The Relation between High Myopia and Diabetic Retinopathy

Abstract Background: The prevalence of myopia is growing world-wide, and myopia is becoming a major epidemiological problem. A higher prevalence of myopia has been observed in people with diabetes compared with people without diabetes and poorer glycaemic control considered to be a risk factor. Aim of Study: To determine the relation between High Myopia and Diabetic Retinopathy and to detect whether high Myopes are self-protected against diabetic changes and diabetic retinopathy or not. Patients and Methods: The study included 140 eyes from 96 diabetic patients recruited from National Institute of Diabetes and Endocrinology in the Ophthalmic Clinic. They were classified according to the refractive status into four groups: Emmetropia (0.00 to –0.50 {DS}), Low Myopia (–0.50 DS to –3.0 DS), Moderate Myopia (3.00 DS to –5.00 DS) and High Myopia (more than –5.00 DS). High myopia (70 eyes of 41 patients), moderate myopia (10 eyes of 7 patients), low myopia (39 eyes of 29 patients) and emmetropia (21 eyes of 19 patients). Results: Total male patients represent 52.08% and females 46.92% in our study. There were statistically significant difference between groups as regard mean of refraction. Mean of refraction represented by Spherical equivalent among groups (Emmetrope, high myope, mild myope and moderate myope) was (2.08±0.495, 14.94±3.73, 3.23±0.642, 5.505±0.41) respectively. From our results the frequency of NPDR totally was 70 eyes (50%) and no DR was 70 eyes (50%). All high myopic eyes (70 eyes) showed no DR and all eyes of other groups which are totally (70 eyes) showed DR with its different grades. All high myopic eyes (70 eyes of 41 patients) had no DR in their fundus photograph while (low myopic, moderate myopic eyes and emmetropic eyes (39, 10, 21 eyes) respec-tively showed DR with its different grades: Low myopic eyes (39 eyes of 29 patients) showed moderate NPDR, the moderate myopic eyes (10 eyes of 7 patients) showed mild NPDR and the emmetropic eyes (21 eyes of 19 patients) showed severe NPDR. There were statistically significant difference between groups as regard severity of diabetes in which p-value <0.005. From our results as the degree of myopia increases the severity of DR decreases.
Conclusion: There is a protective role for high myopia against DR.