On July 31, 2024, the Lancet Commission on dementia prevention, intervention, and care released their latest report. The full report can be read here. This report builds on the findings from their 2020 publication, which identified hearing loss as a significant modifiable risk factor for dementia, accounting for 7% of the variance.
In the 2020 report, 12 risk factors were highlighted, including:
The 2024 report adds two more risk factors: high cholesterol and untreated visual loss. Collectively, these 14 factors account for 45% of the variance in dementia cases, suggesting that nearly half of all dementia cases could theoretically be prevented by addressing these risk factors.
When focusing on hearing loss, it's important to note that it, along with depression (3%) and social isolation (5%), accounts for 14% of the modifiable risk factors. An intriguing finding in the 2024 report is the correlation between the ability to hear in noise and the likelihood of developing dementia. The greater the difficulty in hearing in noisy environments, the higher the risk of dementia.
This finding has significant implications for hearing aid fittings. It's crucial to consider a patient's ability to hear in noise when selecting amplification and recommending accessories. For instance, the Multi-Mic+ (a versatile portable microphone that connects directly to hearing aids and helps patients hear in a variety of situations) should be recommended when hearing aids alone do not provide sufficient benefit in noisy environments.
To ensure that a patient's ability to hear in noise is adequately addressed, measuring Signal-to-Noise Ratio (SNR) loss should become a standard part of the hearing evaluation. I recommend using the QuickSIN test, which is performed under earphones individually in each ear and takes less than one minute per ear. The result is the SNR loss, which helps in choosing the right Beltone hearing aid.
For example, the Beltone Serene 17 offers an SNR improvement of 8.5 dB, the Beltone Serene 9 provides an improvement of 4.5 dB, and the Beltone Serene 5 offers an improvement of 3 dB. While all hearing aid users will benefit from the level 17 technology for speech in noise, those with an SNR loss greater than 5 dB should consider using the Multi-Mic+. This accessory, with its hearing-in-noise benefit of up to 20 dB, can significantly improve the patient’s ability to hear in noisy environments.
In conclusion, the 2024 Lancet report underscores the importance of addressing hearing loss as a modifiable risk factor for dementia. By carefully considering a patient's ability to hear in noise and selecting the appropriate hearing aids and accessories, we can make a meaningful impact on their overall cognitive health.
References: Livingston, Gill et al. "Dementia prevention, intervention, and care: 2024 report of the Lancet standing Commission." The Lancet, Volume 404, Issue 10452, 572 - 628.
Dr. Christensen leads Global Audiology for GN Hearing, which is part of the Research and Development department based in Ballerup, Denmark. Global Audiology is responsible for all of GN Hearing’s corporate audiology activities related to new product development and launch, including clinical trials, regulatory activities, audiology support to product marketing, and training and education to subsidiaries world-wide.
Dr. Christensen holds an adjunct faculty appointment at Northwestern University in Chicago. She has presented well over 250 talks around the world and has many publications, including book chapters on hearing aid technology. In 2012, Dr. Christensen received the Leader of the Year award from GN Hearing for her outstanding contributions to the company. In 2015, she received the Distinguished Alumna Award from the Department of Speech and Hearing Sciences at Indiana University where she received both her M.S. and Ph.D.
