Comparison of the inflammatory parameters between the patients with stroke and with association of obstructive sleep-apnea syndrome and stroke

Introduction: It is believed that increase in the free oxygen species, release of the proinflammatory cytokines, activation of the sympathetic nervous systme, endothelial dysfunction, and elevated blood pressure directly contribute to development of stroke in the patients with obstructive sleep-apnea syndrome (OSAS). Stroke is a condition with high mortality and morbidity rates, and its association with OSAS is common. Inflammation plays important role in physiopathology of both stroke and OSAS. Objectives: It was planned to evaluate and compare the inflammatory parameters in the patients with ischemic stroke and those with association of ischemic stroke and OSAS. Our secondary objective was to evaluate the relationship between these parameters separately evaluated in both groups of patients with etiology, prognosis, and severity of disease. Materıals and Methods: The study included the patients admitted in the Neurology Department or stroke unit between January 2019 and January 2021 with diagnosis of ischemic stroke. After obtaining approval from the Ethics Committee, the study was conducted based on the inclusion and exclusion criteria. In addition to the patients with ischemic stroke, the study also included those with association of ischemic stroke and OSAS. The control group consisted of the age- and sex-matched healthy subjects without any neurological symptom and whose the conditions mentioned above were excluded. The parameters to be examined were planned to include leukocytes, hemoglobin, hematoctit, MCH, MCV, MPV, platelets, neutrophyles, lymphocytes, monocytes, High-density lipoprotein (HDL), RDW, ferritin, C- Reactive Protein (CRP), D-Dimer, fibrinogen, neutrophyle/lymphocyte ratio, lymphocyte/monocyte ratin, platelet/lymphocyte ratio, monocyte/HDL ratio, and RDW/lymphocyte ratio. All patients underwent detailed examination and their NIHSS was estimated. They were evaluated as anterior-posterior system based on the vascular imaging and etiology was determined using TOAST classification. For the group of patients with association of stroke and OSAS, their sleep disorders were graded by polysomnography. The inflammatory parameters were compared among all these subgroups. Results: The study included 100 patients with diagnosis of ischemic stroke, 70 patients with association of ischemic stroke and OSAS, and 100 healthy individual as the control group. The parameters showing significant difference in the comparison between the general disease groups (OSAS, Stroke-OSAS) and the control group included leukocytes, hemoglobin, platelets, neutrophyles, monocytes, HDL, RDW, ferritin, CRP, fibrinogen, and ratios of neutrophyles/lymphocytes, lymphocytes/monocytes, platelets/lymphocytes, and monocytes/HDL. In the evaluation based on TOAST classification (for etiology), the only parameter showing significant statistical difference was the neutrophyles/lymphocytes ratio. When evaluation was made based on NIHSS comparison neutrophyles, lymphocytes, ratios of neutrophyles/lymphocytes, platelets/lymphocytes, and RDW/lymphocytes were found to be significantly different in the stroke groups whereas ferritin level was found to be significantly different in the Stroke-OSAS group. D-Dimer, fibrinogen, and RDW value were found to be significantly different according to the degree of sleep-related respiratory disorders in the Stroke-OSAS group. In the evaluation of the ratios, the neutrophyles/lymphocytes ratio as well as lymphocytes/monocytes ratio were found to be the ratios being helpful to determine size of the infarction (by means of NIHSS), and extent of the disease especially in the Stroke-OSAS association. Discussion: Inflammatory mechanisms play role in OSAS included in the risk factors for cerebrovascular diseases. Especially in the patients with association of stroke and OSAS, the inflammatory parameters enabled us to have opinion on the presence of OSAS by comparing with those in the patients with isolated stroke. Direct relationship between stroke and OSAS was shown by the strong correlation between the risk factors for and incidence of ischemic stroke and apnea-hypopnea index. In comparison in pairs (stroke-control, OSAS stroke-control), it was seen that the presence of OSAS did not contribute to inflammation in stroke. Examining the parameters being able to be evaluated with routine blood analyses is a cheap, objective, and practical method; thus they can enable early diagnosis. In conclusion, our evaluation based on the parameters we evaluated enabled us to have information on both etiology and prognosis.