According to the Alzheimer’s Society, there are around 800,000 people in the U.K. with dementia at the present time. 1 in 3 people over the age of 65 will develop it and 2/3 of those diagnosed are women. The number of people living with dementia is increasing as we live longer, with a projected figure of around 1,000,000 by 2021.

Dementia is a term used to describe symptoms that may include memory loss, difficulties with problem-solving, numbers and language. Dementia is a result of the brain being damaged by a series of strokes or diseases such as Alzheimer’s.

10 types of dementia

Alzheimer’s – The most common type of dementia, accounting for 60%-80% of cases. Symptoms in the early stages include lapses in memory and problems finding the right words. As Alzheimer’s progresses, people become confused, frequently forgetting the names of others, appointments, places and recent events. They may also experience mood swings, become withdrawn and have difficulty carrying out everyday activities.

Vascular dementia – Accounts for around 10% of dementia cases. Previously known as multi-infarct or post-stroke dementia as it is caused by problems with the flow of blood to the brain. Symptoms can be similar to those found in Alzheimer’s, although people may particularly experience problems with speed thinking, concentration, communication, and memory. Depression and anxiety may accompany the dementia, there may be symptoms of a stroke or seizures. Other symptoms may include visual mistakes, changes in behaviour, difficulties in walking, hallucinations, problems with continence and psychological symptoms such as obsessiveness.

Dementia with Lewy bodies (DLB) – People diagnosed with Lewy bodies will have memory loss and thinking problems also associated with Alzheimer’s, but they are also more likely to have initial or early symptoms such as sleep disturbances, well-formed visual hallucinations, and muscle rigidity or other parkinsonian movement features. Symptoms will vary from person to person, but they will usually have some of the symptoms of Alzheimer’s, some parkinsonian symptoms and some unique to DLB. Problems with attention and alertness are common, along with difficulties in judging distances and perceiving objects in 3D. Visual hallucinations occur in most people, with some but not all also experiencing auditory hallucinations. Up to 2/3 of people have movement problems and sleep disorders are common.

Mixed dementia – This dementia is more common than previously thought and happens when abnormalities linked to more than one type of dementia occur in the brain at the same time. Symptoms vary depending on the types of brain changes or the part of the brain involved. In some cases, symptoms can be indistinguishable from those occurring in Alzheimer’s or other types of dementia.

Fronto temporal dementia – Includes dementias such as behavioural variant FTD (bvFTD), primary progressive aphasia, Pick’s disease and progressive supranuclear palsy. Symptoms include changes in personality and behaviour and difficulty with language.

Parkinson’s disease – As Parkinson’s is a progressive disease, it usually results in an advanced form of dementia similar to Alzheimer’s or Lewy bodies. Symptoms include problems with movement which becomes rigid and slow. As the disease progresses, symptoms may become similar to a person with Lewy bodies or Alzheimer’s.

Creutzfeldt-Jakob diseaseCJD is the most common human form of a group of rare, fatal brain disorders affecting people and certain other mammals. A rapidly fatal disorder that impairs memory and coordination and causes behaviour changes.

Normal pressure hydrocephalus – Symptoms include memory loss, difficulty with walking and the inability to control urination.

Huntington’s diseaseA progressive brain disease that caused by a defective gene on chromosome 4. Symptoms include abnormal involuntary movements, a severe decline in thinking and reasoning skills, and irritability, depression and other mood changes.

Wernicke-Korsakoff SyndromeA chronic memory disorder mostly as a result of alcohol misuse. It results in a severe deficiency of thiamine – vitamin B1. Symptoms include memory problems that may be strikingly severe while other thinking and social skills seem relatively unaffected.