Variations in activated partial thromboplastin time and prothrombin time in individuals of A, B, AB, and O blood groups

Background: Differences in blood group have been associated with predisposition to some diseases. Activated partial thromboplastin time (APTT) measures the efficiency of the intrinsic and common coagulation pathways, whereas prothrombin time (PT) test assesses the extrinsic and common coagulation pathways. Objective: The aim of this study was to assess the variations in PT and APTT among individuals of different ABO blood groups. Materials and Methods: A research was conducted at College of Health Sciences, Nnamdi Azikiwe University, Nnewi Campus, and a total of 200 students were recruited, consisting of 106 females and 94 males. Six milliliters of blood was withdrawn from each individual, after obtaining ethical clearance and informed consent. ABO blood grouping was done by the tile method while APTT, and PT were analyzed using the standard manual methods. Statistical analysis was carried out using Statistical Package for the Social Sciences version 21. Results: The result shows that blood group O was predominant among the test individuals (45%) followed by blood groups A (31%) and B (15%), while blood group AB has the least percentage (9%). Blood group O showed a significantly higher APTT value (44.24 ± 15.10 s) compared to blood groups A (39.35 ± 12.12 s), B (35.93 ± 9.78 s), and AB (37.22 ± 8.15 s) (P < 0.05). Similarly, blood group A showed a significantly higher PT value (16.70 ± 2.53 s) compared to blood groups O (14.32 ± 2.37 s), B (13.53 ± 2.16 s), and AB (15.38 ± 1.79 s) (P = 0.05). Blood groups B and AB male individuals had a significantly higher PT and APTT levels, respectively, when compared with females (P < 0.05). Conclusion: This study showed that APTT and PT levels differ among different ABO blood groups; therefore, variations in blood group of individuals may affect their intrinsic and extrinsic coagulation mechanisms