JNS-13830; No of Pages 5 Journal of the Neurological Sciences xxx (2015) xxx–xxx
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Epidemiology and in-hospital outcome of stroke in South Ethiopia Birrie Deresse a,⁎, Debebe Shaweno b a b
Neurology Unit, Department of Internal Medicine, School of Medicine, College of Medicine and Health Sciences, Hawassa University, Hawassa, Ethiopia School of Public and Environmental Health, College of Medicine and Health Sciences, Hawassa University, Hawassa, Ethiopia
a r t i c l e
i n f o
Article history: Received 5 January 2015 Received in revised form 5 May 2015 Accepted 1 June 2015 Available online xxxx Keywords: Ethiopia Hemorrhagic stroke Ischemic stroke Risk factors Stroke Stroke outcome
a b s t r a c t Introduction: Although the burden of stroke in Sub-Saharan Africa, including Ethiopia, is increasing, there are few available data on stroke in Ethiopia. Objective: To describe the magnitude of risk factors, sub-types and in-hospital outcome of stroke at Hawassa University Referral Hospital, Ethiopia. Methods: A prospective hospital-based study was conducted with all adult patients admitted to Hawassa University Referral Hospital with stroke diagnosis between May 2013 and April 2014. Computerized tomography scan was performed in all patients to confirm the type of stroke. Stroke severity at admission was assessed by the National Institute of Health Stroke Scale. Stroke outcome at discharge was measured using the modified Rankin stroke scale. Results: A total of 163 stroke patients were recruited during the study period, of which 82 (50.3%) patients had ischemic stroke while 81 (49.7%) had hemorrhagic stroke. Stroke risk factors included hypertension (50.9%), cardiac diseases (16.6%), diabetes mellitus (7.4%), alcohol (10.4%), cigarette smoking (4.9%) and tuberculous meningitis (3.1%). In-hospital stroke mortality was 14.7%. The main predictors of in-hospital stroke mortality were stroke severity at admission, hemorrhagic stroke, decreased level of consciousness and seizure. Conclusion: The proportion of hemorrhagic stroke is higher than in Western countries. Hypertension is the most common risk factor for stroke. More than half of the patients were discharged with severe disability. We recommend establishing stroke units in resource limited countries like Ethiopia in order to reduce stroke mortality and post stroke disability. © 2015 Elsevier B.V. All rights reserved.
1. Introduction The updated definition of central nervous system infarction is brain, spinal cord, or retinal cell death attributable to ischemia in a defined vascular territory, based on neuropathological, neuroimaging, and/or clinical evidence of focal ischemic injury with symptoms persisting ≥ 24 h or until death, and other etiologies excluded. Ischemic stroke refers to an episode of neurological dysfunction due to focal cerebral, spinal, or retinal infarction. Stroke caused by intracerebral hemorrhage refers to a rapidly developing clinical signs of neurological dysfunction attributable to a focal collection of blood within the brain parenchyma or ventricular system not due to trauma. Stroke caused by subarachnoid hemorrhage refers to a rapidly developing signs of neurological dysfunction and/or headache because of bleeding into the subarachnoid space, which is not caused by trauma [1]. Stroke is the second leading cause of death [2] and the third leading cause of disability-adjusted life-years worldwide [3]. There were 16.9 million incident strokes, 33.0 million stroke survivors and 5.9 million deaths from stroke
⁎ Corresponding author. E-mail address: [email protected] (B. Deresse).
worldwide in 2010, with most of the burden in low income and middle-income countries. If these trends continue, the overall burden of stroke will double by the year 2030 [4]. According to the World Health Organization, there were 39,409 stroke deaths in Ethiopia in 2004, which accounted for 3.6% of all deaths and 15.3% of deaths from non-communicable diseases [5]. Stroke in Sub-Saharan Africa (SSA) occurs at a relatively young age and the frequency of hemorrhagic stroke is higher than that reported in developed countries [6–10]. Lack of diagnostic neuroimaging limits appropriate documentation of stroke sub-types in resource poor countries. Hypertension is the most important risk factor for stroke in SSA [6,9–14]. Two studies conducted at Addis Ababa, Ethiopia, Tikur Anbessa Teaching Hospital demonstrated that hypertension, cardiac disease and diabetes mellitus occurred in 65.6%, 22.7% and 8.5% of all strokes, respectively [6,15]. A Malawi study reported HIV/AIDS as a major risk factor occurring in 58% of all ischemic strokes [16]. The burden of stroke in SSA, including Ethiopia, is likely to increase because of demographic changes and the inadequate control of major risk factors for stroke including hypertension, cardiac disease, obesity, diabetes, and smoking [17]. However, stroke is largely preventable, so knowledge of stroke risk factors is an essential step in reducing the stroke rate and resulting disease burden.
http://dx.doi.org/10.1016/j.jns.2015.06.001 0022-510X/© 2015 Elsevier B.V. All rights reserved.
Please cite this article as: B. Deresse, D. Shaweno, Epidemiology and in-hospital outcome of stroke in South Ethiopia, J Neurol Sci (2015), http:// dx.doi.org/10.1016/j.jns.2015.06.001
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B. Deresse, D. Shaweno / Journal of the Neurological Sciences xxx (2015) xxx–xxx
Although stroke is becoming a major health problem in low-income and middle income countries, there are few available data on stroke in Ethiopia. And there are no reports from South Ethiopia addressing the demography, risk factors and burden of stroke. The objective of this study is to describe the magnitude of risk factors, sub-types and inhospital outcome of stroke at Hawassa University Referral Hospital, Hawassa, Ethiopia. 2. Materials and methods A prospective hospital-based study was conducted with all adult patients (≥ 15 years) admitted to Hawassa University Referral Hospital with stroke between May 2013 and April 2014. Hawassa is the capital city of South Nations Nationalities and People Regional state. It is 273 km south of Addis Ababa, the capital city of Ethiopia. Hawassa University Referral Hospital (HwURH) provides comprehensive services for a population of 12 million throughout South Ethiopia and neighboring Oromia region. It is the main referral center for neurology patients in Southern Ethiopia. Clinical data were collected using a structured questionnaire which included demographic data; detailed clinical history including onset and duration of symptoms of stroke; risk factors of stroke including hypertension, diabetes mellitus, cardiovascular diseases, dyslipidemia, smoking, excessive alcohol use, previous history of stroke or TIA, HIV infection and other less common factors; detailed clinical and neurological examination; CT scan results and laboratory investigations. Hypertension was ascertained if a patient was taking antihypertensive medication, history of being diagnosed as hypertensive by a health professional prior to stroke, documented blood pressure of ≥ 140/ 90 mm Hg before the stroke or persisting after the acute phase of stroke. Diabetes mellitus was diagnosed if patient was taking antidiabetics drugs prior to stroke, history of being diagnosed as diabetics by a doctor before stroke or if the patient had a documented random blood glucose of greater than 200 mg/dL or fasting blood glucose of greater than 126 mg/dL after the acute phase of stroke. Dyslipidemia was ascertained as per Adult Treatment Panel-III guidelines of the National Cholesterol Education Program [18]. Brain CT scan was performed in all patients to distinguish between ischemic stroke, intracerebral hemorrhage and subarachnoid hemorrhage. Atrial fibrillation was diagnosed on ECG. Echocardiography, carotid Doppler and complete blood count were performed. Other investigations such as cerebrospinal fluid examination were performed if found to be relevant. Stroke severity at admission was assessed by the National Institute of Health Stroke Scale (NIHSS) [19]. Stroke outcome was measured Table 1 Socio demographic characteristics of stroke patients at Hawassa University Referral Hospital. Variables Sex Male Female Age (years) 15–24 25–34 35–44 45–54 55–64 ≥65 Residence (n = 161) Rural Urban Education (n = 156) No education Primary Secondary College and above
Frequency
Percent
108 55
66.3 33.7
6 18 21 34 40 44
3.7 11 12.9 20.9 24.5 27
87 74
54 46
83 34 26 13
53.2 21.8 16.7 8.4
Fig. 1. Anatomic locations of ICH.
using the modified Rankin scale (mRS) at discharge [20,21]. mRS 0–2 was considered mild disability, mRS 3 moderate disability, mRS 4–5 moderately severe to severe disability and mRS 6 dead.
2.1. Statistical analysis Data were analyzed using Statistical Package for the Social Sciences (SPSS) for Windows Version 16. Continuous variables were summarized using measures of central tendency and dispersion and proportions were used for categorical variables. Risk of death was analyzed using RR. Chi-square (χ2) test was used to test the significance of associations between categorical variables. A p value of b0.05 was considered statistically significant.
2.2. Ethical issue The study protocol was approved by the Institutional Review Board (IRB) of the College of Medicine and Health Sciences of Hawassa University. The patients gave consent. In cases of decreased level of consciousness or severe aphasias, the care takers of patients or close relatives gave consent.
Table 2 Magnitude of risk factors of stroke at Hawassa University Referral Hospital. Risk factors
Hypertension Cardiac diseases Diabetes mellitus Atherosclerosis (n = 34) Cigarette smoking Current alcohol Previous history of alcohol intake Previous stroke Transient ischemic attack Dyslipidemia (n = 78) Family history TB meningitis HIV (n = 106) Obesity
Total (n = 163)
Ischemic stroke (n = 82)
Hemorrhagic stroke (n = 81)
n (%)
n (%)
n (%)
83 (50.9) 27 (16.6) 12 (7.4) 13 (38.2) 8 (4.9) 17 (10.4) 12 (7.4)
29 (35.4) 26 (31.7) 7 (8.5) 13 (38.2) 6 (7.3) 6 (7.3) 9 (10.8)
54 (66.7) 1 (1.2) 5 (6.2) 0 (0.0) 2 (2.5) 11 (13.6) 3 (3.7)
4 (2.5) 4 (2.5) 30 (38.5) 2 (1.2) 5 (3.1) 2 (1.9) 3 (1.8)
4 (4.9) 4 (4.9) 19 (35.8) 2 (2.4) 5 (6.1) 2 (2.4) 2 (2.4)
0 (0.0) 0 (0.0) 11 (44) 0 (0.0) 0 (0.0) 0 (0.0) 1 (1.2)
Some patients had multiple risk factors.
Please cite this article as: B. Deresse, D. Shaweno, Epidemiology and in-hospital outcome of stroke in South Ethiopia, J Neurol Sci (2015), http:// dx.doi.org/10.1016/j.jns.2015.06.001
B. Deresse, D. Shaweno / Journal of the Neurological Sciences xxx (2015) xxx–xxx
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Fig. 2. Cardiac diseases among ischemic stroke patients at Hawassa University Referral Hospital.
3. Results There were 7890 total hospital and 1471 medical admissions during the study period. There were a total of 201 stroke admissions, which accounted for 2.5% of total hospital admissions and 13.7% of all medical admissions. Final analysis was done on 163 of 201 stroke patients with complete data. On the remaining 38 cases, data were obtained only on stroke types; 21 (55.3%) ischemic and 17 (44.7%) hemorrhagic, and outcome (7 in-hospital deaths). One hundred and sixty three patients (108 males; 66.3%) with stroke having a mean age of 53.1 ± 16.9 years (range, 16–90 years) at presentation were recruited (Table 1). Of these, 52 (31.9%) patients were admitted directly and 111 (68.1%) were referred from other health facilities. The major ethnic groups were Oromo 51 (32.3%), Sidama 41 (25.9%), Amhara 18 (11.4%), Wolaita 10 (6.3%), Gurage 9 (5.7%) and others 29 (18.4%). Most stroke patients (69%) were admitted more than 24 h after stroke onset. Brain CT scans were done in all 163 patients. Out of the total, 82 (50.3%) patients had ischemic stroke while 81 (49.7%) had hemorrhagic stroke; with intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH) accounting for 43.6% and 6.1% respectively. Three of the ten patients (30%) with SAH had normal brain CT scan and diagnosis was made with history of sudden onset of headache and lumbar puncture showing xanthochromic cerebrospinal fluid (CSF). In patients with ICH, basal ganglia was the most common site (38%), followed by thalamus (29. 6%) and lobar hemorrhage (18.3%) (Fig. 1).
Table 4 Echocardiography findings by stroke type.
Table 3 Electrocardiography (ECG) findings by stroke type. ECG findings (n = 108)
Atrial fibrillation Ischemic heart disease Left ventricular hypertrophy Sinus tachycardia Sinus bradycardia Normal Others
Ischemic stroke (n = 82)
Hemorrhagic stroke (n = 26)
Total (n = 108)
n (%)
n (%)
n (%)
12 (14.6) 4 (4.9) 11 (13.4)
0 0 9 (34.6)
12 (11.1) 4 (3.7) 20 (18.5)
2 (2.4) 4 (4.9) 42 (51.2) 8 (9.8)
2 (7.7) 0 14 (53.8) 1 (3.8)
4 (3.7) 4 (3.7) 56 (51.9) 9 (8.3)
Some patients had multiple ECG findings.
Patients with ischemic stroke were classified according to the Oxfordshire Community Stroke Project (OCSP) classification [22]. Of 82 patients with ischemic stroke, 14 (17.1%) had total anterior circulation infarct (TACI), 49 (59.8%) had partial anterior circulation infarct (PACI), 17 (20.7%) had lacunar infarct (LACI), and 2 (2.4%) had posterior circulation infarct (POCI). Based on CT scan findings of 82 ischemic stroke cases, 53 (64.6%) had cortical infarction, 19 (23.2%) subcortical infarction, 1 (1.2%) brainstem infarction, 1 (1.2%) cerebellar infarction, 7 (8.5%) multifocal infarction and 1 (1.2%) had normal CT scan. Hypertension was the main risk factor for ischemic and hemorrhagic strokes, occurring in 50.9% of all strokes. Other risk factors included cardiac diseases (16.6%), diabetes mellitus (7.4%), alcohol (10.4%), and cigarette smoking (4.9%) (Table 2). Hypertension was significantly higher among hemorrhagic stroke patients (p b 0.001) but cardiac diseases were significantly higher among ischemic stroke patients (p b 0.001). Of 82 patients with ischemic stroke, 26 (31.7%) had cardioembolic stroke. Atrial fibrillation was the most common cardiac source of embolism in ischemic stroke (12, 14.6%) (Fig. 2). Out of 163 patients, 108 (66.3%) and 86 (52.8%) had electrocardiography and echocardiography study done respectively (Tables 3 & 4). Thirty four of all ischemic stroke patients (41.5%) had bilateral carotid Doppler study done. Of these 34 patients 20 (58.8%) had normal bilateral carotid Doppler study findings; 10 (29.4%) had carotid atherosclerotic plaques without stenosis; 3 (8.8%) had carotid atherosclerosis and thrombus with stenosis/occlusion, and 1 (2.9%) had right common carotid artery aneurysm.
Echocardiography findings (n = 86)
Left ventricular hypertrophy Rheumatic valvular heart disease Dilated cardiomyopathy Restrictive cardiomyopathy Ischemic cardiomyopathy Ischemic heart disease with mural thrombus/LV apical thrombus Left atrial myxoma Normal Others
Ischemic stroke (n = 62)
Hemorrhagic stroke (n = 24)
Total (n = 86)
n (%)
n (%)
n (%)
25 (40.3) 7 (11.3) 5 (8.1) 1 (1.6) 1 (1.6) 2 (3.2)
14 (58.3) 1 (4.2) 0 0 0 0
39 (45.3) 8 (9.3) 5 (5.8) 1 (1.2) 1 (1.2) 2 (2.3)
1 (1.6) 17 (27.4) 3 (4.8)
0 6 (25.0) 3 (12.5)
1 (1.2) 23 (26.7) 6 (7.0)
Please cite this article as: B. Deresse, D. Shaweno, Epidemiology and in-hospital outcome of stroke in South Ethiopia, J Neurol Sci (2015), http:// dx.doi.org/10.1016/j.jns.2015.06.001
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B. Deresse, D. Shaweno / Journal of the Neurological Sciences xxx (2015) xxx–xxx
Table 5 Severity and outcome by stroke types at Hawassa University Referral Hospital. Characteristics Stroke severity (NIHSS) (n = 157) NIHSS 0–6 (mild) NIHSS 7–12 (moderate) NIHSS 13–20 (severe) NIHSS ≥ 21 (very severe) Stroke outcome (mRS) mRS 0–2 (mild disability) mRS 3 (moderate disability) mRS 4–5 (severe disability) mRS 6 (death)
Ischemic stroke (n =82)
Hemorrhagic stroke (n = 81)
Total (n = 163)
17 (21.8%) 34 (43.6%) 22 (28.2%) 5 (6.4%)
21 (26.6%) 20 (25.3%) 24 (30.4%) 14 (17.7%)
38 (24.2%) 54 (34.4%) 46 (29.3%) 19 (12.1%)
15 (18.3%) 8 (9.8%) 54 (65.9%) 5 (6.1%)
17 (21.0%) 9 (11.1%) 36 (44.4%) 19 (23.5%)
32 (19.6%) 17 (10.4%) 90 (55.2%) 24 (14.7%)
3.1. Severity and outcome of stroke Sixty-five patients (41.4%) had severe strokes (NIHSS ≥ 13) on admission. The median NIHSS was 10 [interquartile range (IQR) 7 to15] for ischemic stroke and 12 (IQR 6 to19) for hemorrhagic stroke. At discharge 32 (19.6%) had mRS 0–2, 17 (10.4%) had mRS 3 and 90 (55.2%) had mRS 4–5 (Table 5). The median length of hospital stay was 9 days (IQR 6 to 14 days). Overall, twenty-four (14.7%) died in hospital. Death occurred at a median of 4.5 days (IQR 2 to 7 days) after admission. The in-hospital stroke mortality was higher for hemorrhagic stroke (23.5%) compared to ischemic stroke (6.1%). Immediate causes of death included increased intracranial pressure in 18/24 (75%), aspiration pneumonia and/or Hospital acquired pneumonia in 5/24 (20.8%) and refractory status epilepticus in 1/24 (4.2%). NIHSS ≥ 13 at admission was associated with increased risk of inhospital stroke mortality (RR 11.7; 95% CI, 1.63–83.7). The risk of dying after hemorrhagic stroke was about four times higher than after ischemic stroke (RR 3.85; 95% CI, 1.51–9.81). Decreased level of consciousness (RR 3.8; 95% CI, 3.8–39.6) and seizure (RR 3.7; 95% CI, 1.53–9.14) at presentation were also associated with increased risk of stroke mortality. Stroke mortality risk was not different by age and sex (Table 6).
4. Discussion We performed a prospective hospital-based study to determine stroke sub-types, risk factors and in-hospital mortality in a resource limited setting where there are neither stroke units nor comprehensive rehabilitation centers. There was male preponderance (66.3%) with M:F ratio of 2:1. This is similar to other studies [6,23–25]. The mean age of patients at presentation was 53.1 ± 16.9 years. This is similar to other studies among African population [6,9–11,26,27]. The average age of our patients was Table 6 Predictors of stroke death among stroke patients at Hawassa University Referral Hospital. Predictors
Sex Decreased level of consciousness Seizure NIHSS
Time from onset of stroke to admission Stroke types
Patient condition at discharge
Male Female Yes No Yes No NIHSS 0– 6 NIHSS 7–12 NIHSS ≥ 13 Within 24 h After 24 h Hemorrhagic Ischemic
Died
Alive
17 7 21 3 3 21 1 2 20 10 14 19 5
91 48 38 101 3 136 37 52 45 40 98 62 77
RR (95% CI)
1.2 (0.55, 2.8) 1.0 12.3 (3.8, 39.6) 1.0 3.7 (1.53, 9.14) 1.0 1.0 1.4 (0.13, 15.0) 11.7 (1.63, 83.7) 1.6 (0.76, 3.35) 1.0 3.85 (1.51, 9.81) 1.0
younger than stroke patients in Western countries. The European Registers of Stroke reported median age of 73 years (IQR 62 to 81) [28]. Our study revealed that ischemic stroke (50.3%) and hemorrhagic stroke (49.7%) occurred in almost equal proportion in our patients. A higher percentage of hemorrhagic strokes (59.2%) had been reported in a study at Tikur Anbessa Teaching Hospital, Addis Ababa, Ethiopia [6]. However, the proportion of hemorrhagic stroke in our study and other hospital based studies in SSA is higher than that reported in Western countries [6–8,10,29]. This difference could be related to differences in study setting and poor control of hypertension in SSA including Ethiopia. Hypertension was the most common risk factor for all strokes, being present in half of our patients. This is consistent with findings from both low income and high income countries [6,9–14,23,24,26]. It has been shown that lowering blood pressure can reduce the risk of stroke by 30 to 40% [30,31]. Thus, detection and treatment of hypertension remain the most important strategies in the prevention of stroke. Cardiac diseases were important risk factors for ischemic stroke in our study. Atrial fibrillation was the most common cardiac source of embolism occurring in 14.6% of ischemic stroke patients. In the INTERSTROKE study, atrial fibrillation was the most common cardiac source of thromboembolism in patients with ischemic stroke, with regional variation in prevalence; 23% in high-income countries, 13% in South America, 7% in Africa, 6% in India, and 5% in Southeast Asia [14]. Rheumatic heart disease (RHD) was found in 8.5% of our patients with ischemic stroke. It is estimated that 3–7.5% of all strokes in less developed countries are related to RHD [32]. The proportion of RHD in ischemic stroke patients ranges from 3.4% to 23.2% in Asia and 1.8% to 2.0% in Europe and Northern America [33]. Although RHD is common in SSA countries, little information is available on the risk of stroke associated with RHD in Africa. Our study showed that RHD is an important cause of ischemic stroke in low-income countries like Ethiopia. The frequency of diabetes in our ischemic stroke patients was lower than that reported in the INTERSTROKE study, in which diabetes was prevalent among 21% of patients with ischemic stroke [14]. This discrepancy could be explained by our small sample size and single hospital-based design of the study. We recommend well designed multi-centered studies to quantify the risk of stroke in Ethiopian diabetic patients. Alcohol use among our stroke patients was less frequently (10.4%) reported than in other African studies [10,27] and the INTERSTROKE study) [14]. It is worth noting that 5 of the 82 patients with ischemic stroke (6.1%) in our study had tuberculous meningitis. Other studies have reported that stroke occurred in about 15–57% of patients with tuberculous meningitis [34]. Thus, neuro-infections like meningitis should be considered as a potential risk factor for stroke, especially in lowincome countries where infectious diseases are still common. The overall in-hospital stroke mortality in this study is higher than that of high income countries [35,36] but lower than that reported from SSA. In-hospital stroke mortality of 19.8% to 44% had been reported in other African hospital based studies [6,10,24,27]. The main predictors
Please cite this article as: B. Deresse, D. Shaweno, Epidemiology and in-hospital outcome of stroke in South Ethiopia, J Neurol Sci (2015), http:// dx.doi.org/10.1016/j.jns.2015.06.001
B. Deresse, D. Shaweno / Journal of the Neurological Sciences xxx (2015) xxx–xxx
of in-hospital stroke mortality in our study were stroke severity (NIHSS ≥ 13) at admission, the type of stroke (hemorrhagic stroke), decreased level of consciousness and seizure. Regarding post stroke disability, more than half of our patients were discharged with severe disability. This reflects limited rehabilitation services in our hospital which is the case for most low income countries. Studies have shown that stroke patients who are managed in stroke units have reduced risk of both in-hospital mortality and dependency [37–39]. This study is limited due to the fact it was entirely hospital-based, thereby excluding outpatient stroke events. Stroke patients with mild symptoms might not come to hospital and patients with very severe stroke may die before they reach to hospital. Thus, stroke mortality may be underestimated in our study. 5. Conclusion Ethiopian patients suffer stroke at a relatively young age, and the proportion of hemorrhagic stroke is higher than in Western countries. Hypertension is the most common risk factor for both ischemic and hemorrhagic strokes. In-hospital stroke mortality in our population exceeds that of high income countries. More than half of the patients were discharged with severe disability. Creation of public awareness on stroke risk factors remains the most important measure to reduce stroke burden. Establishing stroke units in Ethiopia is important in order to reduce stroke mortality and post stroke disability. Acknowledgments We would like to thank Hawassa University for funding this research. We are grateful to all patients and their families who took part in this study. The authors are also grateful to Professor James C. Johnston for reviewing the manuscript. Source of funding: Hawassa University Conflict of interest: none. References [1] R.L. Sacco, S.E. Kasner, J.P. Broderick, L.R. Caplan, J.J. Connors, A. Culebras, et al., An updated definition of stroke for the 21st century: a statement for healthcare professionals from the American Heart Association/American Stroke Association, Stroke 44 (2013) 2064–2089. [2] R. Lozano, M. Naghavi, K. Foreman, S. Lim, K. Shibuya, V. Aboyans, et al., Global and regional mortality from 235 causes of death for 20 age groups in 1990 and 2010: a systematic analysis for the Global Burden of Disease Study 2010, Lancet 380 (2012) 2095–2128. [3] C.J.L. Murray, T. Vos, R. Lozano, M. Naghavi, A.D. Flaxman, C. Michaud, et al., Disability-adjusted life-years for 291 diseases and injuries in 21 regions, 1990–2010: a systematic analysis for the Global Burden of Disease Study 2010, Lancet 380 (2012) 2197–2223. [4] V.L. Feigin, M.H. Forouzanfar, R. Krishnamurthi, G.A. Mensah, M. Connor, D.A. Bennett, et al., Global and regional burden of stroke during 1990–2010: findings from the Global Burden of Disease Study 2010, Lancet 383 (2014) 245–254. [5] WHO, WHO Global InfoBase, https://apps.who.int/infobase/Mortality.aspx2011 (Accessed 19 Sep. 2012). [6] G. Zeneb, M. Alemayehu, J. Asmera, Characteristics and outcomes of stroke at Tikur Anbessa Teaching Hospital, Ethiopia, Ethiop. Med. J. 43 (2005) 251–259. [7] P.K. Nyame, K.B. Jumah, S. Adjei, Computerized tomographic scan of the head in evaluation of stroke in Ghanaians, East Afr. Med. J. 75 (1998) 637–639. [8] W. Matuja, M. Janabi, R. Kazema, D. Mashuke, Stroke subtypes in black Tanzanians: a retrospective study of computerized tomography scan diagnoses at Muhimbili National Hospital, Dar es Salaam, Trop. Dr. 34 (2004) 144–146. [9] J. Matenga, I. Kitai, L. Levy, Strokes among black people in Harare, Zimbabwe: results of computed tomography and associated risk factors, BMJ 292 (1986) 1649–1651.
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Epidemiology and in-hospital outcome of stroke in South Ethiopia Birrie Deresse a,⁎, Debebe Shaweno b a b
Neurology Unit, Department of Internal Medicine, School of Medicine, College of Medicine and Health Sciences, Hawassa University, Hawassa, Ethiopia School of Public and Environmental Health, College of Medicine and Health Sciences, Hawassa University, Hawassa, Ethiopia
a r t i c l e
i n f o
Article history: Received 5 January 2015 Received in revised form 5 May 2015 Accepted 1 June 2015 Available online xxxx Keywords: Ethiopia Hemorrhagic stroke Ischemic stroke Risk factors Stroke Stroke outcome
a b s t r a c t Introduction: Although the burden of stroke in Sub-Saharan Africa, including Ethiopia, is increasing, there are few available data on stroke in Ethiopia. Objective: To describe the magnitude of risk factors, sub-types and in-hospital outcome of stroke at Hawassa University Referral Hospital, Ethiopia. Methods: A prospective hospital-based study was conducted with all adult patients admitted to Hawassa University Referral Hospital with stroke diagnosis between May 2013 and April 2014. Computerized tomography scan was performed in all patients to confirm the type of stroke. Stroke severity at admission was assessed by the National Institute of Health Stroke Scale. Stroke outcome at discharge was measured using the modified Rankin stroke scale. Results: A total of 163 stroke patients were recruited during the study period, of which 82 (50.3%) patients had ischemic stroke while 81 (49.7%) had hemorrhagic stroke. Stroke risk factors included hypertension (50.9%), cardiac diseases (16.6%), diabetes mellitus (7.4%), alcohol (10.4%), cigarette smoking (4.9%) and tuberculous meningitis (3.1%). In-hospital stroke mortality was 14.7%. The main predictors of in-hospital stroke mortality were stroke severity at admission, hemorrhagic stroke, decreased level of consciousness and seizure. Conclusion: The proportion of hemorrhagic stroke is higher than in Western countries. Hypertension is the most common risk factor for stroke. More than half of the patients were discharged with severe disability. We recommend establishing stroke units in resource limited countries like Ethiopia in order to reduce stroke mortality and post stroke disability. © 2015 Elsevier B.V. All rights reserved.
1. Introduction The updated definition of central nervous system infarction is brain, spinal cord, or retinal cell death attributable to ischemia in a defined vascular territory, based on neuropathological, neuroimaging, and/or clinical evidence of focal ischemic injury with symptoms persisting ≥ 24 h or until death, and other etiologies excluded. Ischemic stroke refers to an episode of neurological dysfunction due to focal cerebral, spinal, or retinal infarction. Stroke caused by intracerebral hemorrhage refers to a rapidly developing clinical signs of neurological dysfunction attributable to a focal collection of blood within the brain parenchyma or ventricular system not due to trauma. Stroke caused by subarachnoid hemorrhage refers to a rapidly developing signs of neurological dysfunction and/or headache because of bleeding into the subarachnoid space, which is not caused by trauma [1]. Stroke is the second leading cause of death [2] and the third leading cause of disability-adjusted life-years worldwide [3]. There were 16.9 million incident strokes, 33.0 million stroke survivors and 5.9 million deaths from stroke
⁎ Corresponding author. E-mail address: [email protected] (B. Deresse).
worldwide in 2010, with most of the burden in low income and middle-income countries. If these trends continue, the overall burden of stroke will double by the year 2030 [4]. According to the World Health Organization, there were 39,409 stroke deaths in Ethiopia in 2004, which accounted for 3.6% of all deaths and 15.3% of deaths from non-communicable diseases [5]. Stroke in Sub-Saharan Africa (SSA) occurs at a relatively young age and the frequency of hemorrhagic stroke is higher than that reported in developed countries [6–10]. Lack of diagnostic neuroimaging limits appropriate documentation of stroke sub-types in resource poor countries. Hypertension is the most important risk factor for stroke in SSA [6,9–14]. Two studies conducted at Addis Ababa, Ethiopia, Tikur Anbessa Teaching Hospital demonstrated that hypertension, cardiac disease and diabetes mellitus occurred in 65.6%, 22.7% and 8.5% of all strokes, respectively [6,15]. A Malawi study reported HIV/AIDS as a major risk factor occurring in 58% of all ischemic strokes [16]. The burden of stroke in SSA, including Ethiopia, is likely to increase because of demographic changes and the inadequate control of major risk factors for stroke including hypertension, cardiac disease, obesity, diabetes, and smoking [17]. However, stroke is largely preventable, so knowledge of stroke risk factors is an essential step in reducing the stroke rate and resulting disease burden.
http://dx.doi.org/10.1016/j.jns.2015.06.001 0022-510X/© 2015 Elsevier B.V. All rights reserved.
Please cite this article as: B. Deresse, D. Shaweno, Epidemiology and in-hospital outcome of stroke in South Ethiopia, J Neurol Sci (2015), http:// dx.doi.org/10.1016/j.jns.2015.06.001
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B. Deresse, D. Shaweno / Journal of the Neurological Sciences xxx (2015) xxx–xxx
Although stroke is becoming a major health problem in low-income and middle income countries, there are few available data on stroke in Ethiopia. And there are no reports from South Ethiopia addressing the demography, risk factors and burden of stroke. The objective of this study is to describe the magnitude of risk factors, sub-types and inhospital outcome of stroke at Hawassa University Referral Hospital, Hawassa, Ethiopia. 2. Materials and methods A prospective hospital-based study was conducted with all adult patients (≥ 15 years) admitted to Hawassa University Referral Hospital with stroke between May 2013 and April 2014. Hawassa is the capital city of South Nations Nationalities and People Regional state. It is 273 km south of Addis Ababa, the capital city of Ethiopia. Hawassa University Referral Hospital (HwURH) provides comprehensive services for a population of 12 million throughout South Ethiopia and neighboring Oromia region. It is the main referral center for neurology patients in Southern Ethiopia. Clinical data were collected using a structured questionnaire which included demographic data; detailed clinical history including onset and duration of symptoms of stroke; risk factors of stroke including hypertension, diabetes mellitus, cardiovascular diseases, dyslipidemia, smoking, excessive alcohol use, previous history of stroke or TIA, HIV infection and other less common factors; detailed clinical and neurological examination; CT scan results and laboratory investigations. Hypertension was ascertained if a patient was taking antihypertensive medication, history of being diagnosed as hypertensive by a health professional prior to stroke, documented blood pressure of ≥ 140/ 90 mm Hg before the stroke or persisting after the acute phase of stroke. Diabetes mellitus was diagnosed if patient was taking antidiabetics drugs prior to stroke, history of being diagnosed as diabetics by a doctor before stroke or if the patient had a documented random blood glucose of greater than 200 mg/dL or fasting blood glucose of greater than 126 mg/dL after the acute phase of stroke. Dyslipidemia was ascertained as per Adult Treatment Panel-III guidelines of the National Cholesterol Education Program [18]. Brain CT scan was performed in all patients to distinguish between ischemic stroke, intracerebral hemorrhage and subarachnoid hemorrhage. Atrial fibrillation was diagnosed on ECG. Echocardiography, carotid Doppler and complete blood count were performed. Other investigations such as cerebrospinal fluid examination were performed if found to be relevant. Stroke severity at admission was assessed by the National Institute of Health Stroke Scale (NIHSS) [19]. Stroke outcome was measured Table 1 Socio demographic characteristics of stroke patients at Hawassa University Referral Hospital. Variables Sex Male Female Age (years) 15–24 25–34 35–44 45–54 55–64 ≥65 Residence (n = 161) Rural Urban Education (n = 156) No education Primary Secondary College and above
Frequency
Percent
108 55
66.3 33.7
6 18 21 34 40 44
3.7 11 12.9 20.9 24.5 27
87 74
54 46
83 34 26 13
53.2 21.8 16.7 8.4
Fig. 1. Anatomic locations of ICH.
using the modified Rankin scale (mRS) at discharge [20,21]. mRS 0–2 was considered mild disability, mRS 3 moderate disability, mRS 4–5 moderately severe to severe disability and mRS 6 dead.
2.1. Statistical analysis Data were analyzed using Statistical Package for the Social Sciences (SPSS) for Windows Version 16. Continuous variables were summarized using measures of central tendency and dispersion and proportions were used for categorical variables. Risk of death was analyzed using RR. Chi-square (χ2) test was used to test the significance of associations between categorical variables. A p value of b0.05 was considered statistically significant.
2.2. Ethical issue The study protocol was approved by the Institutional Review Board (IRB) of the College of Medicine and Health Sciences of Hawassa University. The patients gave consent. In cases of decreased level of consciousness or severe aphasias, the care takers of patients or close relatives gave consent.
Table 2 Magnitude of risk factors of stroke at Hawassa University Referral Hospital. Risk factors
Hypertension Cardiac diseases Diabetes mellitus Atherosclerosis (n = 34) Cigarette smoking Current alcohol Previous history of alcohol intake Previous stroke Transient ischemic attack Dyslipidemia (n = 78) Family history TB meningitis HIV (n = 106) Obesity
Total (n = 163)
Ischemic stroke (n = 82)
Hemorrhagic stroke (n = 81)
n (%)
n (%)
n (%)
83 (50.9) 27 (16.6) 12 (7.4) 13 (38.2) 8 (4.9) 17 (10.4) 12 (7.4)
29 (35.4) 26 (31.7) 7 (8.5) 13 (38.2) 6 (7.3) 6 (7.3) 9 (10.8)
54 (66.7) 1 (1.2) 5 (6.2) 0 (0.0) 2 (2.5) 11 (13.6) 3 (3.7)
4 (2.5) 4 (2.5) 30 (38.5) 2 (1.2) 5 (3.1) 2 (1.9) 3 (1.8)
4 (4.9) 4 (4.9) 19 (35.8) 2 (2.4) 5 (6.1) 2 (2.4) 2 (2.4)
0 (0.0) 0 (0.0) 11 (44) 0 (0.0) 0 (0.0) 0 (0.0) 1 (1.2)
Some patients had multiple risk factors.
Please cite this article as: B. Deresse, D. Shaweno, Epidemiology and in-hospital outcome of stroke in South Ethiopia, J Neurol Sci (2015), http:// dx.doi.org/10.1016/j.jns.2015.06.001
B. Deresse, D. Shaweno / Journal of the Neurological Sciences xxx (2015) xxx–xxx
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Fig. 2. Cardiac diseases among ischemic stroke patients at Hawassa University Referral Hospital.
3. Results There were 7890 total hospital and 1471 medical admissions during the study period. There were a total of 201 stroke admissions, which accounted for 2.5% of total hospital admissions and 13.7% of all medical admissions. Final analysis was done on 163 of 201 stroke patients with complete data. On the remaining 38 cases, data were obtained only on stroke types; 21 (55.3%) ischemic and 17 (44.7%) hemorrhagic, and outcome (7 in-hospital deaths). One hundred and sixty three patients (108 males; 66.3%) with stroke having a mean age of 53.1 ± 16.9 years (range, 16–90 years) at presentation were recruited (Table 1). Of these, 52 (31.9%) patients were admitted directly and 111 (68.1%) were referred from other health facilities. The major ethnic groups were Oromo 51 (32.3%), Sidama 41 (25.9%), Amhara 18 (11.4%), Wolaita 10 (6.3%), Gurage 9 (5.7%) and others 29 (18.4%). Most stroke patients (69%) were admitted more than 24 h after stroke onset. Brain CT scans were done in all 163 patients. Out of the total, 82 (50.3%) patients had ischemic stroke while 81 (49.7%) had hemorrhagic stroke; with intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH) accounting for 43.6% and 6.1% respectively. Three of the ten patients (30%) with SAH had normal brain CT scan and diagnosis was made with history of sudden onset of headache and lumbar puncture showing xanthochromic cerebrospinal fluid (CSF). In patients with ICH, basal ganglia was the most common site (38%), followed by thalamus (29. 6%) and lobar hemorrhage (18.3%) (Fig. 1).
Table 4 Echocardiography findings by stroke type.
Table 3 Electrocardiography (ECG) findings by stroke type. ECG findings (n = 108)
Atrial fibrillation Ischemic heart disease Left ventricular hypertrophy Sinus tachycardia Sinus bradycardia Normal Others
Ischemic stroke (n = 82)
Hemorrhagic stroke (n = 26)
Total (n = 108)
n (%)
n (%)
n (%)
12 (14.6) 4 (4.9) 11 (13.4)
0 0 9 (34.6)
12 (11.1) 4 (3.7) 20 (18.5)
2 (2.4) 4 (4.9) 42 (51.2) 8 (9.8)
2 (7.7) 0 14 (53.8) 1 (3.8)
4 (3.7) 4 (3.7) 56 (51.9) 9 (8.3)
Some patients had multiple ECG findings.
Patients with ischemic stroke were classified according to the Oxfordshire Community Stroke Project (OCSP) classification [22]. Of 82 patients with ischemic stroke, 14 (17.1%) had total anterior circulation infarct (TACI), 49 (59.8%) had partial anterior circulation infarct (PACI), 17 (20.7%) had lacunar infarct (LACI), and 2 (2.4%) had posterior circulation infarct (POCI). Based on CT scan findings of 82 ischemic stroke cases, 53 (64.6%) had cortical infarction, 19 (23.2%) subcortical infarction, 1 (1.2%) brainstem infarction, 1 (1.2%) cerebellar infarction, 7 (8.5%) multifocal infarction and 1 (1.2%) had normal CT scan. Hypertension was the main risk factor for ischemic and hemorrhagic strokes, occurring in 50.9% of all strokes. Other risk factors included cardiac diseases (16.6%), diabetes mellitus (7.4%), alcohol (10.4%), and cigarette smoking (4.9%) (Table 2). Hypertension was significantly higher among hemorrhagic stroke patients (p b 0.001) but cardiac diseases were significantly higher among ischemic stroke patients (p b 0.001). Of 82 patients with ischemic stroke, 26 (31.7%) had cardioembolic stroke. Atrial fibrillation was the most common cardiac source of embolism in ischemic stroke (12, 14.6%) (Fig. 2). Out of 163 patients, 108 (66.3%) and 86 (52.8%) had electrocardiography and echocardiography study done respectively (Tables 3 & 4). Thirty four of all ischemic stroke patients (41.5%) had bilateral carotid Doppler study done. Of these 34 patients 20 (58.8%) had normal bilateral carotid Doppler study findings; 10 (29.4%) had carotid atherosclerotic plaques without stenosis; 3 (8.8%) had carotid atherosclerosis and thrombus with stenosis/occlusion, and 1 (2.9%) had right common carotid artery aneurysm.
Echocardiography findings (n = 86)
Left ventricular hypertrophy Rheumatic valvular heart disease Dilated cardiomyopathy Restrictive cardiomyopathy Ischemic cardiomyopathy Ischemic heart disease with mural thrombus/LV apical thrombus Left atrial myxoma Normal Others
Ischemic stroke (n = 62)
Hemorrhagic stroke (n = 24)
Total (n = 86)
n (%)
n (%)
n (%)
25 (40.3) 7 (11.3) 5 (8.1) 1 (1.6) 1 (1.6) 2 (3.2)
14 (58.3) 1 (4.2) 0 0 0 0
39 (45.3) 8 (9.3) 5 (5.8) 1 (1.2) 1 (1.2) 2 (2.3)
1 (1.6) 17 (27.4) 3 (4.8)
0 6 (25.0) 3 (12.5)
1 (1.2) 23 (26.7) 6 (7.0)
Please cite this article as: B. Deresse, D. Shaweno, Epidemiology and in-hospital outcome of stroke in South Ethiopia, J Neurol Sci (2015), http:// dx.doi.org/10.1016/j.jns.2015.06.001
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B. Deresse, D. Shaweno / Journal of the Neurological Sciences xxx (2015) xxx–xxx
Table 5 Severity and outcome by stroke types at Hawassa University Referral Hospital. Characteristics Stroke severity (NIHSS) (n = 157) NIHSS 0–6 (mild) NIHSS 7–12 (moderate) NIHSS 13–20 (severe) NIHSS ≥ 21 (very severe) Stroke outcome (mRS) mRS 0–2 (mild disability) mRS 3 (moderate disability) mRS 4–5 (severe disability) mRS 6 (death)
Ischemic stroke (n =82)
Hemorrhagic stroke (n = 81)
Total (n = 163)
17 (21.8%) 34 (43.6%) 22 (28.2%) 5 (6.4%)
21 (26.6%) 20 (25.3%) 24 (30.4%) 14 (17.7%)
38 (24.2%) 54 (34.4%) 46 (29.3%) 19 (12.1%)
15 (18.3%) 8 (9.8%) 54 (65.9%) 5 (6.1%)
17 (21.0%) 9 (11.1%) 36 (44.4%) 19 (23.5%)
32 (19.6%) 17 (10.4%) 90 (55.2%) 24 (14.7%)
3.1. Severity and outcome of stroke Sixty-five patients (41.4%) had severe strokes (NIHSS ≥ 13) on admission. The median NIHSS was 10 [interquartile range (IQR) 7 to15] for ischemic stroke and 12 (IQR 6 to19) for hemorrhagic stroke. At discharge 32 (19.6%) had mRS 0–2, 17 (10.4%) had mRS 3 and 90 (55.2%) had mRS 4–5 (Table 5). The median length of hospital stay was 9 days (IQR 6 to 14 days). Overall, twenty-four (14.7%) died in hospital. Death occurred at a median of 4.5 days (IQR 2 to 7 days) after admission. The in-hospital stroke mortality was higher for hemorrhagic stroke (23.5%) compared to ischemic stroke (6.1%). Immediate causes of death included increased intracranial pressure in 18/24 (75%), aspiration pneumonia and/or Hospital acquired pneumonia in 5/24 (20.8%) and refractory status epilepticus in 1/24 (4.2%). NIHSS ≥ 13 at admission was associated with increased risk of inhospital stroke mortality (RR 11.7; 95% CI, 1.63–83.7). The risk of dying after hemorrhagic stroke was about four times higher than after ischemic stroke (RR 3.85; 95% CI, 1.51–9.81). Decreased level of consciousness (RR 3.8; 95% CI, 3.8–39.6) and seizure (RR 3.7; 95% CI, 1.53–9.14) at presentation were also associated with increased risk of stroke mortality. Stroke mortality risk was not different by age and sex (Table 6).
4. Discussion We performed a prospective hospital-based study to determine stroke sub-types, risk factors and in-hospital mortality in a resource limited setting where there are neither stroke units nor comprehensive rehabilitation centers. There was male preponderance (66.3%) with M:F ratio of 2:1. This is similar to other studies [6,23–25]. The mean age of patients at presentation was 53.1 ± 16.9 years. This is similar to other studies among African population [6,9–11,26,27]. The average age of our patients was Table 6 Predictors of stroke death among stroke patients at Hawassa University Referral Hospital. Predictors
Sex Decreased level of consciousness Seizure NIHSS
Time from onset of stroke to admission Stroke types
Patient condition at discharge
Male Female Yes No Yes No NIHSS 0– 6 NIHSS 7–12 NIHSS ≥ 13 Within 24 h After 24 h Hemorrhagic Ischemic
Died
Alive
17 7 21 3 3 21 1 2 20 10 14 19 5
91 48 38 101 3 136 37 52 45 40 98 62 77
RR (95% CI)
1.2 (0.55, 2.8) 1.0 12.3 (3.8, 39.6) 1.0 3.7 (1.53, 9.14) 1.0 1.0 1.4 (0.13, 15.0) 11.7 (1.63, 83.7) 1.6 (0.76, 3.35) 1.0 3.85 (1.51, 9.81) 1.0
younger than stroke patients in Western countries. The European Registers of Stroke reported median age of 73 years (IQR 62 to 81) [28]. Our study revealed that ischemic stroke (50.3%) and hemorrhagic stroke (49.7%) occurred in almost equal proportion in our patients. A higher percentage of hemorrhagic strokes (59.2%) had been reported in a study at Tikur Anbessa Teaching Hospital, Addis Ababa, Ethiopia [6]. However, the proportion of hemorrhagic stroke in our study and other hospital based studies in SSA is higher than that reported in Western countries [6–8,10,29]. This difference could be related to differences in study setting and poor control of hypertension in SSA including Ethiopia. Hypertension was the most common risk factor for all strokes, being present in half of our patients. This is consistent with findings from both low income and high income countries [6,9–14,23,24,26]. It has been shown that lowering blood pressure can reduce the risk of stroke by 30 to 40% [30,31]. Thus, detection and treatment of hypertension remain the most important strategies in the prevention of stroke. Cardiac diseases were important risk factors for ischemic stroke in our study. Atrial fibrillation was the most common cardiac source of embolism occurring in 14.6% of ischemic stroke patients. In the INTERSTROKE study, atrial fibrillation was the most common cardiac source of thromboembolism in patients with ischemic stroke, with regional variation in prevalence; 23% in high-income countries, 13% in South America, 7% in Africa, 6% in India, and 5% in Southeast Asia [14]. Rheumatic heart disease (RHD) was found in 8.5% of our patients with ischemic stroke. It is estimated that 3–7.5% of all strokes in less developed countries are related to RHD [32]. The proportion of RHD in ischemic stroke patients ranges from 3.4% to 23.2% in Asia and 1.8% to 2.0% in Europe and Northern America [33]. Although RHD is common in SSA countries, little information is available on the risk of stroke associated with RHD in Africa. Our study showed that RHD is an important cause of ischemic stroke in low-income countries like Ethiopia. The frequency of diabetes in our ischemic stroke patients was lower than that reported in the INTERSTROKE study, in which diabetes was prevalent among 21% of patients with ischemic stroke [14]. This discrepancy could be explained by our small sample size and single hospital-based design of the study. We recommend well designed multi-centered studies to quantify the risk of stroke in Ethiopian diabetic patients. Alcohol use among our stroke patients was less frequently (10.4%) reported than in other African studies [10,27] and the INTERSTROKE study) [14]. It is worth noting that 5 of the 82 patients with ischemic stroke (6.1%) in our study had tuberculous meningitis. Other studies have reported that stroke occurred in about 15–57% of patients with tuberculous meningitis [34]. Thus, neuro-infections like meningitis should be considered as a potential risk factor for stroke, especially in lowincome countries where infectious diseases are still common. The overall in-hospital stroke mortality in this study is higher than that of high income countries [35,36] but lower than that reported from SSA. In-hospital stroke mortality of 19.8% to 44% had been reported in other African hospital based studies [6,10,24,27]. The main predictors
Please cite this article as: B. Deresse, D. Shaweno, Epidemiology and in-hospital outcome of stroke in South Ethiopia, J Neurol Sci (2015), http:// dx.doi.org/10.1016/j.jns.2015.06.001
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of in-hospital stroke mortality in our study were stroke severity (NIHSS ≥ 13) at admission, the type of stroke (hemorrhagic stroke), decreased level of consciousness and seizure. Regarding post stroke disability, more than half of our patients were discharged with severe disability. This reflects limited rehabilitation services in our hospital which is the case for most low income countries. Studies have shown that stroke patients who are managed in stroke units have reduced risk of both in-hospital mortality and dependency [37–39]. This study is limited due to the fact it was entirely hospital-based, thereby excluding outpatient stroke events. Stroke patients with mild symptoms might not come to hospital and patients with very severe stroke may die before they reach to hospital. Thus, stroke mortality may be underestimated in our study. 5. Conclusion Ethiopian patients suffer stroke at a relatively young age, and the proportion of hemorrhagic stroke is higher than in Western countries. Hypertension is the most common risk factor for both ischemic and hemorrhagic strokes. In-hospital stroke mortality in our population exceeds that of high income countries. More than half of the patients were discharged with severe disability. Creation of public awareness on stroke risk factors remains the most important measure to reduce stroke burden. Establishing stroke units in Ethiopia is important in order to reduce stroke mortality and post stroke disability. Acknowledgments We would like to thank Hawassa University for funding this research. We are grateful to all patients and their families who took part in this study. The authors are also grateful to Professor James C. Johnston for reviewing the manuscript. Source of funding: Hawassa University Conflict of interest: none. References [1] R.L. Sacco, S.E. Kasner, J.P. Broderick, L.R. Caplan, J.J. Connors, A. Culebras, et al., An updated definition of stroke for the 21st century: a statement for healthcare professionals from the American Heart Association/American Stroke Association, Stroke 44 (2013) 2064–2089. [2] R. Lozano, M. Naghavi, K. Foreman, S. Lim, K. Shibuya, V. Aboyans, et al., Global and regional mortality from 235 causes of death for 20 age groups in 1990 and 2010: a systematic analysis for the Global Burden of Disease Study 2010, Lancet 380 (2012) 2095–2128. [3] C.J.L. Murray, T. Vos, R. Lozano, M. Naghavi, A.D. Flaxman, C. Michaud, et al., Disability-adjusted life-years for 291 diseases and injuries in 21 regions, 1990–2010: a systematic analysis for the Global Burden of Disease Study 2010, Lancet 380 (2012) 2197–2223. [4] V.L. Feigin, M.H. Forouzanfar, R. Krishnamurthi, G.A. Mensah, M. Connor, D.A. Bennett, et al., Global and regional burden of stroke during 1990–2010: findings from the Global Burden of Disease Study 2010, Lancet 383 (2014) 245–254. [5] WHO, WHO Global InfoBase, https://apps.who.int/infobase/Mortality.aspx2011 (Accessed 19 Sep. 2012). [6] G. Zeneb, M. Alemayehu, J. Asmera, Characteristics and outcomes of stroke at Tikur Anbessa Teaching Hospital, Ethiopia, Ethiop. Med. J. 43 (2005) 251–259. [7] P.K. Nyame, K.B. Jumah, S. Adjei, Computerized tomographic scan of the head in evaluation of stroke in Ghanaians, East Afr. Med. J. 75 (1998) 637–639. [8] W. Matuja, M. Janabi, R. Kazema, D. Mashuke, Stroke subtypes in black Tanzanians: a retrospective study of computerized tomography scan diagnoses at Muhimbili National Hospital, Dar es Salaam, Trop. Dr. 34 (2004) 144–146. [9] J. Matenga, I. Kitai, L. Levy, Strokes among black people in Harare, Zimbabwe: results of computed tomography and associated risk factors, BMJ 292 (1986) 1649–1651.
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