However, when patients with <48 hours ICU stay were compared to those with ≥48 hours ICU stay, there were no significant differences with regard to age (P = 0.457), gender (P = 0.205), lung injury (P = 0.248), source of infection (P = 0.446), or LBP serum levels at study entry (P = 0.792). This evidence concerns the gene LBP and infection.