# Impact of ABO Blood Group on Bleeding and Clotting Time Among Healthy North Indian Males: A Pilot Study

## TL;DR

This study finds that people with blood type O have longer bleeding and clotting times compared to other blood types in a group of healthy North Indian males.

## Contribution

The study provides new empirical evidence on the association between ABO blood groups and hemostatic parameters in healthy North Indian males.

## Key findings

- Blood group O individuals had significantly longer bleeding and clotting times compared to non-O groups.
- No significant differences were observed in age, BMI, hemoglobin, or platelet count across ABO groups.
- The results suggest a potential clinical relevance of ABO blood type in assessing bleeding risk.

## Abstract

Background: The ABO blood group system plays a significant role in hemostasis through its influence on plasma von Willebrand factor (vWF) and factor VIII levels. Individuals with different ABO phenotypes exhibit variable coagulation profiles, potentially predisposing certain groups to bleeding or thrombotic tendencies. However, data focusing specifically on healthy North Indian males remains limited.

Objective: The objective of this study is to investigate the association between ABO blood types and hemostatic parameters, specifically clotting time (CT) and bleeding time (BT), in a group of healthy adult males from North India.

Methods: This cross-sectional study involved 200 healthy males aged 18 to 45 who were enrolled in the Department of Physiology of the Integral Institute of Medical Science and Research in Lucknow, India. The blood was grouped using the traditional slide agglutination technique. BT was measured using Duke's filter paper method, while CT was determined using the capillary tube method. Statistical analysis was conducted using IBM Corp. Released 2020. IBM SPSS Statistics for Windows, Version 26. Armonk, NY: IBM Corp. Continuous variables were summarized as mean ± SD. Group differences across ABO blood groups were evaluated using one-way ANOVA, followed by Tukey and Bonferroni post-hoc tests for significant results. A p-value < 0.05 was considered statistically significant.

Results: Among 200 healthy North Indian males analyzed, blood group B was the most common (36%), followed by O (29%), A (23%), and AB (12%), with a predominance of Rh-positive individuals (95.5%). Significant variation in hemostatic parameters was observed across ABO groups. Individuals with blood group O demonstrated the longest bleeding time (3.75 ± 0.49 min) and clotting time (6.45 ± 0.86 min), while groups A, B, and AB exhibited shorter values. One-way ANOVA confirmed significant intergroup differences for both bleeding time (p < 0.001) and clotting time (p < 0.001), whereas age, BMI, hemoglobin, and platelet count did not differ significantly across groups. Post-hoc analyses using Tukey and Bonferroni methods revealed that group O differed significantly from all non-O groups for both parameters. No significant differences were found among the A, B, and AB groups.

Conclusion: Blood group O individuals demonstrated significantly prolonged bleeding and clotting times compared with non-O groups, likely reflecting lower plasma levels of von Willebrand factor and factor VIII. These results highlight the influence of the ABO blood type on hemostatic balance and emphasize its potential clinical relevance in preoperative screening, transfusion management, and evaluation of bleeding risk.