Dementia is a so-called dementia syndrome, i.e. an interplay of several, different, simultaneously occurring symptoms caused by a progressive loss of brain tissue (particularly affected is the cerebral cortex and the tissue immediately below the cortex). Thus, dementia can be considered a neurological disease pattern. The symptoms must persist for at least 6 months before a diagnosis can be made.
In summary, one speaks of a decline in higher cortical functions, i.e. cognitive (e.g. perception, attention, memory, learning etc.) and intellectual abilities, which in most cases ends inexorably in a personality breakdown and a loss of everyday competence (however, few forms of dementia are reversible, i.e. curable). Three major groups of dementia diseases will be distinguished, which can be divided into vascular dementias (multi-infarction syndrome, after micro-vascular changes), neurodegenerative dementias (Alzheimer’s disease, frontotemporal dementia, Lewy body dementia) and so-called mixed forms, based on the underlying causes.
Cause
The cause of vascular dementia is usually a single or multiple, smaller or larger cerebral infarction or cerebral haemorrhage, which destroys and destroys brain tissue. These infarcts or bleedings can be caused, for example, by a long-lasting, badly adjusted high blood pressure, thromboses or embolisms in brain vessels, ruptures of brain vessels. The forms of dementia that occur as a result of neurodegenerative diseases, i.e. the hereditary, progressive destruction of nerve cells, are all caused by deposits of defective protein cleavage products. However, the various forms of dementia (Alzheimer’s disease, frontotemporal dementia, Lewy body dementia) differ in the respective protein cleavage product and in the brain region where these deposits are located. In addition, various metabolic and hormonal disorders (vitamin B12 deficiency, hypothyroidism, brain involvement in liver or kidney failure), intoxication (alcohol, carbon monoxide, solvents) or infection (AIDS, prion disease, Creutzfeldt-Jakob disease) can also cause dementia symptoms.
Symptoms
At the beginning of the disease there is usually a gradual loss of memory and short-term memory, so that the affected persons are increasingly unable to absorb, store and reproduce new information. Only later, when the dementia disease is in an advanced stage, do long-term memory disorders appear, so that events that have occurred longer ago can be forgotten and skills and abilities acquired over the course of a lifetime can be lost. Furthermore, the forms of dementia can be characterised by disorders in orientation (first temporal, then local and then personal), in thinking (slowed down, flow impeded), in recognition, in speech, in arbitrary movements and changes in personality (increased instability and irritability, social withdrawal, paranoid features).
In general, however, the symptoms must persist for more than 6 months in order to diagnose a dementia syndrome. Furthermore, the forms of dementia can be characterised by disorders in orientation (first temporal, then local and then personal), thinking (slowed down, flow impeded), recognition, language, arbitrary movements and changes in personality (increased instability and irritability, social withdrawal, paranoid traits). In general, however, the symptoms must persist for more than 6 months in order to diagnose a dementia syndrome.
