Catching signs of dementia early – before the main symptoms have started to show – means a bigger window of opportunity to study the progression of the condition, and to put support in place for those affected.
Past studies have looked at eye scans and blood tests as ways of doing this, for instance. Now new research suggests that worsening voice quality could also flag a higher chance of developing dementia in the years ahead.
The discovery comes from a team at the Drexel University College of Medicine in the US, who have published their findings in the Journal of Voice.
Across a total of 833,417 participants aged 50 and older, the researchers charted the relationship between getting a diagnosis of a voice disorder, hearing loss, or both, and the likelihood of developing cognitive impairment or dementia (including Alzheimer's), starting from a year after the voice and hearing assessments.
"We found the strongest link with dementia among patients experiencing a voice disorder and hearing loss," says Robert Sataloff, a professor and chair in Drexel's College of Medicine.
"Importantly, we found that those with a voice disorder and no hearing loss were at greater risk than patients who experience hearing loss only."
The results take some picking apart, because there were several comparisons going on, but the overall picture is that voice disorders – including changes in pitch, volume or clarity – might well predict cognitive decline in later life.
Participants with a voice disorder but no hearing loss were 58 percent more likely to develop cognitive problems or dementia later on, while for those with a voice disorder and hearing loss the chances more than doubled: 104 percent.
Those are comparisons against separate sets of matched controls without voice or hearing issues, however, not the same control groups.
For all voice disorder participants pooled together, with or without hearing loss, the increased risk came out at 29 percent. For hearing loss alone, it was 27 percent.
It's important to note that cause and effect isn't proven here: having a voice quality problem doesn't mean later brain health complications are inevitable, or that the voice issues are directly triggering cognitive decline, dementia, or Alzheimer's disease (the study didn't separate these three end results).
However, it's evidence that this could be another warning sign worth investigating. The association between hearing loss and dementia risk is already well established, and this study suggests voice quality problems are a similar indicator.
"It may be valuable for many of these patients to talk with an otolaryngologist who can arrange a cognitive assessment to help patients develop an appropriate care plan," says Sataloff.
The researchers have a few ideas about why this connection might exist. Voice problems are likely to reduce the amount of time spent talking, which in turn dials down the amount of healthy stimulation the brain gets.
What's more, difficulties in speaking – like hearing loss – tend to make people less likely to socialize, and we know social engagement is related to keeping dementia at bay.
"If you have a voice disorder that impacts how your voice sounds, or if it's painful when you attempt to talk or sing, it's only natural to participate less often in brain-supporting social or other engaging activities," says Sataloff.
The study team emphasizes that there's often help and treatment available for voice disorders, and that they may do your brain some good too – even if the underlying mechanisms between the two aren't quite clear yet.
Taking this research further could involve breaking down voice disorders by type and seeing whether treatment interventions affect the risk of cognitive decline or dementia over time.
"Future studies should explore whether specific voice disorder etiologies differentially predict cognitive decline," write the researchers in their published paper.
The research has been published in Journal of Voice.
This article was fact-checked by Rachel Garner and edited by Rebecca Dyer. While we pride ourselves on our process, we are only human. If you spot a mistake, please let us know.