Plasma l-carnitine and risks of cardiovascular events and recurrent stroke after ischemic stroke: A nested case-control study.

ABSTRACT

BACKGROUND AND AIMS: l-Carnitine was suggested to prevent the progression of atherosclerosis, myocardial and neurologic injury, and exhibited cardioprotective effects. However, epidemiological data on circulating l-carnitine and risks of cardiovascular events in the setting of stroke is rare. We aimed to explore the relationships between plasma l-carnitine and cardiovascular events and stroke recurrence after ischemic stroke in a nested case-control study. METHODS AND RESULTS: A total of 323 cardiovascular events (including 264 recurrent strokes) and 323 matched controls (free of recurrent cardiovascular events) were included. Study outcomes included cardiovascular events and recurrent stroke after ischemic stroke. Plasma l-carnitine concentrations were measured by ultra-high-performance LC-MS/MS. Conditional logistic regression models were used to estimate odds ratios (ORs) of stroke outcomes. Plasma l-carnitine was inversely associated with cardiovascular events (OR = 0.69, 95% CI 0.57-0.84 per SD) and recurrent stroke (OR = 0.72, 95% CI 0.58-0.88 per SD) after adjusting for established risk confounders. Compared with the lowest tertile of l-carnitine, adjusted ORs of cardiovascular events and recurrent stroke for participants in the highest tertiles were 0.35 (95% CI 0.21-0.57) and 0.36 (95% CI 0.21-0.62), respectively. In addition, l-carnitine provided incremental predictive ability beyond established risk factors, shown by increase in C statistics, net reclassification improvement and integrated discrimination improvement. CONCLUSIONS: Higher l-carnitine levels were associated with lower risks of cardiovascular events and recurrent stroke after ischemic stroke. Our findings provided evidence supporting plasma l-carnitine as a potential prognostic marker in risk discrimination and stratification in patients with ischemic stroke. TRIAL REGISTRATION Clinicaltrials.gov as NCT01840072. URL https//www. CLINICALTRIALS gov.