Ethnic variations in risk factor profile, pattern and recurrence of non-cardioembolic ischemic stroke.

BACKGROUND: Ischemic stroke is influenced by ethnic and geographical variations. The aim of this study was to identify the risk factor profiles, subtypes and recurrence of non-cardioembolic ischemic stroke for the two largest subpopulations, the Arab and South Asians, at the only stroke-admitting hospital in Qatar.
METHODS: Data on stroke patients admitted to Hamad Medical Corporation from January through December 2001 were reviewed in January 2005. Only patients with non-cardioembolic ischemic stroke and complete work-up were included.
RESULTS: A total of 303 patients with ischemic non-cardioembolic stroke fit the entry criteria. Sixty seven percent of the overall patient population (sex ratio 2:6, M/F) was of Arab origin, and 32% were South Asians. Hypertension was the most commonly encountered risk factor followed by dyslipidemia, diabetes mellitus, and obesity. Significant differences between the Arab and South Asian subgroup of patients were observed with respect to number of risk factors and occurrence of obesity and diabetes. Carotid artery stenotic lesions, ventricular wall motion abnormalities and stroke recurrence were observed with a higher frequency in the Arab subgroup of patients compared with the South Asians. The majority of strokes were lacunar hemispheric strokes (68%), followed by lacunar brainstem strokes (15%) and large-vessel hemispheric infarctions (10%). Patients with a previous history of stroke had a higher frequency of carotid artery stenosis (p = 0.05) and risk of stroke recurrence (p = 0.04).
CONCLUSIONS: Unlike in other studies originating from the Arabian Gulf, lacunar stroke is the most common subtype of non-cardioembolic ischemic stroke in both the Arabs and South Asians in Qatar. Significant ethnic differences in age of occurrence, risk factor profile, and cardiovascular variables were observed.