Abstract
Background: Refractive errors are the most common cause of visual impairment worldwide, affecting over 2.3 billion people and significantly impacting quality of life if left uncorrected. These errors, including myopia, hypermetropia, and astigmatism, arise due to improper focusing of light on the retina and are influenced by both genetic and environmental factors. The ABO blood group system, first discovered by Karl Landsteiner, represents one of the most significant genetic markers in human populations and has been linked with susceptibility to various diseases. Limited research has explored the possible association between refractive errors and ABO blood groups, suggesting that certain blood groups may predispose individuals to specific types of refractive errors. Given the scarcity of local studies, it is important to investigate whether any relationship exists between blood group distribution and refractive errors in patients visiting the University of Lahore Teaching Hospital (UOLTH).
Objective: Frequency of refractive errors in different ABO blood groups among patients visiting University of Lahore Teaching Hospital Lahore.
Methodology: A descriptive cross-sectional study of patients visiting eye department was carried out by evaluating frequency of refractive errors in different blood groups. Blood group of each patient has been checked. All patients from the age 17 to 35 years visiting the department with any type of refractive error and blood group included in the study irrespective of their sex.
Results: A total of 215 patients were assessed. 21 patients are astigmatism with frequency of 9.8 of all. 3 patients have AB+,4 patients have A+,7 have B+, 5 have O+, and 2 patients have O- blood groups. 25 patients are hyperopic and 11.5% is frequency of all. 6 patients have A+, 3 have AB+, 10 have B+ and 6 have O+ blood groups. 169 patients were myopic and 78.6% is frequency of all.4 patients have A-, 26 have A+, 1 have AB-, 19 have AB+, 5 have B- blood group, 73 have B+ blood group, 3 have O- blood group and 3 have O+ blood groups. In case of left eye out of 215, 23 patients are astigmatic and frequency is 10.7% of all. 3 patients have AB+, 4 patients have A+, 9 patients have B+, 5 patients have O+ and 2 patients have O- blood group. 25 patients are hyperopic and 11.6% is frequency of all. 6 patients have A+, 3 patients have AB+,10 patients have B+ and 6 patients has O+ blood group. 167 patients are myopic and frequency is 77.7% of all. 4 patients have A-, 26 have A+, 1 patient has AB-, 19 have AB+, 5 patients have B-, 71 patients have B+, 3 patients have O- and 38 patients have O+ blood group.
Conclusion: This study concludes that highest frequency of refractive error is found among blood group B+, followed by blood group O+.