Recognizing the First Signs: Why Early Detection of Alzheimer’s Matters

By - Dr. B K Madhusudhan, Lead Consultant – Neurology, Aster RV Hospital

Alzheimer's is a brain disease which is characterised by decline in memory, thinking and reasoning skills. Alzheimer's is not a normal part of aging and it worsens over time. Alzheimer's is a progressive disease, where dementia symptoms slowly worsen over years.

It accounts for 60-80% of dementia cases, making it the most likely cause of dementia. It typically affects aged persons, with the risk dramatically rising beyond 65 years

Alzheimer's disease is caused by the abnormal build-up of proteins in and around brain cells. One of the proteins involved is called amyloid, deposits of which form plaques around brain cells. The other protein is called tau, deposits of which form tangles within brain cells.

Although it's not known exactly what causes this process to begin, scientists now know that it begins many years before symptoms appear. As brain cells become affected, leading to decrease in chemical messengers which are called neurotransmitters involved in sending messages, or signals, between brain cells.

The Levels of acetylcholine neurotransmitter are particularly low in the brains of people with Alzheimer's disease. Over time, different areas of the brain shrink. The areas of brain that are initially affected are responsible for memories. In more unusual forms of Alzheimer's disease, different areas of the brain are affected.

Initial changes

• Microscopic changes in the brain begin long before the first signs of memory loss.
• The brain has 100 billion nerve cells called neurons. Each nerve cell connects with many others to form communication networks.
• To the functioning of theses neurons, brain cells operate like tiny factories. They receive supplies, generate energy, construct equipment and get rid of waste. Cells also process and store information and communicate with other cells. Keeping everything running requires coordination as well as large amounts of fuel and oxygen.
• Alzheimer's disease prevents parts of a cell's factory from running well. They are not sure where the trouble starts. But just like a real factory, backups and breakdowns in one system cause problems in other areas. As damage spreads, cells lose their ability to do their jobs and, eventually die, causing irreversible changes in the brain.

Stages of Alzheimer’s disease

In the early stages, the main symptom of Alzheimer's disease is memory lapses. forget about recent conversations or events, misplace items, forget the names of places and objects, have trouble thinking of the right word, ask questions repetitively, show poor judgement or find it harder to make decisions, become less flexible and more hesitant to try new things and there are often signs of mood changes, such as increasing anxiety or agitation, or periods of confusion.

As Alzheimer's disease develops, in the middle stage, memory problems will get worse. Someone with the condition may find it increasingly difficult to remember the names of people they know and may struggle to recognise their family and friends. State of confusion and disorientation like getting lost, obsessive, repetitive or impulsive behaviour, delusions, disturbed sleep, changes in mood, such as frequent mood swings, depression and feeling increasingly anxious, frustrated or agitated, difficulty performing spatial tasks, such as judging distances.

In the later stages of Alzheimer's disease, the symptoms reach extreme level and can be upsetting for the person with the condition, for their family and care givers. Hallucinations and delusions get worse as and when the condition progresses.

Diagnosing

• Techniques for imaging the brain help with the detection of Alzheimer’s, where they identify important disease-related biomarkers by offering insightful information on the structural and functional alterations happening in the brain.
• PET scans help to visualise and also measure the beta-amyloid plaques in the brain which assists the identification and differential diagnosis of the disease.
• Single-photon emission computed tomography (SPECT) imaging can reveal essential details regarding regional brain function and illustrate regions with decreased blood flow or aberrant metabolism.
• An earlier diagnosis will allow the patient to be open about their problems with family and their support network in each stage of the disease, which would help in giving the patient a peace of mind.
• It also helps families plan for the future. They can take care of financial and legal matters, address potential safety issues, learn about living arrangements, and develop support networks