Yaoundé is the political capital of Cameroon, with about 1.5 million inhabitants. Our study took place in two out of five tertiary hospitals with permanent neurologists and cardiologists, namely the Central Hospital and the General Hospital. Most stroke patients in the city are referred to these facilities. This was a prospective observational cohort study lasting 90 days after the stroke. Patients were recruited from February 1st until May 30th, 2015. We included all adult patients received for a sudden onset of neurological deficit with a brain computerized tomography (CT) scan suggestive of cerebral infarction or intra cerebral haemorrhage. We excluded any patient who did not have a brain CT scan or whose scan featured other findings such as meningeal haemorrhage and cerebral venous thrombosis. Our sampling method was consecutive and exhaustive.
Data were collected using a pre-established data sheet and patients or relatives were contacted through phone call on five occasions. The first contact was made at the patient’s bed within 24 hours of admission. During this contact, the following information was obtained from the patient or his entourage: demographic data (age, sex, marital status, level of education, dominant side), the recruitment hospital and service where the patient was admitted, the patient medical history (high blood pressure, diabetes, dyslipidaemia, smoking, alcoholism, history of stroke and the duration between that and the current episode, history of embolic heart disease, human immunodeficiency virus infection or sickle cell disease), the time in hours between the onset of symptoms and arrival at a health facility, the time taken to arrive at the recruitment hospital and the delay in performing the brain CT scan. For patients whose symptoms were noticed on waking, we considered that they started at bedtime. The patient was then examined to evaluate the Glasgow coma score and the national institutes of health stroke scale (NIHSS).
The summary of the brain CT report provides details the type of stroke, the presence or absence of mass effect, the ischemic territory, the site for intra-cerebral haemorrhages, the presence or absence of ventricular or meningeal haemorrhage, presence or absence of brain herniation and its topography, the volume of the hematoma calculated using the formula developed by Kothari et al. : volume (mm3) = (A * B * C) / 2, where A is the largest diameter in centimetres (cm) of the hematoma on the scan, B is the diameter perpendicular to A and C is the thickness on which the hematoma is visible (number of CT slices x slice thickness). The results of biological workups were noted, e.g.; random or fasting blood sugar, total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol and triglycerides, blood urea level, serum creatinin, full blood count, human immunodeficiency virus infection (HIV) and syphilis serologies, transaminases (aspartate aminotransferase (AST) and alanine aminotransferase (ALT)), ABO and Rhesus blood grouping. We also collected the results of electrocardiogram (presence or absence of atrial fibrillation) and ultrasound of supra-aortic arteries (mostly percentage of arterial stenosis).
The 04 (four) other contacts were on the 14th, 30th, 60th and 90th days after the stroke. Patients or their relatives were contacted by phone to find out if the patient was alive or not. For deceased patients, the day of death was recorded, so as to calculate survival time after stroke.
Data entry and analysis was done using SPSS for windows version 20. Survival probabilities were obtained by the Kaplan Meier method. The difference between survival curves was determined using the Log Rank test. The effect of variables that were significantly associated with prognosis was then studied in multivariate analysis using a Cox proportional hazards model. Data were analysed using SPSS version 20 (SPSS Inc, Chicago, IL). A p value < 0.05 was considered statistically significant.
Ethical considerations: Prior to the start of the study, research authorizations were obtained from the directors of the various hospitals. The research protocol was submitted for approval by the Institutional Ethics and Research Committee of the Faculty of Medicine and Biomedical Sciences of the University of Yaoundé I. Included in the study were patients who freely consented to participate, after explanation of the advantages and disadvantages. For unconscious patients, consent was obtained from family members.