Age-related hearing loss and dementia: a 10-year national population-based study.

Abstract

Age-related hearing loss (ARHL) is postulated to affect dementia. Our study aims to investigate the relationship between ARHL and the prevalence, and 10-year incidence of dementia in the Taiwan National Health Insurance Research Database (NHIRD). We selected patients diagnosed with ARHL from the NHIRD. A comparison cohort comprising of patients without ARHL was frequency-matched by age, sex, and co-morbidities, and the occurrence of dementia was evaluated in both cohorts. The ARHL cohort consisted of 4108 patients with ARHL and the control cohort consisted of 4013 frequency-matched patients without ARHL. The incidence of dementia [hazard ratio (HR), 1.30; 95% confidence interval (CI 1.14-1.49); P = 0.002] was higher among ARHL patients. Cox models showed that being female (HR, 1.34; 95% CI 1.07-1.68), as well as having co-morbidities, including chronic liver disease and cirrhosis, rheumatoid arthritis, hypertension, diabetes mellitus, stroke, head injury, chronic kidney disease, coronary artery disease, alcohol abuse/dependence, and tobacco abuse/dependence (HR, 1.27; 95% CI 1.11-1.45), were independent risk factors for dementia in ARHL patients. We found ARHL may be one of the early characteristics of dementia, and patients with hearing loss were at a higher risk of subsequent dementia. Clinicians should be more sensitive to dementia symptoms within the first 2years following ARHL diagnosis. Further clinical studies of the relationship between dementia and ARHL may be necessary.