Abstract
Abstract: :
Purpose: To assess whether thyroid disease is associated with open-angle glaucoma (OAG) in an older population, after accounting for other glaucoma risk factors. Methods: The Blue Mountains Eye Study examined 3654 people, 82% of a defined population, aged 49+ years, west of Sydney, Australia. OAG was diagnosed when glaucomatous visual field defects matched optic disc cupping and rim thinning, independently of intraocular pressure. Interviewers ascertained history of thyroid disease, including thyroid activity at time of diagnosis and treatment modality. Results: A history of thyroid disease was reported by 8.9% of participants in this population, including 4.0% with ‘hypothyroidism', and 2.0% with ‘hyperthyroidism' at diagnosis. Ever use of thyroxine was documented in 5.5% of subjects, with current use reported by 4.0%, and a history of past thyroid surgery by 2.5%. A thyroid disease history was given 5-fold more frequently by women than men, p=0.001, but no age-related increase was found. Current thyroxine users were slightly older (68.1 years) than subjects without thyroid disease (66.0 years), p=0.006. The overall OAG prevalence was 3.0% and was higher in subjects with (4.6%) than in those without thyroid disease(2.8%). This relationship was borderline, odds ratio (OR) 1.6, 95% confidence interval (CI) 0.9-2.9, after adjusting for glaucoma risk factors including age, sex, hypertension, glaucoma family history, pseudoexfoliation, myopia and diabetes. Subjects reporting current thyroxine use (6.8%) had more than double the OAG prevalence than those reporting no history of thyroid disease (2.8%), multivariate-adjusted OR 2.1, CI 1.0-4.4. The glaucoma prevalence was also significantly higher in subjects who reported past thyroid surgery (6.5%), multivariate-adjusted OR 2.5, CI 1.0-6.2. After amalgamating all thyroid disease subgroups, a statistically significant association was found between thyroid disease and ‘low-pressure’ glaucoma in multivariate-adjusted analyses, OR 3.1; CI 1.4-7.0. There were no differences in mean IOP or in the prevalence of ocular hypertension between the groups. Conclusions: Current use of thyroxine was independently associated with a two-fold increased OAG prevalence after adjustment for other glaucoma risk factors. This report suggests the possibility that thyroid disease (hypothyroid state) may be a systemic risk factor for glaucoma, of modest magnitude, similar to that reported for diabetes.
Keywords: clinical (human) or epidemiologic studies: ris • clinical (human) or epidemiologic studies: pre