How to distinguish Alzheimer's disease from other types of dementia?
A new method developed by Italian researchers from the University of Brescia under the guidance of Dr. Barbara Borroni allows differential diagnosis of Alzheimer's disease and frontotemporal dementia - two types of senile dementia with almost identical symptoms.
Until recently, frontotemporal dementia was considered a rare disease, but today it is considered that it accounts for 10-15% of cases of dementia. Quite often, due to the wide range of symptoms, this disease is initially misdiagnosed as a psychiatric problem, Alzheimer's disease or Parkinson's disease. As a rule, it affects people in the age range from 45 to 65 years and is characterized by severe behavioral changes and speech disorders. Despite the lack of effective therapy, it is very important to establish an accurate diagnosis in order to help the patient control symptoms and avoid unnecessary treatment.
According to Dr. Borroni, this can be a very difficult task. Modern methods of differential diagnosis of neurodegenerative diseases require the use of expensive brain tomography or invasive lumbar punctures requiring the insertion of a thick needle into the spinal canal.
As an inexpensive non-invasive alternative, the authors proposed using a technology known as transcranial (transcranial) magnetic stimulation. It consists in placing a large electromagnetic coil on the scalp that emits electrical impulses stimulating nerve cells.
In their study, the authors included 79 patients with suspected Alzheimer's disease, 61 patients with suspected frontotemporal dementia and 32 people of the same age who did not have dementia.
The use of transcranial magnetic stimulation allowed them to measure the brain's ability to conduct electrical signals along various neural circuits. As a result of the analysis of the collected data, it was found that patients with Alzheimer's disease predominantly experienced problems with one type of neural circuits, whereas patients with frontotemporal dementia suffered from another type.
In subsequent experiments, the researchers were able to differentiate frontotemporal dementia from Alzheimer's disease with 90% accuracy, Alzheimer's disease from the normal state of the brain with 87% accuracy and frontotemporal dementia from the normal state of the brain with 86% accuracy. The accuracy of the results was almost the same when examining patients with only mild forms of diseases. It was also comparable with the accuracy of the examination results using positron emission tomography and lumbar functions of cerebrospinal fluid.
The study had a number of limitations, including the fact that the specialists who conducted the examination knew which of the participants were in the control group, but they were not informed about which patients had Alzheimer's disease and which had frontotemporal dementia. In addition, the diagnoses of dementia were not confirmed by the results of a post-mortem autopsy.
The authors note that the confirmation of the results in a larger study will allow the implementation of their proposed approach into clinical practice. Rapid and non-invasive differential diagnosis of age-related neurodegenerative diseases will significantly improve the quality of medical care for patients. Unfortunately, these diseases are incurable, but their timely diagnosis allows you to choose the right treatment and mitigate the symptoms.
Article by Alberto Benussi et al. Transcranial magnetic stimulation distinguishes Alzheimer's disease from frontotemporal dementia published in the journal Neurology.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of the American Academy of Neurology: Is It Alzheimer's Disease or Another Dementia?
28.07.2017