Hearing loss

July 31, 2019

Association of Hearing Loss With Dementia

Chin-Mei Liu, PhD^1,2; Charles Tzu-Chi Lee, PhD¹

Author Affiliations Article Information

JAMA Netw Open. 2019;2(7):e198112. doi:10.1001/jamanetworkopen.2019.8112

Key Points Español  中文 (Chinese)

Question  What is the association of hearing loss with future incident dementia in the general population of Taiwan?

Findings  In this population-based matched cohort study of 16 270 participants, hearing loss was positively associated with incident dementia, especially in patients aged 45 to 64 years.

Meaning  Hearing loss is associated with a higher risk of dementia, and findings suggest that hearing protection, screening, and treatment may be used as strategies to mitigate this potential risk factor.

Abstract

Importance  Hearing loss (HL) may be a modifiable risk factor for dementia, and longitudinal studies are needed to examine the association of HL and dementia.

Objective  To investigate the association of HL with incident dementia in Taiwanese adults in the general population.

Design, Setting, and Participants  This population-based cohort study collected data from the National Health Insurance Research Database of Taiwan. Patients newly diagnosed with HL from January 1, 2000, through December 31, 2011 (n = 8135), constituted the exposed (HL) group. The HL group patients were matched by sex, age, residence, and insurance premium to individuals without HL (non-HL group) (n = 8135). Data were analyzed from January 1, 2000, to December 31, 2013.

Exposure  Hearing loss defined according to International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes.

Main Outcomes and Measures  Dementia classified according to ICD-9-CM codes.

Results  Of a total of 16 270 participants (9286 [57.1%] men; mean [SD] age, 65.2 [11.1] years), 1868 developed dementia. The dementia incidence rate in the HL group was higher than that in the non-HL group (19.38 [95% CI, 18.25-20.57] per 1000 person-years vs 13.98 [95% CI, 13.01-15.00] per 1000 person-years) during the follow-up period. In the fully adjusted multivariate Cox proportional hazards regression model applied for risk analysis, patients with HL had a significant risk of dementia (hazard ratio [HR], 1.17; 95% CI, 1.07-1.29; false discovery rate [FDR] P = .003). Subgroup analysis revealed that, among 3 age groups (45-64, 65-74, and ≥75 years), the group aged 45 to 64 years was associated with a risk of dementia (HR, 2.21 [95% CI, 1.57-3.12]; FDR P < .001). In sensitivity analysis, the presence of HL among those aged 45 to 64 years (HR, 1.40; 95% CI, 1.12-1.75; FDR P = .01) was associated with a risk of dementia.

Conclusions and Relevance  In this study, hearing loss was positively associated with a risk of dementia, especially in patients aged 45 to 64 years. Hearing protection, screening, and treatment may be used as strategies for mitigating this potential risk factor.