LDL Cholesterol Predicts Ischemic Stroke in Atrial Fibrillation
The best LDL-C cut-off value to predict stroke was 2.48 mmol/L.
Low-density lipoprotein cholesterol (LDL-C) may be an independent predictor of ischemic stroke in patients with atrial fibrillation (AF), according to results from a study conducted in Shanghai, China, and published in the American Journal of Cardiology.1
Vascular disease has been identified as a risk factor for ischemic stroke in patients with AF, and it has been incorporated into the CHA2DS2-VASc (congestive heart failure, hypertension, age ≥75 [doubled], diabetes mellitus, stroke [doubled]-vascular disease, and sex category [female]) score as such.2,3 Increased stroke risk has also been linked to carotid intima-media thickness and carotid plaque in patients with AF.4
Taken together, these findings suggest atherosclerosis is an important factor in predicting ischemic stroke risk in this patient group.
LDL "participates in the promotion, development, and progression of atherosclerosis through a pathway that involves endothelial cell dysfunction, lipoprotein oxidation, foam cell formation, and inflammatory responses," the researchers wrote.5 "However, the role of [LDL-C] in predicting ischemic stroke in AF patients has not been explored."
They examined this relationship in a sample of 424 patients with nonvalvular AF who presented to the emergency department with acute ischemic stroke. Patients with AF without ischemic stroke (n = 391) served as controls. None of the patients had received treatment with antithrombotic agents.
The findings revealed that LDL-C independently predicted ischemic stroke in patients with AF (adjusted odds ratio [OR], 2.004; 95% CI, 1.624-2.473; P <.001). The best LDL-C cutoff value to predict this outcome was 2.48 mmol/L, with 56.3% sensitivity and 66.3% specificity (area under the curve, 0.651; P <.001). Results of a subgroup analysis based on different CHA2DS2-VASc scores, which adjusted for the various components that comprise the score, showed that the predictive value of LDL-C remained significant in patients who had a CHA2DS2-VASc score of 5 or less, but not in those whose score was 6 or higher.
"In conclusion, LDL-C was an independent predictor of ischemic stroke, which could potentially refine stroke stratification in AF patients," the researchers wrote.
"The addition of LDL-C information could provide incremental predictive value for risk of ischemic stroke, over the CHA2DS2-VASc risk score, which is solely based on clinical variables."
To validate these findings, future research should include a prospective design and a larger sample.
- Zhiyong Qi, Hua Chen, Zhichao Wen, et al. Relation of low-density lipoprotein cholesterol to ischemic stroke in patients with nonvalvular atrial fibrillation [published online January 25, 2017]. Am J Cardiol. doi: 10.1016/j.amjcard.2016.12.031
- Anandasundaram B, Lane DA, Apostolakis S, Lip GY. The impact of atherosclerotic vascular disease in predicting a stroke, thromboembolism and mortality in atrial fibrillation patients: a systematic review. J Thromb Haemost. 2013;11(5):975-987. doi: 10.1111/jth.12177
- Camm AJ, Lip GY, De Caterina R, et al; ESC Committee for Practice Guidelines (CPG). 2012 focused update of the ESC guidelines for the management of atrial fibrillation: an update of the 2010 ESC Guidelines for the management of atrial fibrillation. Developed with the special contribution of the European Heart Rhythm Association. Eur Heart J. 2012;33(21):2719-2747. doi: 10.1093/eurheartj/ehs253
- Bekwelem W, Jensen PN, Norby FL, et al. Carotid atherosclerosis and stroke in atrial fibrillation: The Atherosclerosis Risk in Communities Study. Stroke. 2016;47(6):1643-1646. doi: 10.1161/STROKEAHA.116.013133
- Berliner JA, Navab M, Fogelman AM, et al. Atherosclerosis: basic mechanisms. Oxidation, inflammation, and genetics. Circulation. 1995;91(9):2488-2496. doi: 10.1161/01.CIR.91.9.2488