Disease of the month: Alzheimer’s disease

There is no cure, Alzheimer’s is a devastating disease for both those who suffer from, and those who care for someone with the disease, Fergus Bescoby discusses the implications for those affected

There will be few people who are unaware of this disease in one way or another, be it with a suffering family member or friend, or watching film or drama on television. It is a cruel disease for all concerned, not least the family members and friends who offer care, support and love for the victim.

Alzheimer’s disease is the most common cause of dementia, affecting around 570,000 people in the UK. The term ‘dementia’ describes a set of symptoms which can include loss of memory, mood changes, and problems with communication and reasoning. These symptoms occur when the brain is damaged by certain diseases and conditions, including Alzheimer’s disease.

Alzheimer’s disease is a physical disease affecting the brain and was first described by the German neurologist Alois Alzheimer. During the course of the disease, protein ‘plaques’ and ‘tangles’ develop in the structure of the brain, leading to the death of brain cells. People with Alzheimer’s also have a shortage of some important chemicals in their brain. These chemicals are involved with the transmission of messages within the brain.

Alzheimer’s is a progressive disease, which means that gradually, over time, more parts of the brain are damaged. As this happens, the symptoms become more severe.

People with Alzheimer’s may have trouble remembering things that happened recently or names of people they know. People may not recognise family members or have trouble speaking, reading or writing. They may forget how to brush their teeth or comb their hair.

People in the early stages of Alzheimer’s disease may experience lapses of memory and have problems finding the right words. As the disease progresses, they may:

■ Become confused and frequently forget the names of people, places, appointments and recent events

■ Experience mood swings, feel sad or angry, or scared and frustrated by their increasing memory loss

■ Become more withdrawn, due either to a loss of confidence or to communication problems

■ Have difficulty carrying out everyday activities – they may get muddled checking their change at the shops or become unsure how to work the TV remote.

Later on, they may become anxious or aggressive, or wander away from home. Eventually, they need total care. This can cause great stress for family members who must care for them.

While there are some common symptoms of Alzheimer’s disease, it is important to remember that everyone is unique. No two people are likely to experience Alzheimer’s disease in the same way.

Mild cognitive impairment

Recently, some doctors have begun to use the term mild cognitive impairment (MCI) when an individual has difficulty remembering things or thinking clearly but the symptoms are not severe enough to warrant a diagnosis of Alzheimer’s disease.

Recent research has shown that people with MCI have an increased risk of developing Alzheimer’s disease. However, the conversion rate from MCI to Alzheimer’s is low (about 10% t0 20% each year), and consequently a diagnosis of MCI does not always mean the person will go on to develop Alzheimer’s.

What causes Alzheimer’s disease?

So far, no one single factor has been identified as a cause for Alzheimer’s disease. It is likely that a combination of factors, including age, genetic inheritance, environmental factors, lifestyle and overall general health, are responsible. In some people, the disease may develop silently for many years before symptoms appear.

Age

Alzheimer’s disease is most common in people over 65 years of age, and affects slightly more women than men.

The Alzheimer’s Society estimates that, in people over 65 years of age, 1 in 14 is affected by Alzheimer’s disease. The risk increases with age, and people who are over 80 years of age are thought to have a one in six chance of developing the condition.

Dementia in people under 65 years of age, known as early-onset dementia, is less common. In the UK, around 2% of all dementia cases are early-onset dementia.
Genetic inheritance

Many people fear that they may inherit Alzheimer’s disease and scientists are currently investigating the genetic background to this disease.

Relatives have a higher risk than the general population for developing the disease. In fact, people with at least one first-degree relative (parent or sibling) with Alzheimer’s disease are 3.5 times as likely to develop the disease. This risk increases for each additional relative with Alzheimer’s disease.

This strong tendency of Alzheimer’s disease to run in families is due, in part, to mutations in certain genes. Scientists have found several genes that are involved in early onset Alzheimer’s disease, but so far they do not know the gene responsible for inherited late-onset Alzheimer’s disease.