Alzheimer's warning signs could emerge years before memory loss, study finds

A symptom linked to Alzheimer's disease could appear up to 10 years before memory problems become noticeable, according to new research reported by AOL.co.uk. Scientists found that people who develop Alzheimer's before age 65 may experience hearing problems years before receiving a diagnosis, including tinnitus, which causes ringing or buzzing in the ears, and hearing loss affecting both ears.

Researchers 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. 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.

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.

Separate coverage from Medical News Today describes Alzheimer's disease as the most common type of dementia, accounting for around 60% to 80% of cases in the United States. It typically starts at age 65 or older, though people can develop the condition in their 40s or 50s, and in rare cases in their 30s, known as early onset Alzheimer's disease. According to the Alzheimer's Association, a person with the condition will live 4 to 8 years after diagnosis on average, and may live as long as 20 years.