Aging
Estimating the causal effect of hearing impairment on risk of dementia over 18 years in US older adults: A target trial emulation Yixun Ke* Yixun Ke Ke Ke Ke Ke Ke Ke Ke Ke Ke Ke Department of Epidemiology, UCLA Fielding School of Public Health
Hearing impairment is a potential modifiable risk factor for dementia. However, the long-term effects using rigorous methods have remained understudied. We estimated the effect of baseline hearing impairment on the risk of developing dementia among older adults in the United States using a target trial framework over up to 18 years of follow-up. We used data from the Health and Retirement Study (HRS) 1998-2016, including adults aged ≥50 years without dementia at baseline. We considered individuals to have hearing impairment if they rated their hearing quality as fair or poor at baseline, and to not have hearing impairment if they rated it as excellent, very good, or good. Incident dementia was derived using the Langa-Weir classification algorithm. We used pooled logistic regression and the parametric g-formula with time since baseline as a discrete-time scale to estimate adjusted survival and adjusted effects on dementia had all participants started with vs without the hearing impairment at baseline, accounting for censoring. We adjusted for demographics, health and lifestyle covariates. We used multiple imputation to address missingness in exposure and covariates and bootstrapping was used to estimate the 95% CIs. On average, if everyone in the population had baseline hearing impairment, there would be 2.02 (95% CI: 1.16, 2.88) excess dementia cases out of 100 individuals compared to if everyone did not have baseline hearing impairment. Similarly, the average risk of dementia if everyone in the population had baseline hearing impairment would be 1.38 (95% CI: 1.19, 1.56) times that if everyone did not have baseline hearing impairment. In this study, we found that baseline hearing impairment increased the risk of dementia over 18 years of follow-up. These findings support early intervention on hearing impairment as a potentially important population-level strategy for dementia prevention.
