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Pioneering research on working-age memory disorders is conducted in Oulu

 

Memory disorders are seen as diseases of the elderly. One third of those over 85 years of age suffer from a memory disorder, most commonly Alzheimer’s disease. However, a memory disorder can manifest itself much earlier on, at the age of 50 to 60.

“That is to say at the prime working age,” says Dean and Professor of Neurology Anne Remes of the Faculty of Medicine of the University of Oulu. She leads a research group that conducts pioneering research on working-age memory disorders at the global level.

Anne has esearched the topic since the 1990s. At that time, the diagnostics of memory disorders advanced in leaps and bounds and a memory outpatient clinic was established at the Oulu University Hospital.

“I became especially interested in the working-age patients suffering from memory disorders whose clinical picture and disorder spectrum differ from those who are impacted later in life,” says Anne. She has focused on studying frontotemporal lobar degeneration, which is one of the three most common progressive memory disorders along with Alzheimer’s disease and Lewy body disease.

“The significance of heredity in memory disorders is a key research question, and a lot is going on in the sphere of genetic research.”

In November, Professor Anne Remes received the silver badge of honour of the Memory Association of the Oulu Region as a recognition of her long-term work in the field of studying memory disorders. Photo: Seija Leskelä

Overpowering and awful frontotemporal lobar degeneration

There are about 10,000 patients in Finland who have been diagnosed with a memory disorder under the age of 65. Less than 40% of them suffer from Alzheimer’s disease, while the share of Alzheimer’s disease among people aged over 85 is approximately 70%.

The share of frontotemporal lobar degeneration is high among those impacted at the working age, approximately 20%.

The symptoms of frontotemporal lobar degeneration are similar to early-stage mental disorders. The patient may be apathetic or manic, and there may be changes in personality: a gentle middle-aged person can become an aggressive swearer. Diagnosis is difficult, as the early-stage changes in the brain do not show in brain scans.

Just recently, Anne’s research group made a major discovery related to the diagnostics of frontotemporal lobar degeneration: blood neurofilament concentrations are significantly higher among those suffering from degeneration than those who are mentally ill. In the future, diagnosis will be facilitated by a simple blood test.

Frontotemporal lobar degeneration has an awful reputation and not without reason.

“The average progression of the disease from diagnosis to death is 8–10 years. The disease cannot be retarded or cured. However, the symptoms can be treated and thereby give the patient more quality of life,” says Anne Remes.

Genetic defects, risk genes, bad lifestyle choices or just bad luck?

There are genes associated with frontotemporal lobar degeneration that cause the disease with great probability. The C9orf72 repeat mutation is the most common of them. There are several hundred families in Finland that have this genetic defect.

From among the frontotemporal lobar degeneration patients examined at the Oulu University Hospital, nearly one in three has been diagnosed with this genetic defect that also causes the motor neurone disease known as ALS. It is not yet known why the same genetic defect causes frontotemporal lobar degeneration to others and ALS to others.

“Then, there are many risk genes that do not directly cause frontotemporal lobar degeneration, but increase the risk of getting it,” says Anne.

Alzheimer’s disease has its own risk genes. The most common of these is the APOE4 allele that is also associated with a high blood cholesterol level.

“If you get the APOE4 allele from both parents, the probability of getting the disease by the age of 80 is 50%.”

Among young persons diagnosed with memory disorders, these risk factors play a minor role; the cause can usually be found in the genes.

There are also genes whose carriers become ill with Alzheimer’s disease at a young age, as early as 40. In Finland, there are perhaps only about ten families that carry this gene.

Non-genetic risk factors include high cholesterol, obesity, smoking, high blood pressure, diabetes, lack of physical exercise and limited use of the brain.

Among young persons diagnosed with memory disorders, these risk factors play a minor role; the cause can usually be found in the genes. However, there are also patients who do not carry a hereditary burden and who live healthy and who still become ill with a progressive memory disorder.

“It’s just bad luck in the lottery of life.”

Gene therapy to help

Genetic study of patients suffering from memory disorders is a topical and important ethical issue. With respect to the C9orf72 genetic defect, genetic tests are carried out on patients, but not for the identification of risk genes. The genetic test benefits diagnostics, but discovering a genetic defect is a difficult situation for the patient’s close relatives. Symptomless siblings have a 50% risk of being a carrier of the gene. Siblings may want genetic tests done, but symptomless persons are not tested.

Routine genetic testing would open a Pandora’s box – could you get an insurance policy or a job if you were to have this genetic defect?

“Genetic studies give a lot to science, but they are difficult issues for individuals when there is no curative treatment.”

It may be a different case in the future. Therapeutic studies are already under way in the case of the C9orf72 genetic defect.

“I believe that this genetic defect can be corrected with gene therapy in the years to come. The patient will be implanted with a gene string through blood circulation that will fix the defective gene. This is already being tested at the cell level, but there is still a long way to go before an actual treatment is achieved,” says Anne Remes.

When are memory problems to be taken seriously?

Memory disorders frighten people, at least judging by tabloid health articles: almost every week they include information about a diet or lifestyle that prevents memory disorders or about other ways to avoid them.

Everyone occasionally forgets their keys at home, drive past a familiar crossing or forget the most important item on the shopping list. When is forgetfulness a cause for concern?

“If you forget things every week, you should stop to think about it,” says Anne.

A memory disorder is quickly diagnosed among those who do information-intensive work, as oversights and mistakes come up mercilessly in the work community. It is, however, worth remembering that also sleep deprivation, stress and depression can cause memory disturbances.

If you are concerned about your memory disturbances, you should contact occupational health care or your local health centre where the situation can be mapped with memory tests. If the difficulties in remembering things cannot be explained with stress or other treatable causes, the patient will be referred to a memory outpatient clinic.

Can you try to protect yourself from memory disorders?

“I can list the same things that also prevent many other diseases. Use alcohol very moderately, do not smoke and avoid excessive stress. Eat healthily. Keep your weight, cholesterol level and blood pressure in check. Exercise and sleep enough. Pleasure, social relations and appropriate brain activation are also important for brain health,” says Professor Anne Remes.

Text: Satu Räsänen

Last updated: 13.1.2020