목적: Background Hearing loss is considered a major risk factor for dementia. We examined the effect of hearing aid use on dementia incidence in a hearing-impaired population in a nationwide population. 방법:Methods This was a retrospective, longitudinal, cohort study of South Korean national claims data for individuals newly registered with hearing disabilities (better ear ≥40dBHL with worse ear ≥ 80dBHL, or better ear ≥60dBHL) between 2004 and 2008. The hearing aid cohort comprised individuals who received hearing aid subsidies from the National Health Insurance within a year from disability registration. The comparison cohort comprised individuals without a record of a hearing aid claim during the study period after 1:1 matching for audiologic and sociodemographic factors with the hearing aid cohort. The occurrence of dementia was followed up until 2018 and risk analysis was performed. 결과:Results Each cohort comprised 8,780 individuals. Overall incidence of dementia in the hearing aid and comparison cohorts was 156.0 and 184.5 per 1,000 persons, respectively (incidence rate ratio=0.85, 95%CI 0.79- 0.91). In multivariable analysis, hearing aid use (HR=0.75,95%CI 0.70- 0.81) and above-median income attenuated the risk of dementia while age, female gender, dwelling in a rural area, hypertension, ischemic heart disease, head trauma, diabetes, alcohol-related diseases, cerebrovascular diseases, and depression increased the risk of dementia. 결론:Conclusions Dementia incidence in individuals with hearing disabilities was lower in hearing aid users than non-users. Hearing rehabilitation with hearing aids should be encouraged for individuals with hearing loss.