Frequency of ABO Blood Group among Stroke Patients in Federal Medical Centre, Asaba and Review of Literature in Nigeria

Abstract

Introduction: Stroke is often a leading cause of morbidity and mortality in Nigeria, with hypertension and diabetes remaining as well-established risk factors. The ABO blood group system has been linked to thrombotic and cardiovascular disorders, but its association with stroke in Nigeria community is not well established. Objectives: The present study aimed to determines the frequency of ABO blood groups and to assess potential associations between Stroke patients and ABO blood groups and traditional risk factors (Hypertension and Diabetes) in Federal Medical Centre, Asaba, Nigeria. Materials and Methods: We conducted a prospective cross-sectional study of patients seen at Federal Medical Centre, Asaba, Delta State, Nigeria, from June 2023 to May 2024. Diagnosis of stroke was confirmed by a brain CT scan in all the participants. Consecutive convenient sampling technique was used in selecting 100 patients, and their Blood samples were taken and sent to the Central Laboratory of the hospital for ABO typing. Information on other risk factors, like hypertension and diabetes, was collected and analysed using SPSS V25.  Qualitative and Continuous data were described, and association was tested using the chi-square test with a 95% confidence interval. A p-value less than 0.05 was considered statistically significant Results: The Mean age of patients was 61.25 ±14.07 years. Out of the 100 patients, sixty-four were males, and 36(36%) were females, with a male-to-female ratio of 1.9:1. This study identifies ischemic stroke as the predominant subtype (70%). Hypertension occurred as the most universal risk factor, present in approximately 87% of both ischemic and hemorrhagic strokes. Remarkably, Diabetes Mellitus (DM) established a significant, specific association with ischemic stroke (40% vs. 13.3% in hemorrhagic stroke, p value 0.009), performing as a key clinical differentiator between stroke subtypes. While non-O blood groups were more prevalent (55%) than the national average, their impact on stroke risk appeared secondary. The findings suggest that older population’s influence of blood type is frequently "superseded" by the burden of DM and hypertension. Conclusion: Elderly non-blood group O patients is more prevalent than the national average. The findings suggest that older populations (mean age 61.25 years), influence of blood type is frequently "superseded" by the burden of DM and hypertension (χ² = 0.048, p = 0.826). This may be due to the dominant influence of traditional vascular risk factors in this area. Further large-scale, studies are required to clarify any causal relationship between ABO blood group and stroke risk in Nigeria.