Endocrine Abstracts

Introduction: A significance of chronic hyperglycaemia related to the rising intraocular pressure are discussed in the previous studies. The purpose of the present study was to investigate changes of intraocular pressure induced by acute changes of glucose levels during oral glucose tolerance test in non-diabetic subjects.

Methods: Fifty-one individuals who were needed to be screened for diabetes, were scheduled for oral glucose tolerance test according to the World Health Organization criteria. Biochemical parameters associated with metabolic syndrome, insulin resistance (HOMA-IR) and systolic and diastolic pressure were also measured. Complete ophthalmologic examination was performed before the test. The inclusion criteria were having a normal intraocular pressure (<21 mmHg), and having no eye disease, no ophthalmic surgery or no glaucomatous optic nerve appearance. During the test, intraocular pressure was measured by using rebound tonometry (ICARE) two times at the fasting state and at first and second hours after oral glucose administration.

Results: The mean age of the patients was 46.24±11.31 years. The mean BMI was 29.63±5.25 kg/m². The median fasting glucose and intraocular pressure for right was 100 mg/dl (91.250–105.750) and 17 mmHg. The median glucose and intraocular pressure level for right eye in the first hour and in the second hour in OGTT were 153 mg/dl (123.5–190.5), 18 mmHg (14–22) and 117 mg/dl (92.25–140) and 18 mmHg (14–20.75) respectively. The intraocular pressure right eye were significantly higher in the first hour compared to the fasting values (P<0.05).

Conclusion: The relation between diabetes mellitus and glaucoma has been addressed in many studies with no clear underlying mechanisms. In our study on healthy non-diabetic individuals, acute hyperglycaemia has found to have a positive relationship with intraocular pressure, suggesting that acute hyperglycaemia may represent a possible mechanism.