Abstract
Abstract: :
Purpose: To determine the clinical association between hemoglobin A1c (HbA1c) levels and intraocular pressure (IOP) in individuals with diabetic retinopathy. Studies have shown that elevated IOP is an important risk factor in the development of primary open–angle glaucoma. Our studies have indicated that elevated glucose levels in the aqueous humor may promote increased mRNA and protein expression of extracellular matrix components in the trabecular meshwork, possibly leading to elevated IOP. Methods: A retrospective data analysis was performed based on the Boston Medical Center eye clinic database and searched for individuals with the diagnosis of non–proliferative diabetic retinopathy (NPDR) and a corresponding HbA1c level measured 90 days before or 90 days after an IOP measurement. The database was searched from January 2000 to January 2003. Data from individuals were excluded if they had the diagnosis of glaucoma, were on or had ever been treated with IOP lowering medications, taking oral or topical steroids, did not have a HbA1c level measured within the 180 day time period, or did not have an IOP measured by Goldmann Tonometry. Approval to use data from human subjects was obtained prior to initiation of the research from the Boston University Institutional Review Board. Results: A total of 63 individuals met the inclusion criteria. When using 14.5mmHg as the widely accepted average IOP by Goldmann Tonometry, 25 individuals were identified with IOP < 14.5mmHg and an average HbA1c level of 7.92±0.9, while 38 individuals were identified with IOP ≥ 14.5mmHg with a corresponding average HbA1c of 8.92±2.2. A significant difference in the mean HbA1c level was observed between the two groups (P=0.037). Conclusions: These clinical findings indicate that elevated glucose levels in individuals with diabetes as represented by HbA1c values may be associated with an increase in IOP.
Keywords: intraocular pressure • diabetic retinopathy • clinical (human) or epidemiologic studies: risk factor assessment