T he cerebrovascular attack is the most common, life-threatening neurological disorder.It ranks 3 rd as a cause of death after heart disease and cancer, and 1 st in terms of morbidity [1].Inflammation is very significant in the pathogenesis of both hemorrhagic and ischemic stroke.Endothelial activation, disruption of the blood-brain barrier, leukocyte infiltration, and large amount of accumulation of oxidant and inflammatory mediators occur rapidly within hours and lead to secondary brain damage [2][3][4][5].Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are the most commonly used inflammatory markers in recent studies [6,7].Decreased high-density lipoprotein cholesterol (HDL-C) levels and increased monocyte counts are other markers of inflammation.Monocyte-to-HDL-C ratio (MHR), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) have been proposed as new inflammatory biomarkers [4,5,8,9].Hence, the aim is to investigate ESR, CRP, MHR, NLR, PLR, and ABSTRACT OBJECTIVE: This study aims to investigate inflammatory markers and their relationship with the degree of stenosis in ischemic stroke patients with carotid artery stenosis. METHODS:This retrospective case-control study was conducted with 70 newly diagnosed ischemic stroke patients and 70 age-and gender-matched healthy controls.Laboratory analyses were carried out including serum hemogram, biochemistry profiles, erythrocyte sedimentation rate, and C-reactive protein (CRP).Mean platelet volume (MPV), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and monocyte-to-high-density lipoprotein cholesterol ratio (MHR) values were calculated, and compared between the patients and healthy controls.Patients were divided into two groups according to the degree of arterial carotid stenosis.The degree of carotid stenosis was <50% in Group 1 and it was 50% and above in Group 2. RESULTS:In the patient group, neutrophil, monocyte, MPV, CRP, sedimentation, MHR, PLR, and NLR levels were significantly higher than the control group.There was no significant correlation between the level of carotid stenosis and inflammatory biomarkers.There was a significant correlation between the presentation NIHSS value and CRP, PLR, and NLR values.CONCLUSION: Inflammatory biomarker values were higher in stroke patients with carotid artery stenosis than in healthy individuals.However, they should neither be used to predict the degree of carotid artery stenosis.