Nontraditional Lipid Variables Predict Recurrent Brain Ischemia in Embolic Stroke of Undetermined Source

The aims of this study are, first, to calculate the risk of brain ischemia recurrence and embolic source diagnosis in the follow-up of patients with ESUS (embolic stroke of undetermined source) and, second, to identify the predictors of these events including cardiologic, laboratory, and clinical factors.

A retrospective observational cohort study of stroke patients admitted to the stroke unit in a single tertiary hospital from 2012 to 2014 was performed. Patients fulfilling ESUS criteria were identified and followed by medical history review until March 2016. Statistical analysis comprised Kaplan-Meier analysis and Cox proportional hazards multivariate analysis including clinical characteristics, cardiologic data, and blood test results.

One hundred and thirteen patients, 8.3% of the overall stroke patients, filled ESUS criteria and they were younger, had less vascular risk factors, and suffered milder strokes than the remainder of stroke patients. Median follow-up of ESUS was 25.6 months. Risk of brain ischemia recurrence was 8.4, 10.8, and 15% at 12, 24, and 36 months, respectively, and was associated to age (HR 1.07, P = .027) and to a higher total cholesterol (TC)/high-density lipoprotein (HDL)-cholesterol (HR = 1.38, P = .002) and low-density lipoprotein (LDL)-cholesterol/HDL-cholesterol ratios (HR = 1.48, P = .001). The risk of major embolic source diagnosis was 6.7, 7.8, 13.6% at 12, 24, and 36 months, and was associated to female sex (HR = 6.05, P = .021).

Brain ischemia recurrence increases with age and increased values of nontraditional lipid variables, TCHDLr and LDLHDLr, in ESUS patients, and women are more frequently diagnosed with a major embolic source in the follow-up.