Abstract

Dementia is a set of symptoms characterized by deterioration of memory and cognitive functions. Dementia diseases include Alzheimer's disease, Lewy body dementia, frontotemporal dementia, vascular dementia, and mixed dementia. This disease represents an escalating social issue, particularly in a society with an increasing elderly population. In 2019, 271,998 people succumbed to dementia, making Alzheimer's disease the sixth most prevalent cause of death. The pathophysiology of Alzheimer's disease is complex and not fully understood. It is a multifaceted disease, with its pathogenesis influenced by a combination of genetic, environmental, and lifestyle factors. One of the genes involved in the pathogenesis of the disease is the apolipoprotein E (APOE) gene, which is one of the most common risk factors for Alzheimer's disease. The significance of other genes, including presenilin genes (PSEN1 and PSEN2), the TREM2 gene, the MAPT gene, and the APP gene, linked to various forms of dementia, is also emphasized. Another issue is the growing number of identified genetic variants within genes implicated in the onset of dementia. Dementia diseases are also characterized by chemical alterations in the brain, including the accumulation of abnormal excitotoxic proteins, varying degrees of inflammation, and metabolic disorders. This article aims to summarize current discoveries in the field of dementia and highlight the significance of molecular factors in its pathogenesis. Gaining insight into the pathogenic mechanisms of dementia may allow for faster diagnosis of the disease and facilitate the creation of more efficient patient care plans.