Metabolic Syndrome: A Risk Factor for Normal Tension Glaucoma?

Abstract

Introduction: To determine whether normal tension glaucoma (NTG) is associated with metabolic syndrome and to evaluate which components of metabolic syndrome are related to NTG. Methods: This study included 18,244 Korean adults aged 40 years or older who underwent health checkups including fundus photography and intraocular pressure measurements between September 2010 and August 2011. For NTG diagnosis, all participants with findings suggestive of glaucoma completed a comprehensive glaucoma evaluation, including applanation tonometry, gonioscopy, stereoscopic disc photography, retinal nerve fiber layer photography, and standard automated perimetry. The National Cholesterol Education Program Adult Treatment Panel III guideline was used to characterize metabolic syndrome. Results: Of the 18,244 participants, 3636 (19.9%) had metabolic syndrome and 300 (1.6%) were diagnosed with NTG. The presence of metabolic syndrome was associated with NTG, which had borderline significance by logistic regression analysis (OR, 1.28

P=0.0667). Of the individual components of metabolic syndrome, hypertension and impaired glucose intolerance (IGT) were found to be significantly associated with NTG (OR, 1.53

P=0.0005 and OR, 1.47

P=0.0063). Individuals with both of these conditions showed an increased association with NTG (OR, 2.42

P=0.0001). None of the other components of metabolic syndrome were significantly associated with the incidence of NTG. NTG was positively associated with the number of metabolic syndrome components (OR, 1.10

P=0.0398). Conclusions: Of the metabolic syndrome components, hypertension and IGT contributed to an increased risk of NTG. These findings suggest that components of metabolic syndrome play an important role in the pathogenesis of NTG.