Myopia and Digit Ratio (2D:4D) In Ningxia Medical University Students

Background Myopia is an endemic eye disease in human populations worldwide. Both environmental and genetic factors are involved in myopia development but its etiology remains largely unknown. Studies showed that the increased prevalence of myopia in females suggests an association with sex hormone exposure. The second-to-fourth digit ratio (2D:4D) has been proposed as a biomarker of prenatal testosterone exposure. In this study, we explored the association between myopia and 2D:4D of students attending Ningxia Medical University in Yinchuan, China. Methods The refractive errors of the participants were assessed by an optometrist and were calculated using snellen’s chart and dioptres. The logistic regression was applied to assess the relationship between 2D:4D and myopia, as well as degree of myopia. Results The prevalence rate of myopia in the study population was 80.1%, with the prevalence in males (72.9%) being significantly lower than in females (87.4%) ( p =0.000). Moreover, female myopes were younger than male myopes ( p =0.005). In addition, 2D:4D on both hands in males were lower than for females (right hand: p =0.001, left hand: p =0.000). And there were only significant differences in left hand 2D:4D and mean 2D:4D between myopes and non-myopes in males, respectively ( p =0.04, p =0.024). Thelogistic regression analysis revealed there was significant association between myopia and 2D:4D in left hand in males( p >0.05). Conclusion These data defined key population variables necessary for expanding or targeting these analyses to other participant groups or study populations.