Blood group and its correlation with cardiovascular risk factors: A community survey

Cardiovascular disease is a leading cause of morbidity and mortality globally. Non-O blood groups have been shown to confer a high risk of coronary heart disease. There is paucity of data on the relationship between blood group and left ventricular hypertrophy, among other cardiovascular risk factors. A community-based study was done to evaluate the blood groups and their associations with conventional cardiovascular risk factors in Ejigbo. Anthropometry, blood pressure and other clinical variables were measured. Blood samples were taken for biochemical analysis for blood group typing, serum cholesterol and triglyceride assay. A 12- lead electrocardiogram was performed. The analysis was done using SPSS version 20 to determine possible relationships between the variables. Two hundred and six cases were recruited and analyzed. The prevalence of the various groups was as follows: A - 23%; B-31.4%; AB-4.4%; O-41.2%; rhesus-positive-92.7% and rhesus-negative-7.3%. Blood group B had similar systolic blood pressure (136.0±23.9 vs 137.3±22.3; p=0.726), higher Sokolow- Lyon voltage sum (3.3±1.1 vs 2.9±0.9; p=0.025) and serum triglycerides [14(21.9%) vs7(8.4%), p=0.021] than those with blood group O. Those with Rhesus Positive status had longer PR interval (169.3±25.4 vs 154.2±19.1; p value=0.055) and QRS duration (83.8±12.8 vs 78.4±7.6; p value=0.043) than those with Rhesus negative blood groups. Binary logistic regression revealed blood group B as an independent determinant of left ventricular hypertrophy( LVH) (OR: 3.028; p=0.012; 95% CI:1.275-7.192). Blood group B is a determinant of LVH. Rhesus positive status is associated with delayed electrical conduction through the myocardium.