Association of tinnitus with dementia
Reviewed by Madhup K Chaurasia

In this large case-controlled study, the authors have compared the presence of tinnitus prior to the diagnosis of dementia in the study group with those without dementia. Dementia patients were selected from the National Health Insurance group. The control group comprised randomly selected individuals matched 1:1 for age and sex. The patients with tinnitus were identified from International Classification of Diseases, Ninth Revision, Clinical Modification code 338.30 and it was important that the diagnosis of tinnitus occurred one year before the diagnosis of dementia was made. It was found that the dementia group had a higher percentage of cases with tinnitus, hearing loss, hypertension, diabetes, coronary artery disease, depression, hyperlipidaemia, alcohol dependence syndrome and thyroid disorders. After adjusting for the chronic diseases mentioned, cases under 65 years with tinnitus had a higher incidence of dementia and this was statistically significant. The authors have supported increased risk of dementia associated with tinnitus as being due to significantly diminished function in cognitive performance. These cognitive functions which are compromised are short-term memory, response time, processing accuracy and general learning tasks. Tinnitus may be connected to dementia by involvement of common pathways in the brain and the malfunction can be picked up by imaging. The authors contend that patients with tinnitus, who are 50–65 years of age, have 168% increased risk of being diagnosed with dementia. The risk cannot be ignored, considering tinnitus is often labelled idiopathic, incurable and left unmanaged.

Tinnitus and dementia risk: a nationwide population based case-control study.
Butt WWW, Wieland DR, Wang H, et al.
J LARYNGOL OTOL
2024;138(12):1170–5.