Determination of Association between the Decrease in Cholesterol Concentration and Sepsis in Patients Admitted in the ICU


Department of Pulmonary Medicine, Iran University of Medical Sciences and Health Services, TEHRAN-IRAN


Background: Sepsis remains a major cause of hospital-based mortality and morbidity, especially in ICU. It is estimated that there is 100000 to 500000 episodes of sepsis each year in the United States that involves 25%of patients admitted in the ICU, causing 80000 deaths each year. Some major variables may create discrepancies in predicting the outcome in critically ill patients. These are gender, preinfectious, preoperative, immune and/or genetic status, age, iatrogenic, and nosocomial events. In some studies, it is demonestrated that low circulating cholesterol concentration is associated with a greater mortality rate. Cholesterol is the basic element of cell membrane and is essential in extensive tissue repair processes for example in sepsis or after trauma. Materials and Methods: Setting: medical intensive care unit of Hazrate Rasool-e-Akram and Firoozgar hospitals. Design: crosssectional case series. Patients: totally 52 participants 26 of whom were septic and the rest were not (according to sepsis criteria). None of the patients had sepsis at the time of admission to the ICU. The patients were matched for demographic variables. Interventions: blood samples were drawn on the admission to the ICU and then twice weekly. Statistical Analysis: Results were expressed as (means±2SE) and analysed by SPSS version 10.00.The required tests were chi-square and t-tests. Results: The male to female ratio was 0.92. In septic patients only 38.4%of them had positive blood culture. The most common organism was gram negative enteric pathogen (Klebsiella and E. coli ). The average time of hospitalization in septic patients was 7.3± (1.8). There was no significant statistical difference between two groups (p value=0.537). The average primary cholesterol level in septic patients did not show significant differences with another group. However, the last cholesterol level was lower in septic patients. There were statistically significant correlations between the last cholesterol level and being septic. (p value=0.042 ). The mortality rate was higher in septic group than the other group ( p=0.000). Conclusion: Patients with low circulating cholesterol levels are at risk for lethal infections especially severe sepsis. The cause could be due to the role of cholesterol in membrane lipid, microviscosity, decreasing the exposure of membrane proteins, and reducing membrane function. Also, adipose tissue could function as macrophage cells and secrete proinflammatory mediators. (Tanaffos 2003; 2(7): 11-16)