This is a case control cross-sectional study conducted on 200 Egyptian patients presented AIS, within the first 24 h. Patients were recruited from the Neurology Departments in Fayoum University Hospital, Fayoum General Hospital and Fayoum Health Insurance Hospital in the period from April 2015 to February 2017. Patients were defined according to the World Health Organization (WHO) criteria  and had symptom onset within 24 h. We excluded patients with Parkinson disease, recurrent ischemic stroke, intra-cerebral hemorrhage, medical illness, or current medications that influence serum IGF-I levels such as dwarfism, acromegaly, chronic kidney diseases, liver diseases, and high dose of estrogen. We excluded also patients suffering from congestive heart failure, malignant tumor, renal insufficiency, severe edema, febrile disorders, systemic infections, history of recent surgery, or trauma during the preceding 2 months and autoimmune diseases.
One hundred adults were enrolled in our study as a control group. They came to the neurology clinic seeking medical advice for headache or spondylosis. They were matching the cohort group in age, sex, and conventional vascular risk factors.
All patients and controls were subjected to detailed history taking, general and full neurological examination, assessment of severity of neurological deficit of stroke according to National Institute of Health Stroke Scale (NIHSS) scores ranging from 0 to 42; with higher values reflecting more severe neurologic damage . Stroke subtypes were classified according to Trial of Org 10,172 in Acute Stroke treatment (TOAST) criteria  that denote 5 subtypes of ischemic stroke: large-artery atherosclerosis, cardio-embolism, small-vessel occlusion, stroke of other determined etiology, and stroke of undetermined etiology. To confirm the diagnosis of AIS, all patients underwent a magnetic resonance imaging (MRI) with diffusion scan (stroke protocol) on Titan Toshiba 1.5 Tesla of the brain in the Radiology Department, Fayoum University Hospital.
Routine laboratory investigations were also performed including complete blood count (CBC), serum C-reactive protein (CRP) level, erythrocyte sedimentation rate (ESR), liver and kidney function tests to exclude the presence of systemic or metabolic disorders, fasting blood glucose level, and finally serum cholesterol.
Regarding the serum IGF-1, venous blood samples were collected within the first 24 h of the AIS in the fasting state. We collected 5 ml of venous blood in vacutainer collection tubes. Samples were left to clot for 30 min before centrifugation; the latter was applied for 15 min at approximately 1500×g. Serum was removed and assayed immediately or stored at − 80 °C until analysis.
IGF-1 was measured using DRG IGF-1600 ELISA Kit (Reference # EIA-4140). The kit is a solid phase enzyme-linked immunosorbent assay (ELISA) based on the principle of competitive binding. Patient samples, standards, and controls were acidified and neutralized prior to the assay procedure. The micro titer wells were coated with a monoclonal antibody directed towards an antigenic site on the IGF-1 molecule. The pre-treated sample was incubated at room temperature with the conjugate (biotinylated IGF-1). The wells were washed then incubated with enzyme complex (Streptavidin-HRP-complex). After addition of the substrate solution, the concentration of IGF-1 was calculated in a reverse proportional way to the intensity of the color developed.
The study was approved by the Faculty of Medicine, Fayoum University Research Ethical Committee. All participants either patients or controls were informed about the objectives of the study, the examination, and the investigations. The confidentiality of their information and their right not to participate in the study were considered. Written informed consents were obtained from all of them.
Date of ethical committee15/4/2015.
Session number-13 N (D58).
Data were collected and coded into Microsoft Access, and data analysis was performed using SPSS software version 18 in windows 7. Simple descriptive analysis was performed in the form of numbers and percentages for qualitative data. Quantitative data were described in the form of arithmetic means, standard deviation (SD), and range. Independent Student’s t test was used to compare two independent groups of quantitative data as age and serum level of IGF-1. Chi-square test was used to compare qualitative groups such as sex. Bivariate (Pearson) correlation test was used to assess the association between variables. The level p < 0.05 was considered the cut-off value for significance.