Hearing problems such as tinnitus and hearing loss could appear up to 10 years before memory difficulties become noticeable in people who develop Alzheimer's disease before the age of 65, according to new research.
Scientists from the University of Oulu and the University of Eastern Finland examined the medical records of 407 people diagnosed with early-onset Alzheimer's disease. They compared their records with those of more than 4,000 people of a similar age and sex who did not have a neurodegenerative disease.
Study Findings on Hearing Conditions
The study looked at health conditions recorded up to 15 years before an Alzheimer's diagnosis. Between six and 10 years before diagnosis, 4.7% of those who later developed Alzheimer's had recorded ear, nose and throat conditions. That compared with 2.1% of people in the comparison group, meaning these conditions were more than twice as common among those who went on to develop the disease.
Researchers also found that other health problems became more common in the five years before diagnosis. These included depression, dizziness, headaches, thyroid problems and epilepsy.
Implications and Next Steps
However, having tinnitus or hearing loss does not mean someone will develop Alzheimer's. Hearing problems are common and can be caused by several different conditions.
Alzheimer's Society says hearing loss during middle age has been linked to an increased risk of dementia, although the reasons behind this are still being studied. One theory is that hearing difficulties make the brain work harder to process sounds and conversations.
The NHS says early signs of dementia can also include memory loss, difficulty concentrating, struggling to follow conversations and becoming confused about time or place. Anyone experiencing persistent hearing problems should speak to their GP or arrange a hearing test.
