20 August 2020 Author : Sofia Nunes Oliveira What is dementia? Dementia means a global loss of cognitive functions that is severe enough to interfere with patients life activities. Dementia can be caused by several diseases , including Alzheimer disease and other degenerative diseases, but also by stroke, tumors, metabolic and infectious diseases. What are cognitive functions? Cognitive functions are the functions of the brain that allow us to acquire knowledge . They are, among others, the functions of: Language; Calculation; Memory; Visuospatial capacity; Reasoning; Planning ability. What is Alzheimer disease? Alzheimer disease is a degenerative brain disease, of unknown cause, in which the accumulation in the brain neurons of toxic substances - amyloid substance - leads to its progressive death. This disease is the most frequent cause of dementia in Portugal . It is responsible for about 70% of the 200,000 cases of dementia estimated in Portugal by the OECD. The main risk factor for Alzheimer disease is age, being very frequent above 75 years of age. The first symptoms are usually memory problems such as: Small forgetfulness; Difficulty in fixing new facts; Ask repetitive questions; Make mistakes with dates. Subsequently, the disease affects other cognitive functions such as language, with loss of vocabulary, and executive functions. The patient loses initiative and planning capacity and may stop doing his daily activities and main occupations. As the disease progresses it can affect all brain functions, including gait and ability to recognize other people. What other diseases can cause dementia? Many other diseases that affect the functioning of the brain can cause dementia. The most frequent degenerative diseases are Alzheimer disease, Lewy body disease, Parkinson disease and frontotemporal degeneration. However, successive strokes or in strategic locations of the brain also cause dementia and are a very important and frequent cause of dementia in Portugal. Other diseases such as metabolic diseases (thyroid disease, vitamin deficits), infectious diseases, problems with cerebrospinal fluid circulation, tumors, sleeping disorders, severe epilepsies, mood disorders (for example, depression major), among others, can also cause dementia, especially if they are not properly diagnosed and treated . The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
