Prevalence and progression rate of myopia among medical students of internship course in Islamic Azad University, Tehran medical unit

This study was performed to evaluate the myopia prevalence, myopia progression, and various potential myopia risk factors in medical students’ final year (Internship period) at Islamic Azad University, Tehran unit. In this cross-sectional study, 240 medical students were selected through simple random sampling. The students, who spend Internship course at the university hospitals in the first term of 1383, were asked to complete a questionnaire designed to assess the prevalence of myopia, myopia Progression, and possible risk factors. The first part of questionnaire was completed by all participants and the second part was completed only by myopias. Myopia was defined on a per student basis at the mean spherical equivalent of equal to or less than – 0.5 diopters (D) at the end of medical school. Myopia progression defined as the difference between current myopia and spherical equivalent at the beginning of medical school. Among 240 students, the prevalence of myopia was 22.1%, myopia and astigmatism 29.2%, astigmatism 12.1%, astigmatism and hyperopia %2/9, hyperopia 1.7%. The prevalence of total refractive errors was 67. 9% and the prevalence of myopia found to be 51.3%. The mean equivalent sphere for the myopic student was – 2.28 D and the mean myopia progression during medical school was – 0.75 D. Myopia increased in 78.8% during medical college. Among myopic student 10% become myopic after the beginning of medical School. The mean age of onset of myopia was at 16 years of age. There was significantly statistical association between myopia and female gender, age of onset, positive myopia family history, and reading distance. Prevalence of myopia in our study was higher than worldwide prevalence. It may demonstrate the role of academic education and generally the reading required works as a risk factor for myopia.