Initiation of Hearing Aids Use and Incident Dementia Among Mid-to-late Life Adults: The Health and Retirement Study 2010-2018.

Background and objectives: Hearing aids may reduce the risk of dementia among individuals with hearing loss. However, no evidence is available from randomized controlled trials (RCTs) on the effectiveness of hearing aids use in reducing incident dementia. Using target trial emulation, we leveraged an existing longitudinal cohort study to estimate the association between hearing aids initiation and risk of dementia.

Research design and methods: The Health and Retirement Study was used to emulate target trials among non-institutionalized participants aged ≥50 years with self-reported hearing loss, without dementia at baseline, and without use of hearing aids in the previous 2 years. Intention-to-treat analysis was conducted to estimate the risk of dementia associated with hearing aids initiation vs controls who did not initiate hearing aids. Pooled logistic regression models with inverse-probability of treatment and censoring weights were applied to estimate risk ratios, and 95% confidence intervals were calculated using 1000 sets of bootstrapping.

Results: Among 2314 participants (328 in the intervention group and 1986 in the control group; average age: 72.3 ± 9.7 years, 49% women, and 81% White), after 8 years of follow-up, risk of dementia was significantly lower among individuals who initiated hearing aids (risk difference (RD): -0.05, 95% confidence interval (CI): -0.08, -0.01). A lower risk was observed particularly among adults aged 50-74 years, men, and individuals with cardiovascular disease.

Discussion and implications: Hearing aids use was associated with a significant reduction of incident dementia. Future interventional studies are needed to further assess the effectiveness of hearing aids in preventing dementia.