Associations between tinnitus and glaucoma suggest a common mechanism: A clinical and population-based study

The purpose of this study was to determine if there is an association between tinnitus and glaucoma. We tested this by first completing a clinic-based cross-sectional questionnaire study in which we sent a series of tinnitus-related questions to glaucoma patients and healthy subjects, and then followed up with a large population-based cross-sectional study in which glaucoma and tinnitus were also assessed by questionnaire. For the clinical study, we received 209 responses from glaucoma patients and 109 responses from healthy subjects (primarily the spouses of the patients). For the population-based study, we evaluated 79,866 participants. Logistic regression models were used to test the relationship between glaucoma and tinnitus; the clinical study analysis was adjusted for age, gender, BMI, hypertension, and diabetes and the population-based study was adjusted for these same variables with the addition of socioeconomic status and subjective hearing loss. For the clinical study, glaucoma patients had an 85% increase in odds for tinnitus (adjusted OR 1.85, 95% CI 1.10 to 3.05). The effect did not depend on pretreatment intraocular pressure, and the associated symptoms were not pulsatile in nature. For the population-based study, glaucoma patients had a 19% increase in odds for tinnitus (adjusted OR 1.19, 95% CI 1.02 to 1.40). Overall, our results suggest that those with glaucoma are more likely to have tinnitus than those without glaucoma. These results provide hypotheses for a mechanism involved in both tinnitus and glaucoma. One possible mechanism could be vascular dysregulation due to impairment of nitric oxide production.