Alzheimer's disease is a progressive and neurodegenerative disorder that primarily affects the brain's cognitive functions. It is the most common cause of dementia, responsible for approximately 60-80% of all dementia cases. The disease typically starts with subtle memory loss and difficulty in recalling recent events, which may be mistaken for normal aging initially. However, as Alzheimer's progresses, it impairs other cognitive abilities, including language, problem-solving, decision-making, and spatial awareness.
The hallmark features of Alzheimer's disease are the presence of abnormal protein deposits in the brain. Amyloid plaques and tau tangles accumulate between nerve cells, leading to the dysfunction and perishing of brain cells. These changes primarily affect the hippocampus, a brain region essential for memory formation, learning, and emotional regulation. As the disease advances, the damage spreads to other areas of the brain, resulting in widespread loss of brain cells and significant brain shrinkage.
The progression of Alzheimer's disease can be broadly categorized into three stages: early/mild, middle/moderate, and late/severe stages. In the early stage, individuals may experience mild memory loss and subtle cognitive difficulties. As the disease advances, memory problems become more apparent, and individuals may struggle with language, orientation, and daily tasks. In the late stage, severe cognitive decline leads to a loss of ability to communicate, recognize loved ones, and perform basic self-care activities.
