Relationship of hypolipidemia to cytokine concentrations and outcomes in critically ill surgical patients

Objective: To determine the relationship of hypolipidemia to cytokine conce ntrations and clinical outcomes in critically ill surgical patients. Design: Consecutive, prospective case series. Setting. Surgical intensive care unit of an urban university hospital. Patients: Subjects were 111 patients with a variety of critical illnesses, for whom serum lipid, lipoprotein, and cytokine concentrations were determi ned within 24 hrs of admission to a surgical intensive care unit. Controls were 32 healthy men and women for whom serum lipid, lipoprotein, and cytoki ne concentrations were determined. Interventions, Blood samples were drawn on admission to the intensive care unit, Predetermined clinical outcomes including death, infection subsequent to intensive care unit admission, length of intensive care unit stay, and magnitude of organ dysfunction were monitored prospectively. Measurements and Main Results: Measurements included total cholesterol, low -density lipoprotein cholesterol, high-density lipoprotein cholesterol, apo lipoproteins A-1 and B, phospholipid, triglyceride, interleukin-6, interleu kin-10, soluble interleukin-2 receptor, tumor necrosis factor-a, and solubl e tumor necrosis factor receptors p55 and p75. Mean serum lipid concentrati ons were extremely low: total cholesterol, 127 +/- 52 mg/dL; low-density li poprotein cholesterol, 75 +/- 41 mg/dL; high-density lipoprotein cholestero l, 29 +/- 15 mg/dL. Total, low-density lipoprotein, and high-density lipopr otein cholesterol concentrations and apolipoprotein concentrations inversel y correlated with interleukin-6, soluble interleukin-2 receptor, and interl eukin-10 concentrations, whereas the triglyceride concentration correlated positively with tumor necrosis factor soluble receptors p55 and p75. Clinic al outcomes were related to whether the admission cholesterol concentration was above (n = 56) or below (n = 55) the median concentration of 120 mg/dL . Each of the clinical end points occurred between 1.9- and 3.5-fold more f requently in the very low cholesterol (< 120 mg/dL) group. Nine patients (8 %) died during the hospitalization. Seven of the nine patients who died had total cholesterol concentrations below the median concentration of 120 mg/ dL. Conclusions. Low cholesterol and lipoprotein concentrations found in critic ally ill surgical patients correlate with interleukin-6, soluble interleuki n-2 receptor, and interleukin-10 concentrations and predict clinical outcom es.