Alzheimer’s Study Finds Symptom: Hearing Loss 6–10 Years Early
Finnish researchers say ringing in the ears and nerve-related hearing loss appeared more often in people who later developed early-onset Alzheimer's. The study, published in Alzheimer's and Dementia, found the gap six to 10 years before diagnosis.
Researchers at the University of Oulu and the University of Eastern Finland say tinnitus and hearing loss may be early warning signs of early-onset Alzheimer's disease, appearing up to a decade before major memory problems. An Alzheimer's study finds symptom patterns in the ear that show up well before diagnosis. The work was published in the journal Alzheimer's and Dementia.
The study looked at people diagnosed with Alzheimer's before the age of 65. It found they may experience distinct health complications as many as 15 years before diagnosis.
What the study found
Hearing difficulties stood out. These included ringing in the ears and nerve-related hearing loss. In the six to 10 years before a diagnosis, patients were twice as likely to report such problems, before clear cognitive and memory decline set in.
American healthcare researcher Neal K Shah discussed the findings in a YouTube video titled "10 Dementia Warning Signs You're Missing". He said that, out of 23 categories, "one and only one warning light flashed": ear, nose and throat conditions. Specifically, he pointed to tinnitus and bilateral sensorineural hearing loss, which means nerve-related hearing loss in both ears.
Shah gave the figures. Six to 10 years before diagnosis, he said, future patients had those ear conditions at a rate of 4.7% against 2.1% in controls. In the final five years the gap was 5.2% versus 2.9%.
Why ears and memory may be linked
Experts suggest two explanations. Early plaques in the brain may silently damage the region that processes sound. Or the effort of decoding sounds may leave the brain with less capacity for other thinking tasks.
Shah described the second idea as a battery with limited daily processing power, called cognitive reserve. When the inner ear struggles in a noisy restaurant or a meeting, he said, the brain "starts working overtime just to decode speech" and that "steals energy from your memory and thinking centers".
On the first idea, he said early Alzheimer's plaques and tangles can hit the auditory cortex, the brain's sound-processing system, years before they wreck memory.
What dementia is
According to the NHS, dementia is a broad term for a syndrome that causes progressive deterioration in brain function. It affects memory, thinking, language, behavior and the ability to carry out daily tasks.
The NHS says dementia is neither a natural nor an inevitable consequence of ageing. It occurs when diseases or injuries damage nerve cells in the brain, impairing how brain cells communicate.
Dr Asiya Maula, a GP and director at The Health Suite, said many people dismiss the earliest symptoms of Alzheimer's as simply getting older.
