Despite growing interest in hearing impairment as a potentially modifiable risk factor for dementia, the association is poorly understood. This has implications for whether treating hearing impairment can prevent or delay onset of dementia, as causation is not the only explanation for the association. In this editorial, we highlight how biases in research studies might account for the reported associations. We suggest future research using different study designs and novel biomarkers to help us overcome methodological limitations. This may allow us to determine the strength of the causal pathways linking hearing impairment to dementia, ultimately informing prevention and treatment strategies.
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