Thyroid Dysfunction in Acute Ischemic Stroke in Medical Intensive Care Unit in Zagazig University Hospitals

Background: Stroke is a serious neurological disease and constitutes a major cause of death and disability throughout the world. It is the leading cause of adult disability in the United States and Europe and the second leading cause of death worldwide. Thyroid disorders can affect different risk factors of ischemic stroke and several studies have reported a high prevalence of thyroid disorders in patients with acute ischemic stroke. Objectives: This study was conducted to evaluate prevalence of undiagnosed thyroid disorders in patients with acute ischemic stroke and their relation to age and sex, study effect of thyroid disorders on each of different risk factors and their effect on the outcome of those patients. Patients and Methods: Out of 351 patients who were admitted to stroke subunit within 6 months which were diagnosed as stroke clinically and radiological. Only 131 eligible patients with acute ischemic stroke were recruited and followed up during ICU stay. All subjects were subjected to thorough history and general and neurological examination, assessment of severity score system was done in ischemic stroke using GCS and APACHE II score during first 24 hours of stroke onset, routine laboratory investigations, ECG, CT brain and/or MRI brain, arterial blood gases (ABG), TSH, free T4 and freeT3. Results: There was a high prevalence of undiagnosed thyroid disorders in patients with acute ischemic stroke (14.5%). Of them 4.6% had overt hyperthyroidism while subclinical hyperthyroidism (SCHyper) was 1.5%, overt hypothyroidism was 6.9% and subclinical hypothyroidism (SCHypo) was 1.5%. The increasing age over 60 years, female gender and smoking increase the prevalence and risk of developing thyroid disorders in patients with ischemic stroke. Overt/SCHyper increased relative risk of AF, fasting hyperglycemia and hypertension by 2.5, 1.3, and 2 folds respectively while overt/SCHypo increased relative risk of hypertension, hypercholesterolemia, high LDL, high TG by 2, 2.6, 2.7, and 2.6 folds respectively. A step wise logistic regression analysis revealed that AF (in overt/SCHyper) and LDL (in overt/SCHypo) were the most important risk factors predicting thyroid disorders in ischemic stroke patients. Thyroid disorders worsen GCS, APACHE II score, increased ICU stay and increased mortality by 1.4, 1.6, 2.4, and 1.7 folds respectively. Conclusion: Undiagnosed thyroid disorders was common in acute ischemic stroke patients and can worsen the outcome of acute ischemic stroke, so identification and management of these disorders may reduce recurrence of ischemic stroke and may improve their outcome.