Abstract
Background: The clinical significance of the ABO blood group system extends beyond transfusion medicine as several reports have suggested an important involvement in the development of neoplastic and cardiovascular disorders, peptic ulcers, coagulation and infection. Objective: to show the prevalence of hypothyroidism in various ABO and Rh blood group subjects, and to examine the strength of association between hypothyroidism and ABO, Rh blood groups subjects in Arar City, Northern Saudi Arabia. Methods: A cross-sectional study, conducted in Arar city, Northern Saudi Arabia. During the period from 1 January to 31 May 2018. The study included 746 participants. Collected data analyzed using the SPSS program (version 22). Pvalue of less than 0.05 considered statistically significant. Results: the total prevalence of hypothyroidism was 5.9%. As regards the blood group, blood group O was the most common (44.5%), followed by blood group A (26.7 %) and B (20.8 %), and the least common one was AB (8%). Rhesus factor (Rh) was positive in 86.1% and negative in 13.9%. The majority (86.4%) of hypothyroid patients were females (P value=0.0001). The data show a significant difference in hypothyroidism in the different blood groups (P value=0.048) with group A subjects of the highest association (8% of group A subjects). Rh blood type had no statistically significant association with hypothyroidism. Conclusion: The results of our study showed a significant difference in hypothyroidism in the different blood groups with group A subjects of the highest association. Our findings support the need for further investigation to look for the association between ABO blood groups and hypothyroidism, further investigations in a larger population are warranted.