNA as a prognostic marker in this setting appears limited.