Alzheimer’s disease increasingly clarified
There is growing awareness and recognition of Alzheimer’s as a disease, rather than a part of normal aging. So thinks Professor Kaj Blennow of the University of Gothenburg, a leading researcher in the field. “Alzheimer’s Day is one way of building further on this," he says.
World Alzheimer's Day falls on September 21 annually. In various ways, attention is focused on the disease in Sweden and abroad, throughout the month. Alzheimer’s is our most common form of dementia, and the number of sufferers is rising.
Typical symptoms of Alzheimer's disease involve impacts on recent memory, language, thinking, concentration, and perception of time. Anxiety and depressive symptoms are also common, which also affect other people in the patient’s vicinity. Dementia is sometimes described as a “family illness.”
Dementia diseases are caused by parts of the brain being affected and impaired. The problems that arise depend on which part of the brain has suffered these effects. In Alzheimer’s, nerve cells in the memory center of the brain deteriorate at an early stage of the disease.
Tests in primary care
In Alzheimer’s, the protein beta-amyloid forms harmful clumps (“amyloid plaques”) in the brain. In addition, another protein, tau, changes and forms small, interlacing threads called tangles inside the nerve cells, which also contributes to the degeneration of these cells. Measuring these changes by means of biomarkers is a strong area of research at the University of Gothenburg.
Kaj Blennow, Professor of Neurochemistry at the Faculty of Medicine, Sahlgrenska Academy, and Chief Physician at Sahlgrenska University Hospital, comments.
“The most exciting thing we’ve worked on is developing methods for measuring phospho-tau, the protein found in tangles in Alzheimer’s. These tests work very well and can show, with great reliability, whether a patient has tangles and thus Alzheimer's. The idea is that they could serve as screening tests earlier on — in primary care, for example.”
By screening he means not extensive testing of asymptomatic groups, but testing of people who seek medical care because they have problems with, for example, their memory and speech ability.
“There, the tests could be used to see which patients can be referred to specialist clinics for more detailed investigation, and hopefully soon for treatment as well,” Blennow says.
Development of drugs to treat Alzheimer’s has brought both hopes and disappointments. This applies to the drug aducanumab, a monoclonal antibody, that was rapidly approved by the U.S. Food and Drug Administration (FDA) in summer 2021 and is now being evaluated by the equivalent EU organization, the European Medicines Agency (EMA).
The clinical benefit of aducanumab — that is, whether it alleviates the symptoms — has not yet been established, but it does reduce formation of amyloid plaques, one of the underlying processes of the disease.
“The quantity of plaques decreases significantly, and aducanumab is therefore termed ‘disease-modifying.’ This is a huge step forward, and there are several similar immunotherapies against amyloid that are in the final phase of testing and have already shown similar, very promising effects,” Blennow concludes.