Despite a huge increase in the knowledge about disease mechanisms in various types of dementia in recent years, no curative treatment exists at present. Results from research on disease-modifying agents have been disappointing. This has led to an increased interest in other ways to reduce the prevalence of dementia. A recent report estimated that up to one third of dementia cases could be delayed or prevented by interventions directed at the most common risk factors. In the "Lancet commission on dementia prevention, treatment, and care", hearing impairment (HI) was identified as the potentially most important modifiable risk factor. Even though HI is considered an important modifiable risk factor, the evidence regarding the association between HI and dementia risk is still limited.