Full list of dementia symptoms — six little-known types explained

The word « dementia » describes a group of symptoms caused by different diseases or illnesses that damage the brain. Around one million people are thought to be living with dementia in the UK and the most people have heard of common types such as Alzheimer’s disease, vascular dementia or dementia with Lewy bodies.

But there are more than 100 forms caused by diseases that affect the brain in different ways. Around one in 20 people diagnosed in the UK have one of these rarer forms, according to Alzheimer’s Society. Symptoms can vary depending on the cause, particularly in the early stages. Here are six lesser-known types of dementia and their symptoms.

1. Creutzfeldt–Jakob disease (CJD)

CJD is caused by an abnormally shaped protein called a prion infecting the brain. These prions accumulate and cause irreversible damage to nerve cells.

One type, variant CJD, is thought to be caused by consuming meat from a cow with bovine spongiform encephalopathy. This human form of mad cow disease caused a huge scare in the UK during the late 1990s and early 2000s.

Symptoms of CJD can progress rapidly, with many sufferers dying within a year.

The signs include: loss of intellect and memory, changes in personality, loss of balance and co-ordination, slurred speech, vision problems and blindness, abnormal jerking movements and progressive loss of brain function and mobility.

2. Huntington’s disease

Huntington’s is an inherited genetic condition that affects movement, thinking and mood. It cannot currently be cured. Symptoms usually start between the ages of 30 and 50, but can occur at any age.

Early signs include: low mood, depression and anxiety, irritability and obsessive–compulsive behaviours, memory problems, personality changes, small twitching or jerking movements and becoming clumsy.

More advanced symptoms include: difficulty swallowing and speaking, weight loss, muscles becoming stiff and movement slower, more severe mood or personality changes.

Normal pressure hydrocephalus (NPH)

NPH occurs when too much fluid builds up in a person’s brain despite normalised pressure readings. It most commonly affects people over the age of 60 and symptoms can progress quickly.

The cause is often unknown but NPH sometimes develops after a head injury, brain bleed or severe meningitis.

Symptoms include: difficulty focusing or organising, planning and switching between tasks, memory problems, increased confusion and difficulty responding to questions, loss of bladder control and difficulty with walking such as shuffling.

Progressive supranuclear palsy (PSP)

PSP is caused by increasing numbers of brain cells becoming damaged over time by the build-up of a protein called tau. It mostly affects people over the age of 60.

The word « supranuclear » refers to the parts of the brain just above the nerve cells that control eye movement.

Symptoms include: problems with balance and mobility (including frequent falls), changes in behaviour such as irritability or apathy, muscle stiffness, an inability to control eye and eyelid movement, quiet or slurred speech, difficulty swallowing, slowness of thought and memory problems.

CADASIL

CADASIL stands for Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy.

It is a rare, inherited condition caused by a gene mutation. A person who carries the faulty gene has a 50/50 chance of developing CADASIL.

Sufferers are likely to experience a series of mild strokes which a damage their brain tissue, sometimes accompanied by migraines.

Common symptoms include: migraines with aura, slurred speech, weakness down one side of the body and difficulty with paying attention, planning, organising, reasoning or problem-solving.

Atypical Alzheimer’s disease

There are two forms of atypical Alzheimer’s disease — frontal variant Alzheimer’s disease (fvAD) and posterior cortical atrophy (PCA).

Around one in 50 people with Alzheimer’s have fvAD, where the condition affects the frontal lobes of their brain earlier than usual.

Damage to the frontal lobes can cause symptoms including: problems with planning and decision-making, and behavioural changes.

Behavioural changes can include loss of inhibitions and behaving inappropriately, loss of motivation, not understanding or caring about the feelings of others, repetitive behaviour and unusual food cravings.

PCA occurs when the back of the brain is most affected — a region called the visual cortex. Early symptoms include: difficulty recognising faces and objects in pictures, difficulty judging distances and problems with spatial awareness.

• You can find out more about rarer types of dementia here.