Objective: To study the relationship between serum high-density lipoprotein cholesterol (HDL-C), total serum cholesterol, and nosocomial infection in patients undergoing general surgery.
Design: Prospective cohort study, with an extended follow-up to 1 month after hospital discharge.
Setting: The general surgery service of a tertiary hospital.
Main outcome measure: Nosocomial infection, mainly surgical-site infection (SSI), urinary tract infection, respiratory tract infection (RTI), and bacteremia.
Patients: 1,267 surgery patients aged 10 to 92 years.
Results: 182 subjects acquired 194 nosocomial infections, a cumulative incidence of 14.5%; most (116, 62.3%) were postoperative wound infections. There was an increase in infection risk at low levels of HDL-C, and both low and high total cholesterol levels. After adjusting simultaneously for several confounders, including total cholesterol, low levels of HDL-C (< or = 20 mg/dL) yielded an odds ratio (OR) of 2.2 (95% confidence interval [CI95], 0.6-7.9) for SSI and an OR of 10.3 (CI95, 0.7-151.5) for RTI. Otherwise, no trend was observed between HDL-C levels and infection risk, and no increased risk of nosocomial infection was observed for HDL-C values in the range of 21 to 49 mg/dL. Serum cholesterol showed a U-shaped relationship with nosocomial infection risk. Both low levels (below 102 mg/dL) and high levels (above 290 mg/dL) of total cholesterol were associated with a higher risk of SSI (mainly those caused by gram-negative bacteria) and RTI in comparison with the reference group (139-261 mg/dL).
Conclusions: Serum HDL-C and total cholesterol seem to be associated with the risk of nosocomial infection in surgical patients.