RESUMO
PURPOSE: Graves' disease (GD) and toxic nodular goiter (TNG) are associated with various comorbidities. However, it is unclarified whether TNG and GD without orbitopathy are associated with glaucoma. METHODS: This was a case-control study using record-linkage data from nationwide Danish health registers. 28,461 patients with GD and 17,283 with TNG were included. Each case was age and sex matched with four non-hyperthyroid controls and followed over a mean period of 8 years. Data on glaucoma was obtained by record linkage within the National Danish Patient Register and/or the Danish National Prescription Registry. Logistic and Cox regression models were used to assess the risk of glaucoma before and after the diagnosis of GD and TNG. RESULTS: Compared to controls, there was a significantly increased frequency of glaucoma in patients with GD (4.6 vs. 4.2%, P = 0.006) and in patients with TNG (6.2 vs. 5.7%, P = 0.003). Prior to the diagnosis of hyperthyroidism, the odds ratio (OR) for glaucoma was non-significant in GD (1.09, 95% CI: 1.00-1.18) but slightly increased in TNG (1.13, 95% CI: 1.02-1.24). However, in TNG the OR attenuated completely when only including patients without co-morbidity in the analysis (1.03, 95% CI: 0.93-1.14). After adjustment for pre-existing co-morbidity, the hazard ratio (HR) for glaucoma following GD and TNG was not significantly increased (HR 1.08, 95% CI: 0.98-1.18 and HR 1.10, 95% CI: 0.99-1.21, respectively). CONCLUSIONS: Neither prior to nor following the diagnosis of GD and TNG had any significant association with glaucoma.