Alzheimer’s disease is a chronic neurodegenerative disease of aging this disease is a common referred disorder throughout the world. Common to individuals aged 60 years and older, it slowly worsens brain abilities and a person finds it difficult to remember things, think or carry out activities as they used to. In terms of stages the process of Alzheimer’s is divided into seven stages which reflect certain changes of the human brain. This article focuses on the structure of the disease progression across these seven stages of Alzheimer’s as well as the neurological changes.

Stage 1: No Impairment

In the first stage, a person does not have any symptoms of the disease, therefore they do not display any changes in their everyday life. Symptomologically, early signs of Alzheimer’s may not be present at all yet but neurologically, Alzheimer’s may already be germinating. There are progressive alterations in the brain, including amyloid plaques deposition and tau protein tangles, which develop with no or minimal clinical symptoms. Amyloid plaques are conglomerations of protein pieces that prevent the signal from passing between two cells and tau tangles hinder transport of nutrients inside the neurons. At this stage of the infection, such changes are latent and do not cause any symptoms to the infected person.

Stage 2: Very Mild Cognitive Decline

For the first stage, there are no recognisable symptoms of dementia but for Stage 2, the symptoms are insignificant and pass as ageing effects. The individual may have less serious memory loss such as more often than not forgetting the name of a person or even where he or she put an object. At the neurobiological level, plaques and tangles build up, contributing to very mild neuronal connection impairment. Neurons start to degenerate along with placing of support structures, especially in parts of the brain that regulate the processes of memory and learning – the hippocampus. However, these changes still do not indicate unmistakable symptoms of Alzheimer’s disease.

Stage 3: Mild Cognitive Decline

In stage 3, people can also see changes, especially if they are close friends or relatives of the patient and address issue with memory. The person may have problems with speaking, being unable to recall events which took place rather recently, or have problems with planning or executing actions. At this stage, the damage in the hippocampus and the nearby areas come to the fore and they have an impact on everyday functioning. Neuroimaging may begin to show some sign of cerebral shrinkage, particularly the hippocampus as well as the cortex implicated in memory.

Stage 4: Moderate Cognitive Decline (Mild Alzheimer’s Disease)

Alzheimer is usually diagnosed in stage 4; When specific signs are noticed during the physical assessments. An affected person may have poor memory, reduced ability to learn new concepts, or forgetting appointments and handling of everyday matters. Neuropathologically, the extension of staining plaques and tangles becomes more prominent and results in enhanced atrophy in the cerebral cortex that encroaches on cognitive and /or behavioural-emotional front. At this time, the patient may be prescribed medications or advised to change his lifestyle in order to delay the further development of symptoms.

Stage 5: Moderately Severe Cognitive Decline (Moderate Alzheimer’s Disease)

Stage 5 marks a significant decline in cognitive function. The person may require help with everyday activities, such as dressing or grooming. Short-term memory loss is pronounced, with an inability to recall major personal details like their address or phone number. Neurologically, atrophy continues to spread throughout the brain, and the destruction of synaptic connections becomes more widespread, further impairing memory and judgement. As the frontal lobes are increasingly affected, an individual’s behaviour and emotional control may become less stable.

Stage 6: Severe Cognitive Decline (Moderately Severe Alzheimer’s Disease)

In stage 6, the patient is unable to adapt to deadlines and other time frames. People may not be aware of their close relatives and need a lot of assistance in personal care, dressing, feeding, etc. Somatic spry, patient discomfort, confusion, sleeping disturbances, wandering and hallucinations are among the social behavioral changes detected previously at this stage. Neurologically, the brain cortex keeps shrinking, and there is diffuse injury to territories of frontal and temporal lobes, including an area of decision making, speech, and social conduct. Extensive deposits of amyloid plaques and tau tangles together with the loss of neurons greatly diminish the possibility for the patient’s effective relationship with the environment.

Stage 7: Very Severe Cognitive Decline (Late-Stage Alzheimer’s Disease)

The seventh stage of Alzheimer’s disease involves marked deterioration of motor and cognitive function, inability to communicate, and respond to stimuli. The atrophy is more demonstrated at the brain level, and virtually all areas of the brain are affected most. He or she can become bed-ridden, immobile, and may no longer be able to sit, walk or even swallow on his or her own accord. In this stage, the neurons that respire or swallow are impaired in human beings and other mammals. The human body closes down as the head can no longer support critical physical operations of life.

Neurological Changes: The Role of Plaques, Tangles, and Brain Atrophy

Understanding the progression of Alzheimer’s requires recognizing the roles of amyloid plaques, tau tangles, and brain atrophy.

• Amyloid Plaques: These sticky deposits form outside neurons, disrupting communication between brain cells. As they accumulate, they activate immune responses, leading to inflammation that further damages healthy neurons.
• Tau Tangles: Tau is a protein that stabilises microtubules within neurons, but in Alzheimer’s, tau proteins become abnormally twisted, forming tangles. These tangles cause the collapse of the cell’s internal transport system, eventually leading to cell death.
• Brain Atrophy: Throughout Alzheimer’s progression, the brain undergoes substantial atrophy. Areas related to memory, cognition, and emotion are most affected, leading to a significant reduction in brain volume. This shrinkage is visible in brain scans and corresponds with the decline in cognitive and physical abilities.

The Importance of Early Intervention

It might take long years, sometimes, 10 years and over, moving from stage 1 to stage 7. Alzheimer’s disease is highly dependent on early intervention. Such signs, if identified early enable practitioners to seek medical intervention and develop methods to put a brake on the progression. Antipsychotics, antidepressants, antianxiety, and anti-psychotic medications, alongside changes in such factors as exercise and mental stimulation, make it possible to prolong the affected person’s quality of life.

Conclusion

Alzheimer’s disease is subdivided into seven stages mainly due to the progressive healthcare of neurodegeneration that affects the patient’s cognitive, physical and emotional functioning. It starts with subclinical alterations in the brain and progresses to alter all aspects of an individual’s life. Comforting and supporting patients’ main features involve identifying the stages of the illness in order to minimize obstacles and render maximum assistance. Alzheimer’s seems to be characterized by progressive losses but is also about the ability to give care and facilitate relationships. Caring for the patients themselves or contributing to the advancement of our knowledge about this disease is essential to helping patients with Alzheimer’s and their families.