Stroke risk factors, subtypes, and 30-day case fatality in Abuja, Nigeria

Abstract

Background:Stroke is the second leading cause of death and the leading cause of adult disability worldwide. A better understanding of stroke risk factors and outcome may help guide efforts at reducing the community burden of stroke. This study aimed to understand stroke risk factors, imaging subtypes, and 30-day outcomes among adult Nigerians.Materials and Methods:We prospectively recruited all patients presenting with acute stroke at the National Hospital Abuja between January 2010 and June 2012. We assessed clinical and laboratory variables, as well as brain computerized tomography, magnetic resonance imaging, and carotid Doppler ultrasound scans. We also assessed case fatality and functional outcome at 30 days after stroke.Results:Of 272 patients studied, 168 (61.8%) were males. Age at presentation (mean ± standard deviation) was 56.4 ± 12.7 years in males and 52.9 ± 14.8 years in females (P = 0.039). Neuroimaging was obtained in 96.7% patients, revealing cerebral infarction (61.8%), intracerebral hemorrhage (ICH) (34.8%), and subarachnoid hemorrhage (SAH) (3.4%). Carotid plaques or stenosis ≥50% were detected in 53.2% patients with cerebral infarction. Stroke risk factors included hypertension (82.7%), obesity (32.6%), diabetes (23.5%), hyperlipidemia (18.4%), atrial fibrillation (9.2%), and cigarette smoking (7.7%). At 30 days after stroke, case-fatality rate was 18.8%, whereas modified Rankin Scale (mRS) scores for cerebral infarction, ICH, and SAH were 3.71, 4.21, and 4.56, respectively. Atrial fibrillation, a previous stroke, and age older than 50 years were all associated with worse mRS scores at 30 days.Conclusion:Although hypertension, obesity, diabetes mellitus, and atrial fibrillation were important stroke risk factors, in many patients, these were detected only after a stroke. While the commonest stroke subtype was cerebral infarction, observed in almost two-third of patients, SAH was associated with the highest case-fatality rate at 30 days of 44.4%. Larger population-based studies may provide additional data on stroke incidence and outcome among Nigerians.