Prevalence, Characteristics and Risk Factors for Embolic Stroke of Undetermined Source in West and South Asia and North African Population Residing in Qatar

Background and Purpose: Embolic stroke of undetermined source (ESUS) is an important contributor to stroke worldwide. Little is known about ESUS in developing parts of the world such as South Asia, West Asia and North Africa despite the high stroke burden in these areas. The purpose of the study was to characterize the prevalence, demographic, risk factor and clinical aspects of ESUS in patients from South Asia, West Asia and North Africa residing in Qatar. Methods: Data were retrospectively collected on 3103 stoke patients. Risk factors and clinical features of the ESUS group were compared to all other strokes using Chi-square or student's t-tests. Logistic regression was used to identify factors associated with ESUS. ESUS patients were compared based on ethnicity using Chi-square or one-way ANOVA. Results: 634 patients (30.9%, 95% CI (28.9%-32.9%) met the ESUS criteria. Mean age was 56.3 years +/- 13.7 and South Asian ESUS patients were younger than West Asians or North Africans (67.1 +/- 13.5 versus 52.1 +/- 10.8 versus 53.5 +/- 14.2, P = .001). Smoking, diastolic function, prior antiplatelets and wall motion abnormalities were more common in ESUS. Logistic regression showed that South Asian ethnicity (OR 1.50, CI 1.14-1.97, P = .003), diastolic dysfunction (OR 1.47, CI 1.23-1.75, P = .005), global (OR 1.79, CI 1.41-2.26, P = .001) and focal (OR 5.48, CI 3.79-7.92, P = .001) wall motion abnormalities, predicted ESUS. Conclusions: ESUS is a major cause of stroke in patients from West Asia, South Asia and North Africa residing in Qatar. The clinical profile and risk factors for ESUS vary based on ethnicity. In South Asians, ESUS occurs at a younger age and is most likely cardiogenic in origin.