|Year : 2013 | Volume
| Issue : 2 | Page : 55-59
Profile of stroke patients seen in a tertiary health care center in Nigeria
Sani A Abubakar1, Anas A Sabir2
1 Department of Medicine, Ahmadu Bello University Teaching Hospital, Zaria, Nigeria
2 Department of Medicine, Usmanu Danfodiyo University Teaching Hospital, Sokoto, Nigeria
|Date of Web Publication||23-May-2014|
Sani A Abubakar
Department of Medicine, Ahmadu Bello University Teaching Hospital, Zaria
Source of Support: None, Conflict of Interest: None
| Abstract|| |
Background: The profile of patients seen with acute stroke has been sparsely described in north-western Nigeria, even though stroke constitutes an important cause of severe disability in adults.
Aims: (1) The primary aim is to determine the clinical and socio-demographic profile of stroke patients seen in a tertiary hospital. (2) The secondary aim is to determine the 30-day case fatality.
Patients and Methods: A retrospective study carried out using the case records of patients admitted from January 2007 to December 2009 with the clinical diagnosis of stroke at Usmanu Danfodiyo University Teaching Hospital. Relevant clinical data were extracted using a structured questionnaire designed for the study.
Results: A total of 370 case files with the clinical diagnosis of stroke were traced, but only 260 had complete information. The mean age of patients was 55.7 ± 14.3 years; hypertension (74.6%) was the most common modifiable risk factor for stroke followed by diabetes mellitus (8.8%). Stroke constituted 1.2% of all hospital admissions and 8.5% of death in the medical units. The 24-h and 30-day case fatalities were 11.9% and 38.4%, respectively. The mean duration of hospitalization for stroke survivors was 21 days, but the duration of hospitalization prior to death for those that died was 4 days.
Conclusion: The 30-day case fatality of acute stroke was high and hypertension was the most common modifiable risk factor for stroke. Prompt and adequate measures should be taken to improve outcome of stroke.
Keywords: 30-day mortality, risk factors, stroke
|How to cite this article:|
Abubakar SA, Sabir AA. Profile of stroke patients seen in a tertiary health care center in Nigeria. Ann Nigerian Med 2013;7:55-9
| Introduction|| |
Stroke is the most important single cause of severe disability in adults and the second most common cause of death after coronary heart disease.  In developing countries, increased life expectancy has modified the pattern of cause-specific mortality, with a higher burden of cardiovascular diseases. , The importance of stroke in low-income and middle-income (developing) countries has recently become better appreciated and highlighted by the recently updated estimate from the global burden of disease study, which shows that over 80% of all stroke death occurs in low-income and middle-income regions of the world.  The frequency of stroke in hospital populations has varied from 0.9% to 4.0%, whereas among neurological admissions stroke accounted for 0.5-45%.  At Lagos University Teaching Hospital (LUTH), stroke was the most common cause of neurological admission.  In sub-Saharan Africa, most hospital series reported a high risk of death from stroke with more than 30% of patients dying within the 1 st month of onset of stroke.  A recent retrospective study in South-south Nigeria  revealed in-hospital mortality of 7.8%. In a prospective study of 318 patients in the Ibadan stroke registry,  207 were alive at 3 weeks, but only 76 (24%) were alive at 3 months.
Despite efficacious treatment against stroke, mortality and disability resulting from stroke is still high. Therapeutic measures need to be administered as soon as possible after stroke onset, so as to enhance the outcome This study aims to determine the socio-demographic profile of patients admitted to Usmanu Danfodiyo University Teaching Hospital (UDUTH), Sokoto with diagnosis of acute stroke, as well as to determine 30-day case fatality. This may thus provide insight into public health measures that can help reduce the burden of stroke in Nigeria.
| Patients and Methods|| |
We conducted a retrospective study of patients admitted to UDUTH Sokoto between January 2007 and December 2009. UDUTH is a tertiary health care institution situated in Sokoto, a predominately urban setting in north-western Nigeria with a population of about 427,760 people.  It receives referral cases predominately from primary and secondary health care institutions in Sokoto and neighboring states. It however also receives emergencies either by physicians or on self-referral. The hospital has 585 in-hospital beds with 96 of these being in the medical wards. Patients were admitted mostly through the accident and emergency unit and medical out-patients clinics and subsequently transferred to medical wards within 24 h. Surviving patients were discharged to medical out-patients clinics for subsequent follow-up.
Case records of patients with the clinical diagnosis of stroke (first and recurrent) were traced, having obtained permission from appropriate authorities. These were case notes of patients that were admitted into an accident and emergency unit, casualty medical observation and medical wards. A questionnaire was designed and used to extract relevant clinical data from the case records. This questionnaire recorded the age, sex, date of admission, time of death, stroke risk factors, admission blood sugar and level of consciousness. Outcome at 30-day was categorized as either alive or dead. Hypertension was taken as positive history, use of anti-hypertensive drugs or persistently elevated blood pressure (>140/90 mmHg) while on admission. Diabetes mellitus was regarded as a positive history, use of hypoglycemic agents or a fasting plasma glucose of >7.0 mmol/L on two occasions. Stroke was defined as a clinical syndrome of sudden onset of rapidly developing symptoms and signs of focal or global cerebral deficit with symptom lasting more than 24 h or leading to death with no apparent cause other than vascular origin.  Brain computed tomography (CT)-Scan was used for stroke classification and where not available, Sirirag stroke score was used.  The case fatality at 24 h and 30 days were recorded.
Data analysis was performed using SPSS 18.0 (IBM Corporation, Armonk, NY, USA). Frequency, means and standard deviation were generated using descriptive statistics. Quantitative (continuous) variables were compared using Student's t-test. Chi-Square was used to compare categorical variables. Statistical significance was fixed at P < 0.05.
| Results|| |
During the 36 months study period, 3565 patients were admitted to the medical unit, of whom 370 (10.4%) had a diagnosis of acute stroke. Excluded from the study were 70 patients with incomplete records and 40 patients who signed against medical advice. Thus, only 260 case records with complete information were included in the study. Of these, 145 (55.8%) were males and 115 (44.2%) were females with a male:female ratio of 1.3:1. The overall mean age of patients was 55.7 ± 14.3 years. Most of the patients were of Hausa-Fulani extraction constituting 85.4% of respondent, this was followed by Yoruba (3.8%) and Dakarkari (2.3%). About (47.7%) of the patients presented within 24 h of onset of symptom of stroke. The baseline characteristics of the patients are shown in [Table 1]. Female (56.5 ± 15.4 years) patients were older than males (55.2 ± 13.5 years) and had a higher mean admission diastolic blood pressure, though this was not statistically significant (P = 0.62). Systemic hypertension was the most common modifiable risk factor for stroke occurring in 74.8% followed by diabetes mellitus. Thirty four patients developed acute stroke complications with aspiration pneumonia being the most frequent, occurring in 5.7% of the patients.
Overall 100 patients died within 30 days, giving 30-day case fatality of 38.4% with 31% of patients dying within 24 h of hospitalization. A total of 90 patients had brain CT-scan confirmation of their stroke, with cerebral infarction accounting for 64.4% [Table 2]. Three patients had a normal finding on brain CT-scan and were considered as cerebral infarction.
The mean age of patients that died within the 30 days of hospital admission was 58.5 ± 13.2 years, which is significantly higher (P = 0.013) than those that survived beyond 30 days. Stroke complications were also found to be higher among patients that died as shown in [Table 3].
| Discussion|| |
This study showed that stroke constituted 1.2% of all hospital admission in Sokoto and 7.3% of admissions to the medical wards. This is similar to the frequency reported by Ojini and Danesi  at LUTH. It also accounted for 2.4% of all deaths in the hospital and 8.5% of medical deaths. This is similar to findings in south western part of Nigeria. ,, The patients were predominately middle aged (mean 55.7 years), which is comparable to the finding by Wahab et al.  in a retrospective study carried out at the same study site. A multi-center prospective study that aimed at validating Sirirag stroke score also found stroke to occur predominately in middle aged (mean age of 54 ± 9 years) individuals.  The male to female ratio of 1.3:1 showed male preponderance, though stroke is said to more common in male than females. This may reflect the fact that women are less likely than men to go to hospital for cultural reason rather than the difference in incidence. This male preponderance is in disagreement with other studies that suggested changing pattern in sub-Saharan Africa. ,
Hypertension was the most common modifiable risk factor for stroke occurring in 75.7% which is similar to findings in previous studies in Nigeria , but higher than 65.4% and 65.8% reported by Wahab et al.  and Imam and Olorunfemi,  respectively. Although the reasons why hypertension increases stroke risk are multi factorial, hypertensive individuals have reduced nitric oxide and increased endothelin-1.  The former is a vasodilator with anti-atherosclerosis effect while the latter is a vasoconstrictor with pro-atherosclerotic effect. Hypertension predisposes to hyalinosis of small blood vessel in the brain, with resultant formation of Charcot-Bouchard micro-aneurysm, which with rupture leads to intracerebral hemorrhage. Thus, the control of systemic hypertension remains central in primary prevention of stroke. Diabetes was responsible for stroke in 8.8% of patients which is lower than 20-30% reported in western , literature, but similar to 8.0% and 8.5% reported by Bwala  and Osuntokun et al.  respectively in Nigeria.
Using brain CT-scan, cerebral infarction accounted for 64.4% of stroke while primary intracerebral hemorrhage accounted for 31.1%. This is in agreement with a previous study that reported a changing pattern with increased frequency of hemorrhagic stroke.  This however disagrees with the finding of 45% frequency of hemorrhagic stroke reported in a 10-year retrospective study in Nigeria.  This difference could be explained by the fact that in the current study stroke classification was based only on brain CT-scan confirmation while the other study used Siriraj stroke score.
Thirty four (13.1%) patients developed some complications during the study period which is higher than 11.4% reported by Heuschmann et al.  in the German stroke register study group. This higher frequency of complications may not be unconnected to the fact that most stroke patients in the German group were managed in the stroke units perhaps with strict protocols, which is not the case in our setting. In north eastern Nigeria, 38.4% of their patients developed one form of complication or the other.  Aspiration pneumonia was the most common acute stroke complication. This is probably because before being brought to the hospital, most patients were orally fed by relatives despite reduced level of consciousness. Death was the eventual outcome in 38.5% of patients within 30 days of stroke onset with 31% of those deaths occurring within 24 h of hospitalization. A similar frequency of this 30-day case fatality was reported from in south western Nigeria.  The 24-h case fatality of 11.9% in this study is however higher than 8.5% reported in the their series. This difference in frequency could possibly be that the patients in this cohort may have presented with more severe stroke at presentation and the sample size is smaller in this study. Mean age (58.5 years) of patients that died within 30 day was significantly higher than those that survived (P = 0.01), which is in agreement with finding of Rallidis et al.  Mean admission blood glucose was also found to be significantly lower in those that survived (P < 0.001), which support the fact that high admission blood sugar are associated with poor outcome.  Patients who died within 30 days had reduced level of consciousness as measured by Glasgow Coma Scale. This is in keeping with the findings that suggested that level of consciousness as measured by Glasgow coma Scale is an important predictor of outcome. 
| Conclusion|| |
Based on the above study it can be concluded that 30-day case fatality was 38.4% with most of the death occurring within 24 h of hospital admission. Systemic hypertension was the most common modifiable risk factor stroke. The limitation of this study is its retrospective design. A large prospective study is required to establish detailed risk factor profile and determine predictors of mortality in order to optimize outcome of stroke in Sokoto-Nigeria.
| Acknowledgments|| |
The authors would like to thank Mallam Mohammed B. Almajir and Mallam Sanusi of Medical Records Department, UDUTH, Sokoto, for their assistance with retrieval of case notes.
| References|| |
|1.||Murray CJ, Lopez AD. Mortality by cause for eight regions of the world: Global Burden of Disease Study. Lancet 1997;349:1269-76. |
|2.||The World Health Organization MONICA Project (monitoring trends and determinants in cardiovascular disease): A major international collaboration. WHO MONICA Project Principal Investigators. J Clin Epidemiol 1988;41:105-14. |
|3.||Lopez AD, Mathers CD, Ezzati M, Jamison DT, Murray CJ. Global and regional burden of disease and risk factors, 2001: Systematic analysis of population health data. Lancet 2006;367:1747-57. |
|4.||Ojini FI, Danesi MA. Pattern of neurological admissions at Lagos University Teaching Hospital. Niger J Clin Pract 2003;5:38-41. |
|5.||Ogun SA, Ojini FI, Ogungbo B, Kolapo KO, Danesi MA. Stroke in south west Nigeria: A 10-year review. Stroke 2005;36:1120-2. |
|6.||Ansa VO, Bassey EO, Ekrikpo U. Predictors of in-hospital mortality among stroke patientsin Uyo, Nigeria. Port Harcourt Med J 2012;2:170-5. |
|7.||Osuntokun BO, Bademosi O, Akinkugbe OO, Oyediran AB, Carlisle R. Incidence of stroke in an African City: Results from the Stroke Registry at Ibadan, Nigeria, 1973-1975. Stroke 1979;10:205-7. |
|8.||National Population Commission. Facts and Figures of 2006 Census in Nigeria. Available from: http://www.Nationalpopulationcommission.com. [Last accessed on 2012 Mar 12]. |
|9.||Kolapo KO, Ogun SA, Danesi MA, Osalusi BS, Odusote KA. Validation study of the Siriraj stroke score in African Nigerians and evaluation of the discriminant values of its parameters: A preliminary prospective CT scan study. Stroke 2006;37:1997-2000. |
|10.||Ogun SA, Adelowo OO, Familoni OB, Jaiyesimi AE, Fakoya EA. Pattern and outcome of medical admissions at the Ogun State University Teaching Hospital, Sagamu - A three year review. West Afr J Med 2000;19:304-8. |
|11.||Adetuyibi A, Akisanya JB, Onadeko BO. Analysis of the causes of death on the medical wards of the University College Hospital, Ibadan over a 14-year period (1960-1973). Trans R Soc Trop Med Hyg 1976;70:466-73. |
|12.||Wahab KW, Sani MU, Samaila AA, Gbadomasi A, Olokoba AB. Stroke at a tertiary medical institution in northern Nigeria: patients profile and predictors of outcome. Sahel Med J 2007;10:6-10. |
|13.||Wahab K, Okubadejo N, Ojini F, Danesi M. Effect of admission hyperglycaemia on short-term outcome in adults Nigerians with first-ever acute ischaemic stroke. Afr J Neurol Sci 2007;26:48-57. |
|14.||Okubadejo NU, Ojini FI, Dawodu CO, Danesi MA. Does the diagnosis of hypertension prevent stroke? A preliminary investigation of relative frequency of undiagnosed and previously diagnosed hypertension before first stroke in a Lagos Hospital. Nig Q J Hosp Med 2002;12:10-2. |
|15.||Bwala SA. Stroke in a subsaharan Nigerian hospital - A retrospective study. Trop Doct 1989;19:11-4. |
|16.||Imam I, Olorunfemi G. The profile of stroke in Nigeria's federal capital territory. Trop Doct 2002;32:209-12. |
|17.||Böhm F, Pernow J. The importance of endothelin-1 for vascular dysfunction in cardiovascular disease. Cardiovasc Res 2007;76:8-18. |
|18.||Heuschmann PU, Kolominsky-Rabas PL, Misselwitz B, Hermanek P, Leffmann C, Janzen RW, et al. Predictors of in-hospital mortality and attributable risks of death after ischemic stroke: The German Stroke Registers Study Group. Arch Intern Med 2004;164:1761-8. |
|19.||Rallidis LS, Vikelis M, Panagiotakos DB, Rizos I, Zolindaki MG, Kaliva K, et al. Inflammatory markers and in-hospital mortality in acute ischaemic stroke. Atherosclerosis 2006;189:193-7. |
|20.||Osuntokun BO, Odeku EL, Adeloye RB. Cerebrovascular accidents in Nigerians: A study of 348 patients. West Afr Med J Niger Pract 1969;18:160-73. |
|21.||Ogun SA. Acute stroke mortality at Lagos University Teaching Hospital-a 5 year review. Nig Q J Hosp Med 2000;10:8-10. |
|22.||Watila MM, Ndayati YW, Balarabe SA, IbrahimA, Alkali NH, Gezawa ID, et al. Medical complications among stroke patients at the university of Maiduguri teaching hospital, Northeastern Nigeria. J Med Med Sci 2012;3:189-94. |
|23.||Tsao JW, Hemphill JC 3 rd , Johnston SC, Smith WS, Bonovich DC. Initial Glasgow Coma Scale score predicts outcome following thrombolysis for posterior circulation stroke. Arch Neurol 2005;62:1126-9. |
[Table 1], [Table 2], [Table 3]