1. Dr. Asma AL-Nuaimi, B.Sc., Senior Resident Community Medicine (R3),
Correspondence author
Hamad Medical Corporation.
Tel. +974 4473223
Fax: +974 4473223
Cell phone: +974/5859053
E-mail:

2. Dr. Rasha Elsayed Salama (Salama RE, M.Sc., M.D.) Community Medicine Lecturer
Tel. +974 4473215
Fax: +974 4473223
Cell phone: +974 5973314
Email: rashasalama2004@yahoo.com

3. Dr. Essa Mubarak Al Sulaiti, Chairman of Geriatrics Department (HMC)
Tel. +974 4397006
Cell phone: +974 5535549
Email: emsulaiti@yahoo.co.uk

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INTRODUCTION

A stroke is a clinical condition characterized by a sudden focal neurological deficit or acute neurological impairment caused by the interruption of blood flow to a specific region of the brain. This leads to an abnormal brain function causing disability, including paralysis as well as speech and emotional problems. Stroke can be classified into: ischaemic stroke, hemorrhagic stroke, and transient ischaemic attacks. Ischaemic stroke is the most common type that occurs, and happens due to blood clots or narrowing of the brain supplying arteries.^1,2
Stroke constitutes a major global challenge for health policy and healthcare economics; annually 15 million people worldwide suffer a stroke. Of these, 5 million die and another 5 million are left permanently disabled, placing a burden on family and community. Globally, stroke is the second leading cause of death.^3,4
WHO estimated that in 2005 stroke accounted for 5.7 million deaths worldwide. In developed countries stroke is the third leading cause of death and the leading cause of disability. More than half a million people experience a new or recurrent stroke each year.^3,4
In Qatar, stroke is one of the most common causes of disabilities. There is inadequate data about stroke. In 2003, 12 deaths were encountered due to stroke in the country.⁵
Risk factors of stroke include two major forms: modifiable factors such as high blood pressure, abnormal blood lipids, tobacco use, physical inactivity, diabetes mellitus, unhealthy diet, and atrial fibrillation. On the other hand; non-modifiable factors include advanced age, heredity factors or family history, gender, and ethnicity or race.^6,7
Worldwide there are some preventive programs planned and implemented in order to achieve their mission to reduce premature death and disability from stroke among the elderly, targeting people at risk for stroke, including persons with high blood pressure, high cholesterol, and multiple risk factors, as well as persons with prior stroke. Interventions with these populations directly address Healthy People 2010 objectives for stroke.
In Qatar, a hospital-based study was conducted to determine the types and the 30-day fatality rate of stroke. First-ever stroke was found in 217 patients (157 men and 60 women). The overall incidence rate was 41 per 100,000 inhabitants per year (95% CI, 30.2-52.4/100,000/year) and 238/100,000/year for the population over 45 years old. The age standardized incidence was 57.5 per 100,000 inhabitants per year (95% CI, 43.1-73.8). The crude incidence for native Qataris was 75 per 100,000 inhabitants per year. The mean age of patients experiencing their first stroke was 57 years. Thirty-nine (18%) patients were younger than 45 years. Clinical subtypes of stroke were ischemic (80%), intracerebral hemorrhage (19%), and subarachnoid hemorrhage (1%). Risk factors included hypertension (63%), diabetes mellitus (42%), ischemic heart disease (17%), and atrial fibrillation (4.5%). The overall patient fatality rate at 30 days was 16%.⁸
Stroke incidence in Qatar is lower than in other countries; a low incidence of subarachnoid hemorrhage was noted. The low mean age of stroke patients reflects the demographic characteristics of the population in Qatar. The high percentage of stroke patients suffering from hypertension and diabetes reflects the high prevalence of these risk factors in the population.⁸
To my knowledge there is no such preventive program for stroke in Qatar and there were limited studies assessing risk factors for stroke and to plan and implement preventive program for stroke, thus the risk factors for stroke in Qatar must be identified and controlled.

Aim of the Study
To study stroke risk factors in Qatar and to recommend better control programs toward them.

Objective of the Study
To determine the prevalence of the major risk factors: (diabetes, hypertension, hyperlipidemia, and smoking) among elderly stroke patients in Doha in 2007.

METHODOLOGY

Study Design: This study is a cross sectional study.
Study Setting: The study was conducted in Rumaillah Hospital in Doha-Qatar. Qatar is a small country with an area of 11,427 sq. km, population of 7,24,125 and is densely populated at the capital city of Doha. Rumailah Hospital is a hospital that delivers the highest quality of specialized acute, rehabilitative and long-term care services through comprehensive and holistic care continuum to patients including stroke patients.
Study Population: Elderly patients diagnosed as having stroke at different clinical settings in Rumaillah Hospital: inpatient, outpatient, and home care departments.

Case Definitions:

Stroke patients: include all cases diagnosed by clinical & neurological examination according to the following clinical setting: neurological weakness, incoordination, or visual losses confirmed by Computed Tomography (CT) scan or Magnetic Resonance Imaging (MRI)
Elderly: include individuals who are 60 years of age and older according to the American Institutional Health Department.

Variables of the Study:

Exposure

a. Major modifiable risk factors:
· High blood pressure
· Abnormal blood lipids
· Tobacco use
· Physical inactivity
· Obesity
· Unhealthy diets
· Diabetes mellitus

b. Other modifiable risk factors:
- Low socioeconomic status (SES)
- Mental ill-health
- Psychosocial stress
- Alcohol use
- Use of certain medication
- Lipoprotein(a)
- Left ventricular hypertrophy (LVH)

c. Non-modifiable risk factors
- Advancing age
- Heredity or family history
- Gender
- Ethnicity or race

Novel risk factors
- Excess homocysteine in blood
- Inflammation
- Abnormal blood coagulation

Outcome: Stroke

Data Collection Tools:
A study sheet was formulated for data collection and included:
a. Demographic data: age, sex, nationality, socioeconomic status, and health card number.
b. Medical history:
- Time of diagnosis of stroke
- Method used for diagnosis
- Associated medical problems and the date of their diagnosis including risk factors: (Diabetes, hypertension, and hyperlipedemia).
- Date of diagnosis of medical problems
- History of smoking, amount, and duration.
c. Family history of stroke

Data Collection Technique:
a. Primary Source: Person to person interview
- Member of household or close relative
- Caregiver
b.Secondary Source: Data was abstracted from patients' medical records to confirm the information.

Sample size:
Sample Size was calculated to be 113 cases
Sampling Technique: Simple random sampling

Data Entry and Analysis: Collected data was coded and entered to the Statistical Package of Social Science (SPSS) of software, then analyzed by suitable statistical tests:

• Central tendency measures, and measures of dispersion when appropriate
  
• Chi square and t test
  

Ethical Consideration

1. Approval was taken from the research committee
   
2. Permission from board of Rumaillah Hospital to go through the medical records of patients.
   
3. Verbal consent from the patients if conscious, or relatives.
   
4. Confidentiality of data was assured.

RESULTS

Of the total 163 elderly stroke patients registered in Rumaillah hospital, 113 patients were randomly allocated in the study according to the calculated sample size. The mean age of stroke patients included in the study was 76.40±7.96 years. The study showed that there was no significant association between gender and nationality (P=0.49) as well as between age and gender (P>0.05) among stroke patients.

Table 1 presents demographic characteristics of stroke patients included in the study. It was noticed that the frequency of males and females was approximately the same with approximate ratio of 1:1. More than 80% of the stroke patients were Qatari.

Figure 1. Frequency of the Major Risk Factors among Stroke Patients

Figure 1 demonstrates the frequency of the major risk factors; diabetes mellitus (DM), hypertension (HTN), hyperlipidemia, and smoking among stroke cases. HTN was the most frequent determined risk factor among stroke cases constituting more than 80%. DM ranked as the second risk factor that had frequency of more than 60% among stroke patients. On the other hand smoking was the least frequent risk factor constituting 3.5%.

Table 2. Association between the Major Risk Factors of Stroke and Gender

* p value for X²

Table 2 presents the association between different risk factors of stroke and gender which showed p-value >0.05 with no significant association except for smoking that had borderline significance of p= 0.05 for males.

Table 3. Association between the Major Stroke Risk Factors and Gender

* p value for X²

Table 3 showed no significant difference of the risk factors frequency between Qatari and Non-Qatari patients with stroke. P-value was estimated to be ? 0.05 with no statistical significance.

DISCUSSION

The present cross-sectional study represents the frequency of the major risk factors (HTN, DM, hyperlipidemia, and smoking) of stroke among stroke patients, which will serve to guide the health authorities in stroke prevention.
Different risk factors among stroke patients were measured. Hypertension was considered as the most frequent risk factor (81.4%) followed by diabetes mellitus (61.9%), family history of stroke (15.9%), hyperlipidemia (8.8%) and finally history of smoking (3.5%), which was considered as the least frequent risk factor among stroke patients. These results are consistent with a previous hospital-based retrospective study of stroke and risk factors in Jordan that included 200 patients with first-ever ischemic stroke admitted to hospital between 2000 and 2001. The study found that the most common risk factor was HTN (76%) followed by DM (44%).⁹ Also it is consistent with a case-control study that was conducted in China to identify the risk factors in Chinese with non-valvular atrial fibrillation and stroke, of these stroke patients (71%) had hypertension which were the majority and (17.9%) had diabetes.¹⁰ The present study results were also consistent with results in the retrospective cohort study done in UK in which data were collected for 813 new referrals of stroke and cardiovascular disease over a period of six months and found that the most common risk factors in patients referred were hypertension (52.9%). In the same study, on the other hand, smoking was found to be (31.7%) higher than the results in our study, which could be contributed to the higher prevalence of smoking behavior in the UK.¹¹ Conversely in some other studies the data were not consistent with the results of ours. A previous retrospective cohort study was done in Qatar in 1999 to 2003 for 377 patients in order to find the association between stroke and acute myocardial infarction and to assess related risk factors such as diabetes, hypertension, and atrial fibrillation. This study concluded that 46.4% of stroke patients were diabetic and 28.9% were hypertensive.¹² This difference from our study may be contributed to difference in the mean age of subjects included in their study (54.9±12.5years) while in the present study the stroke patients were (76.40±7.96years). Another reason may be due to the site of that other study which was conducted among patients hospitalized in Hammed General hospital while the present study was conducted in patients registered in Rumaillah hospital. Another study which was not consistent with ours was a retrospective clinical series study done in Nepal over 2 years including patients with stroke who were with a mean age of 61 years to study their risk factors. It found 61% smokers, 6o% hypertensive, 8% had atrial fibrillation, and 8% were diabetic.¹³ These differences in the results may be explained by several reasons; as smoking is more prevalent among males than females in Qatar or may contribute to inadequate data in our medical files. Also it may be due to different lifestyles in the different countries.
There were no significant associations found between stroke risk factors and gender or nationality, this may be explained by the fact that stroke risk factors contributed to the sedentary life style regardless of nationality or gender.

Limitations of the Study:

1. Temporal relationship cannot be confirmed in this type of study
   
2. Sample size calculation may necessitate a larger number of cases than the already existing ones in the Rumaillah hospital, hence we may have to include all cases of stroke in the hospital.
   
3. Information bias may occur due to incomplete or wrong information from patients’ relatives or medical records.
   

CONCLUSION AND RECOMMENDATIONS
From this study it is clear that hypertension is the most frequent determined risk factor among stroke patients, followed by diabetes mellitus. The least determined risk factor was smoking. There were no significant associations between stroke risk factors and gender and nationality. This suggests the necessity of planning and implementation of strong control and preventive programs addressing the major stroke risk factors in Qatar.

1. Webster's New World Medical Dictionary. Second Edition, 2003.
   
2. Centers for Disease Control and Prevention, Department of Health and Human Services. About Stroke, Dec 2006.
   
3. Khaw AV, Kessler Ch.Stroke: epidemiology, risk factors, and genetics. Hamostaseologie. 2006; 26(4):287-97.
   
4. World Health Organization, WHO Original Office for Europe. Chronic Diseases and Health Promotion. STEP wise approach to stroke surveillance, 2007.
   
5. Vital Statistics Annual Report, State of Qatar Ministry of Public Health, Preventive Health Department, 2003.
   
6. Centers of Disease Control, California Heart Disease & Stroke Prevention Program. Stroke Risk Factors. State of California, 2004.
   
7. American Heart Association. Heart and Stroke Facts: Risk Factors for Heart Disease P: 47-49, 2003.
   
8. Hamad A, Hamad A, Sokrab TE, Momeni S, Mesraoua B, Lingren A Stroke in Qatar: A one-year, hospital-based study. J Stroke Cerebrovasc Dis 2001 Sep; 10(5):236-241.
   
9. O. Khatib, Noncommunicable diseases: risk factors and regional strategies for prevention and care. Eastern Mediterranean health Journal. Volume 10, No. 6, November 2004: 778- 788.
   
10. Hu DY, Sun YH, Zhou ZQ, Li KB, Ni YB, Yang G, Sun SH, Li L, Risk factors for stroke in Chinese with non valvular atrial fibrillation: a case-control study. Zhonghua Nei Ke Za Zhi journal. 2003 Mar;42(3):157-61.
    
11. Murray S, Bashir K, Lees KR, Muir K, MacAlpine C, Roberts M, Langhorne P. Epidemiological aspects of referral to TIA clinics in Glasgow. Scott Med J. 2007 Feb;52(1):4-8.
    
12. Abdulbari Bener, Saadal Kamran, Elhadi B. Elouzi, Ayman Hamad, Richard F. Heller. Association between stroke and acute myocardial infarction and its related risk factors: hypertension and diabetes. Original Investigation. Anadolu Kardiyol Derg 2005; 5: 24-7.
    
13. Pathak V, Kanth R, Pant H. STROKE: a case series study in Nepal Medical College Teaching Hospital. Nepal Med Coll J. 2006 Sep;8(3):180-1.