Study of the Types of Refractive Disturbances Obseved during Hyperglycemia in Humans

Introduction: Refractive disturbances have been observed during hyperglycemia. However, there remains controversy as to the types of disturbances that it induces. Objective: To determine the types of refractive disturbances observed during hyperglycemia in humans. Population and Methods: This was an observational and cross-sectional study with an analytical purpose conducted from July to November 2021. Emmetropia, hypermetropia, and myopia as well as blood glucose levels were compared between day 0 (D0) and day 30 (D30) after initiation of hypoglycemic therapy in 222 people (444 eyes) with recently discovered hyperglycemia (Chi-2; p < 0.05). Results: At D0, the mean of blood glucose was 18.1 mmol/L ± 8.2 vs 6.9 mmol/L ± 3.0 at D30 (p = 0.001). At day 0, 80% (n = 355) of eyes were hypermetropic compared to 73.9% (n = 328) at D30 (p = 0.02). At D0, 14.2% of eyes (n = 63) were myopic compared to 11.3% (n = 50) at D30 (p = 0.02). Refraction improved from 0.75 to 1.5D for 34.5% (n = 18) of hypermetropic eyes and 10.2% (n = 2) of myopic eyes. Conclusion: Our results show that hypermetropia is the most common ametropia during hyperglycemia. Moreover, these data suggest that the normalization of blood glucose improves refraction.