Влияние Начального Уровня Свободного Трийодтиронина В Сыворотке Крови На Тяжесть Инсульта И Его Последствия У Пациентов С Атеротромботическим Ишемическим Инсультом

Abstract

Background. According to recent studies, thyroid hormones may have various effects on stroke severity, course and outcome, but underlying mechanisms of this association are still unclear. The purpose was to determine the relationship of thyroid hormones during stroke onset with stroke severity and outcome in a clinical study. Materials and methods. In this study, 168 adult patients with acute ischemic stroke were enrolled. Concentrations of free triiodothyronine (fT3), free thyroxine (fT4), thyroid-stimulating hormone and basic stroke risk factors were assessed during 24 h from symptoms onset. Neurological deficit was evaluated by Scandinavian Stroke Scale (SSS). Disabling deficit was defined as Modified Rankin Scale score ≥ 3 points six months after stroke. Results. ANOVA showed that SSS scores were significantly higher in patients with fT3 level in quartile IV (≥ 5.35 pmol/l) compared to quartiles II-III (SSS median 48 vs. 37, p = 0.0481) and especially to quartile I (≤ 3.4050 pmol/l, SSS median 48 vs. 30, p = 0.0018). In patients without prior stroke (n = 124), fT3 independently affected baseline SSS score (corrected R 2 = 0.49, p < 0.0001). The analysis showed that in patients with atherothrombotic stroke subtype (n = 108), fT3 level was an independent risk factor for unfavourable stroke outcome (odds ratio = 0.3498, 95% confidence interval 0.1235-0.9904). According to ROC-analysis, fT3 level < 4.44 pmol/l was a predictor of disabling deficit (AUC = 0.727, p = 0.003). Conclusions. The study showed that a low serum free triiodothyronine level during stroke onset negatively affects the stroke severity in first stroke patients and may be a predictor of its unfavourable outcome. In patients with atherothrombotic stroke, lower baseline fT3 levels were independently associated with poor outcome after 6 months. Beneficial effects of additional fT3 supplement during stroke should be assessed in future studies.