Association between cholesterol levels and infections after ischemic stroke

Multiple studies have suggested an immunomodulatory role of cholesterol. We investigated whether cholesterol levels are associated with the risk of infectious complications (ICs) in acute ischemic stroke patients.

A single-center prospective cohort was analyzed. Total (TOTc), low-density lipoprotein cholesterol and high-density lipoprotein cholesterol levels were measured within 24 h from admission. The outcome of interest was the occurrence of any IC (pneumonia, urinary tract infection, sepsis, other infection) during hospitalization. Predictors of ICs were investigated with multivariable logistic regression.

A total of 603 patients were included (median age 78 years, 49.3% males), of whom 134 (22.2%) developed an IC. Subjects with ICs had lower TOTc compared with patients without ICs (median 157 vs. 173 mg/dL; P < 0.001). When TOTc was stratified in quartiles, we observed a linear decrease in the prevalence of ICs with higher TOTc levels (Q1, <144 mg/dL, 32.7%; Q2, 145-168 mg/dL, 24.7%; Q3, 169-197 mg/dL, 17.8%; Q4, >197 mg/dL, 13.3% P < 0.001). The inverse relationship between TOTc and ICs remained significant after adjustment for confounders in logistic regression [odds ratio (OR) for 10 mg/dL increase, 0.92; 95% confidence intervals (CI), 0.87-0.97; P = 0.001]. This association was also confirmed for low-density lipoprotein cholesterol (OR, 0.93; 95% CI, 0.88-0.99; P = 0.013) and high-density lipoprotein cholesterol (OR, 0.85; 95% CI, 0.73-0.98; P = 0.026) and was not mediated by statin treatment.

Higher cholesterol levels are independently associated with lower risk of ICs in ischemic stroke patients. Further studies are needed to confirm our findings and characterize the biological mechanisms underlying this association.